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Sample records for milk renneting properties

  1. Ultrasound improves the renneting properties of milk.

    Science.gov (United States)

    Liu, Zheng; Juliano, Pablo; Williams, Roderick P W; Niere, Julie; Augustin, Mary Ann

    2014-11-01

    The effects of ultrasound application on skim milk (10% w/w total solids at natural pH 6.7 or alkali-adjusted to pH 8.0) prior to the renneting of milk at pH 6.7 were examined. Skim milk, made by reconstituting skim milk powder, was sonicated at 20kHz and 30°C (dissipated power density 286kJkg(-1)) in an ultrasonic reactor. The rennet gelation time, curd firming rate, curd firmness, and the connectivity of the rennet gel network were improved significantly in rennet gels made from milk ultrasonicated at pH 8.0 and re-adjusted back to pH 6.7 compared to those made from milk sonicated at pH 6.7. These renneting properties were also improved in milk sonicated at pH 6.7 compared to those of the non-sonicated control milk. The improvements in renneting behavior were related to ultrasound-induced changes to the proteins in the milk. This study showed that ultrasonication has potential to be used as an intervention to manipulate the renneting properties of milk for more efficient manufacturing of cheese.

  2. Rheological properties of rennet-induced skim milk gels.

    NARCIS (Netherlands)

    Zoon, P.

    1988-01-01

    The rheological properties of rennet-induced skim milk gels, which are viscoelastic materials, were studied under various conditions.Dynamic and stress relaxation experiments were performed at small deformations of the gel network, whereas constant stress (creep) experiments were performed at large

  3. Rheological and structural properties of differently acidified and renneted milk gels.

    Science.gov (United States)

    Liu, X T; Zhang, H; Wang, F; Luo, J; Guo, H Y; Ren, F Z

    2014-01-01

    In this study we assessed the rheological and structural properties of differently acidified and renneted milk gels by controlling pH value and renneting extent. Skim milk were exactly renneted to 4 extents (20, 35, 55, and 74%) and then direct acidified to the desired pH (4.8, 5.0, 5.2, 5.5, 5.8, and 6.2), respectively. Rheological properties were assessed by dynamic rheological measurements, structural properties were studied by spontaneous whey separation and confocal laser scanning micrograph, and protein interactions were studied by dissociation test. Results showed that minimally renneted milk samples (20 and 35%) formed weak gels with low storage modulus, and the acidification range within which gels could form was narrow (pH ≤ 5.2). Highly renneted milk samples formed more gels with high storage modulus. The results of this study revealed that acidification determined the structural properties of highly renneted milk gels. As pH increased from 5.0 to 6.2, highly renneted milk gels had lower loss tangent, decreased spontaneous syneresis, and smaller pores. For both the low and high rennetings, divalent calcium bonds contributed less at low pH than at high pH. In conclusion, renneting increased the pH range suitable for gel formation; acidification determined the spontaneous syneresis and microstructure of highly renneted milk gels.

  4. Rennet coagulation of heated milk concentrates

    OpenAIRE

    Schreiber, Regina; Hinrichs, Jörg

    2000-01-01

    International audience; The high temperature heating of cheese milk is a useful tool for preventing late fermentation during cheese ripening if the renneting properties remain unchanged. The aim of the investigations was to find heating conditions which guarantee the inactivation of clostridia spores but still enable rennet coagulation of the heated milk and milk concentrates respectively. The gel strength of the rennet gels increased the more the casein content increased. The native whey pro...

  5. Effect of high-pressure homogenisation on rheological properties of rennet-induced skim milk and standardised milk gels.

    Science.gov (United States)

    Lodaite, Kristina; Chevalier, François; Armaforte, Emanuele; Kelly, Alan L

    2009-08-01

    The effects of high-pressure homogenisation (HPH) in the pressure range 100-300 MPa on the gel formation and rheological properties of rennet-induced skim milk (0.08%, fat, w/w) and standardised milk (3.60% fat, w/w) gels at pH 6.60 were studied. The average casein micelle size in skim milk was significantly reduced and the gel formation time decreased when skim milk was subjected to the pressures of 200 and 300 MPa. The storage modulus of rennet-induced skim milk gels at 2700 s after rennet addition was higher for samples homogenised at higher pressures, which contained smaller casein particles. HPH had little effect on the large deformation properties of rennet-induced skim milk gels. The gel formation time of renneted standardised milk was significantly reduced as a result of HPH, while the storage modulus of rennet-induced milk gels 2700 s after rennet addition increased with increasing homogenising pressure. The apparent fracture stress was slightly higher for standardised milk gels formed from HPH-treated milk, whereas the apparent strain at fracture was lower, than that of unhomogenised milk. In conclusion, HPH treatment influenced gel formation processes of skim milk and its small-deformation rheological properties, mainly through modification of casein micelles. HPH also significantly affected the gel formation process of standardised milk gels and its rheological properties as a result of an increase in volume fraction of aggregating particles, while the particle size was of lesser importance.

  6. Rennet Coagulation and Cheesemaking Properties of Thermally Processed Milk: Overview and Recent Developments.

    Science.gov (United States)

    Kethireddipalli, Prashanti; Hill, Arthur R

    2015-11-04

    Thermally induced changes in milk proteins and minerals, particularly interactions among caseins and denatured whey proteins, influence important properties of dairy products in both positive and negative ways. Whereas the extensive protein connectivity and increased water-holding capacity resulting from such heat-induced protein modification account for the much desired firmness of acid gels of yogurt, thermal processing, on the other hand, severely impairs clotting and adversely affects the cheesemaking properties of rennet-coagulated cheeses. In technological terms, the principal ongoing challenge in the cheese industry is to take advantage of the water-holding capacity of thermally aggregated whey proteins without compromising the rennetability of cheese milk or the textural and functional attributes of cheese. Including some recent data from the authors' laboratory, this paper will discuss important aspects and current literature on the use of thermally processed milk in the production of rennet-coagulated cheeses and also some of the potential alternatives available for inclusion of whey proteins in cheese, such as the addition of microparticulated whey proteins to cheese milk.

  7. Effect of Milk Fat Substitution of Rennet Milk Induced Coagulation on Physico-Chemical Properties

    Directory of Open Access Journals (Sweden)

    Imène Felfoul

    2013-01-01

    Full Text Available The objective of this paper was to study the effect of milk fat substitution by (W1/O/W2 multiple emulsions based on olive oil in comparison with full and low-fat milks on milk behavior during rennet coagulation. Therefore, based on the turbidimetric and conductivimetric methods, a follow up of enzymatic coagulation is realized. Drainage of renneted gels was followed by syneresis study and cheese yield. The comparison between the coagulation aptitude of low fat milk and milk-olive oil emulsion showed that the hydrolysis phase extended up to 35 minutes for full fat milk and up to 38 minutes for milk-olive oil emulsion. The transition phase solid/gel was shorter in the case of the whole milk. The reticulation phase was shorter in the case of milk-olive oil emulsion. The milk conductivity depended on the milk richness in fat content. Milk-olive oil emulsion showed the lowest cheese-making yield compared to its full and low-fat counterpart.

  8. A comparison of the determination of the rennet coagulation properties of bovine milk

    Directory of Open Access Journals (Sweden)

    Roman Pytel

    2016-07-01

    Full Text Available The aim of the work was compared of two different methods (the visual method and the nephelo turbidimetry method for determination of rennet coagulation time. It was observed the effect of heat treatment of milk; types of rennet and addition of different amount of CaCl2 into the pasteurized milk. It was used two different chymosin rennet. For the visual method was milk sample (100 mL equilibrated at 35 °C, 1 mL of rennet was added into milk and was measured the time required for the first visible flakes (visual method. For the determination rennet coagulation time by nephelo-turbidimetry was removed part of milk with rennet and placed into nephelo-turbidimetry. Milk had a titratable acidity in the range from 6.5 to 7.0 °SH, average pH of milk was 6.68. Dry matter content was in range from 12.351 to 13.142%. The average content of protein by Kjeldahl was 3.14%, fat by Gerber 4.34%, lactose by polarimetry 4.68% and calcium content 1.1%. The pasteurized milk had the worst rennet coagulation time about 32 s compared to the raw milk. The difference coagulation time between milk with addition of 20 µL CaCl2 and 40 µL CaCl2 was in range 21 s to 26 s by visual method. The difference coagulation time between milk with addition of 20 µL CaCl2 and 40 µL CaCl2 was 15 s by nephelo-turbidimetry method. There occurred statistically non-significant differences in most of the measurements, comparing the visual and the nephelo-turbidimetric method. The heat treatment, addition of CaCl2 and using of different rennet had an influence on the curd category. It was obtained, that using nephelo-turbidimetry shown objective results for measuring the rennet coagulation time contrary the subjective visual method. Further, the results obtained by nephelo-turbidimetry are accurate and determined with the lower variation.

  9. Genetic parameters for rennet- and acid-induced coagulation properties in milk from Swedish Red dairy cows.

    Science.gov (United States)

    Gustavsson, F; Glantz, M; Poulsen, N A; Wadsö, L; Stålhammar, H; Andrén, A; Lindmark Månsson, H; Larsen, L B; Paulsson, M; Fikse, W F

    2014-01-01

    Milk coagulation is an important processing trait, being the basis for production of both cheese and fermented products. There is interest in including technological properties of these products in the breeding goal for dairy cattle. The aim of the present study was therefore to estimate genetic parameters for milk coagulation properties, including both rennet- and acid-induced coagulation, in Swedish Red dairy cattle using genomic relationships. Morning milk samples and blood samples were collected from 395 Swedish Red cows that were selected to be as genetically unrelated as possible. Using a rheometer, milk samples were analyzed for rennet- and acid-induced coagulation properties, including gel strength (G'), coagulation time, and yield stress (YS). In addition to the technological traits, milk composition was analyzed. A binary trait was created to reflect that milk samples that had not coagulated 40min after rennet addition were considered noncoagulating milk. The cows were genotyped by using the Illumina BovineHD BeadChip (Illumina Inc., San Diego, CA). Almost 600,000 markers remained after quality control and were used to construct a matrix of genomic relationships among the cows. Multivariate models including fixed effects of herd, lactation stage, and parity were fitted using the ASReml software to obtain estimates of heritabilities and genetic and phenotypic correlations. Heritability estimates (h(2)) for G' and YS in rennet and acid gels were found to be high (h(2)=0.38-0.62) and the genetic correlations between rennet-induced and acid-induced coagulation properties were weak but favorable, with the exception of YSrennet with G'acid and YSacid, both of which were strong. The high heritability (h(2)=0.45) for milk coagulating ability expressed as a binary trait suggests that noncoagulation could be eliminated through breeding. Additionally, the results indicated that the current breeding objective could increase the frequency of noncoagulating milk and

  10. Influence of colloidal calcium phosphate level on the microstructure and rheological properties of rennet-induced skim milk gels

    DEFF Research Database (Denmark)

    Koutina, Glykeria; Knudsen, Jes Christian; Andersen, Ulf

    2015-01-01

    lactose, to obtain varying levels of micellar calcium and phosphorus but constant value of pH, serum and free calcium, and serum phosphorus. Bovine chymosin was added to the skim milk samples after dialysis and microstructural and rheological properties during gel formation were recorded at 30°C. Samples...... of rennet gel formation. The protein network of rennet gels after dialysis was more compact with many aggregates as demineralization decreased. The small protein particles are able to increase the potential connection points among proteins, support particle fusion and cause a compact structure....... after dialysis needed approximately 30min after the addition of chymosin to form rennet gels. In addition, low micellar calcium and phosphorus values were both found to correlate with slightly less time for the gels to be formed. This information highlights the importance of CCP in the primary phase...

  11. Effect of the levels of N fertilizer, grass and supplementary feeds on nitrogen composition and renneting properties of milk from cows at pasture.

    Science.gov (United States)

    Hermansen, J E; Ostersen, S; Aaes, O

    1994-05-01

    In a 2 x 2 x 3 factorial design grazing experiment we investigated the effect of fertilizer (none or 240 kg N/ha), amounts of clover grass available (low or high) and type and level of daily supplementary feed for each cow (3.5 kg barley, 3.5 kg concentrate mixture rich in protein and fat, or both, 7 kg) on the protein composition and renneting properties of their milk. The experiment was carried out in two successive grazing seasons (years) and included a total of 79 Danish Holstein cows. The effect on milk protein composition was determined in both years whereas the effect on renneting properties was determined only in the second year. Fertilization of the clover grass significantly decreased total milk protein concentration (-1.4 g/kg; P whey protein N. Fertilization had no effect on renneting properties. Increased availability of clover grass significantly increased milk protein concentration (1 g/kg; P < 0.05) and resulted in significantly poorer renneting properties, that is increased clotting time (P < 0.01) and decreased coagulum development. These effects seemed to be mediated through an effect on the pH of the milk (+0.05; P < 0.05) as the effect was markedly reduced when statistical correction was made for the actual pH. Use of the protein- and fat-rich concentrate mix (3.5 kg) significantly reduced the total protein content of the milk (P < 0.05) and increased the proportion of non-protein N (NPN) in total N compared with use of the other supplementary feeds (P < 0.05). We found no effect on renneting properties of the different supplementary feeds. Throughout the grazing season and independent of the main treatments, the NPN proportion of milk N increased at the expense of casein N. At the same time, renneting properties became poorer, especially with high clover grass availability.

  12. Effects of composite casein and beta-lactoglobulin genotypes on renneting properties and composition of bovine milk by assuming an animal model

    Directory of Open Access Journals (Sweden)

    T. IKONEN

    2008-12-01

    Full Text Available The effects of kappa-beta-casein genotypes and b-lactoglobulin genotypes on the renneting properties and composition of milk were estimated for 174 and 155 milk samples of 59 Finnish Ayrshire and 55 Finnish Friesian cows, respectively. As well as the random additive genetic and permanent environmental effects of a cow, the model included the fixed effects for parity, lactation stage, season, kappa-beta-casein genotypes and b-lactoglobulin genotypes. Favourable renneting properties were associated with kappa-beta-casein genotypes ABA 1 A 2 , ABA 1 A 1 and AAA 1 A 2 in the Finnish Ayrshire, and with ABA 2 B, AAA 1 A 3 , AAA 2 A 3 , ABA 1 A 2 and ABA 2 A 2 in the Finnish Friesian. The favourable effect of these genotypes on curd firming time and on firmness of the curd was partly due to their association with a high kappa-casein concentration in the milk. The effect of the kappa-casein E allele on renneting properties was unfavourable compared with that of the kappa-casein B allele, and possibly with that of the A allele. The beta-lactoglobulin genotypes had no effect on renneting properties but they had a clear effect on the protein composition of milk. The beta-lactoglobulin AA genotype was associated with a high whey protein % and beta-lactoglobulin concentration and the BB genotype with a high casein % and casein number.;

  13. Influence of fat replacement by inulin on rheological properties, kinetics of rennet milk coagulation, and syneresis of milk gels.

    Science.gov (United States)

    Arango, O; Trujillo, A J; Castillo, M

    2013-04-01

    The objective of this study was to evaluate the effect of inulin as a fat replacer on the rheological properties, coagulation kinetics, and syneresis of milk gels. A randomized factorial design, replicated 3 times, with 3 inulin concentrations (0, 3, and 6%), 2 levels of fat (gels. The observed effect, which was more evident on the aggregation reaction, depended on the concentration of inulin and the coagulation temperature. Addition of 6% inulin reduced the clotting time by approximately 26% and the time at which the gel reached a storage modulus equal to 30 Pa by approximately 36%. The optical parameter R'max, defined as the maximum value of change in light backscatter profile/change in time (where R' = dR/dt), was used to calculate an approximation of the temperature coefficients (Q10) for milk coagulation. Increasing fat concentration induced a consistent increase in all the optical, rheological, and visual parameters studied, although the observed trend was not statistically significant. The addition of inulin at a level of 6% produced a reduction in syneresis and increased the curd yield by approximately 30%. It was concluded that the addition of inulin affects the kinetics of milk coagulation and the cutting time and, therefore, the use of inline sensors such as near-infrared spectrometry may be necessary for optimal process control.

  14. The renneting of milk : a kinetic study of the enzymic and aggregation reactions

    NARCIS (Netherlands)

    Hooydonk, van A.C.M.

    1987-01-01

    The rennet-induced clotting of milk was studied under various conditions. The kinetics of the enzymic and aggregation reactions was analysed separately and, where possible, related to the physico-chemical properties of the casein micelle and its environment.

    The effects of important

  15. Effects of dietary protein supply on caseins, whey proteins, proteolysis and renneting properties in milk from cows grazing clover or N fertilized grass.

    Science.gov (United States)

    Hermansen, J E; Ostersen, S; Justesen, N C; Aaes, O

    1999-05-01

    The objective of this work was to examine whether variation in the amino acid supply to cows could be a reason for the reduced casein content and poorer renneting properties of milk that often occur in late summer, or whether these effects are related to proteolysis in the raw milk. In a 2 x 2 x 2 factorial design, we investigated the effects of sward (clover v. rye-grass) and supplementary feed with a high or low level of rumen-soluble N or of rumen undegradable protein on milk protein composition during the grazing season. A total of 32 Danish Holstein cows were included in the experiment. Milk protein and casein contents and the ratios casein N:total N and casein:true protein were at a minimum in late summer, whereas the contents of urea, non-protein N and whey protein were higher during this period. These seasonal effects were unrelated to either the type of supplementary feed or the type of sward; neither were they clearly related to proteolysis, although casein: true protein was related to the proteose peptone content. The results indicated that whey proteins other than alpha-lactalbumin or beta-lactoglobulin accounted for the higher proportion or concentration of whey protein in late summer. Based on a principal component analysis including variables such as citric acid, lactose and non-protein N, we suggest that the cows' energy supply during this period may be a critical factor in determining the milk protein composition, although our results were not conclusive. There was an interaction between the supplement of rumen undegradable protein and type of sward. When clover was grazed, a high supplement increased the concentrations of protein and casein in milk and the kappa-casein: total casein ratio. When rye-grass was grazed, the opposite response was found, and overall milk protein yield was not affected. The very low N content of clover in early summer reduced milk protein and casein protein during this period.

  16. Effects of Size and Stability of Native Fat Globules on the Formation of Milk Gel Induced by Rennet.

    Science.gov (United States)

    Luo, Jie; Wang, Yuhan; Guo, Huiyuan; Ren, Fazheng

    2017-03-01

    Rennet-induced gelation crucially impacts cheese structure. In this study, effects of the size and stability of native fat globules on the kinetics of rennet-induced coagulation were revealed by determining the caseinomacropeptide release rate and rheological properties of milk. Moreover, the mobility and stability of fat globules during renneting was revealed using diffusing wave spectroscopy and confocal laser scanning microscopy. By use of a 2-stage gravity separation combined centrifugation scheme, native fat globules were selectively separated into small (SFG, D4,3 = 1.87 ± 0.02 μm) and large fat globules (LFG, D4,3 = 5.65 ± 0.03 μm). The protein and fat content of SFG and LFG milk were then standardized to 3.2 g/100 mL and 1.2 g/100 mL, respectively. The milk containing different sized globules were then subjected to renneting experiments in the laboratory. Reduction of globule size accelerated the aggregation of casein micelles during renneting, giving a shorter gelation time and earlier 1/l(*) change. The gel produced from LFG milk was broken due to coalescent fat globules and generated coarser gel strands compared to the finer strands formed with SFG milk. Structural differences were also confirmed with a higher final storage modulus of the curd made from SFG milk than that from the LFG. In conclusion, the size of fat globules affects the aggregation of casein micelles. Moreover, fat globule coalescence and creaming during renneting, also affects the structure of the rennet gel. A better understanding of the size of globules effect on milk gelation could lead to the development of cheese with specific properties.

  17. Bovine chromosomal regions affecting rheological traits in rennet-induced skim milk gels

    DEFF Research Database (Denmark)

    Gregersen, Vivi Raundahl; Gustavsson, F; Glantz, M

    2015-01-01

    Optimizing cheese yield and quality is of central importance to cheese manufacturing. The yield is associated with the time it takes before the gel has an optimal consistency for further processing, and it is well known that gel formation differs between individual milk samples. By identifying...... genomic regions affecting traits related to rennet-induced gelation, the aim of this study was to identify potential candidate genes affecting these traits. Hence, rennet-induced gelation, including rennet coagulation time, gel strength, and yield stress, was measured in skim milk samples collected from...

  18. Contribution of enzymes from rennet, starter bacteria and milk to proteolysis and flavour development in Gouda cheese

    NARCIS (Netherlands)

    Visser, F.M.W.

    1977-01-01

    A method for the aseptic manufacture of cheeses, free either from rennet or from rennet and starter, is described, allowing the action of starter bacteria and milk protease to be studied without the interference of rennet. These cheeses, together with aseptic starter-free cheeses, were

  19. Effect of insoluble calcium concentration on endogenous syneresis rate in rennet-coagulated bovine milk.

    Science.gov (United States)

    Choi, J; Horne, D S; Lucey, J A

    2015-09-01

    The rennet coagulation of milk has been extensively studied. Mathematical modeling of the gelation process has been performed, mainly for the purpose of predicting the gel point. Rheological profiles of rennet gels during aging (long reaction times) have indicated that the gel stiffness (modulus) attains a maximum and thereafter decreases. We wanted to model this type of behavior and used the Carlson model, which includes terms for the proteolysis of κ-casein hairs (creating active sites) and the crosslinking of these activated sites. To account for the observed decrease in the gel modulus with time, we modified the Carlson model by adding an exponential decay term, which we ascribe to endogenous syneresis. We believe that this decay (i.e., syneresis rate) would likely be influenced by the mobility of bonds within casein micelles (in gels as indicated by the rheological loss tangent parameter). To modify the internal structural bonding of casein micelles, reconstituted skim milk was acidified to pH values 6.4, 6.0, 5.8, 5.6, and 5.4, or EDTA was added to milk at concentrations of 0, 2, 4, and 6mM, and the final pH values of EDTA-treated samples were subsequently adjusted to pH 6.0. These treatments were then used to prepare rennet gel samples that were monitored by dynamic low amplitude oscillatory rheometry. When the modified Carlson model was fitted to the actual experimental storage modulus values of each sample, it fitted the data reasonably well (especially the pH trial data). As the pH values of milk decreased, the modulus values at infinite reaction time (G'∞) increased; however, G'∞ decreased with an increase in the EDTA concentration. In the pH trial, the rate constants for the proteolysis of κ-casein hairs and the crosslinking of these activated sites exhibited a maximum at pH 5.6 and 6.0, respectively. The rate constant for endogenous syneresis increased at pH values syneresis was significantly positively correlated (r≥0.96) with the loss tangent

  20. Rennet-induced gelation of concentrated milk in the presence of sodium caseinate: differences between milk concentration using ultrafiltration and osmotic stressing.

    Science.gov (United States)

    Krishnankutty Nair, P; Corredig, M

    2015-01-01

    Concentrating milk is a common unit operation in the dairy industry. With the reduction of water, the particles interact more frequently with each other and the functionality of the casein micelles may depend on the interactions occurring during concentration. The objective of this research was to investigate the effect of concentration on the renneting properties of the casein micelles by comparing 2 concentration methods: ultrafiltration and osmotic stressing. Both methods selectively concentrate the protein fraction of milk, while the composition of the soluble phase is unaltered. To evaluate possible differences in the rearrangements of the casein micelles during concentration, renneting properties were evaluated with or without the addition of soluble caseins, added either before or after concentration. The results indicate that casein micelles undergo rearrangements during concentration and that shear during membrane filtration may play a role in affecting the final properties of the milk.

  1. Immunochromatographic Lateral-flow test strip for the rapid detection of added bovine rennet whey in milk and milk powder

    NARCIS (Netherlands)

    Martin-Hernandez, C.; Munoz, M.; Daury, C.; Weymuth, H.; Kemmers-Voncken, A.; Corbation, V.; Toribo, T.; Bremer, M.G.E.G.

    2009-01-01

    An immunochromatographic lateral-flow test dipstick test was developed for the fast detection of bovine rennet whey in liquid milk and milk powder. The test is based on the binding of casein glycomacropeptide (cGMP) by two specific anti-bovine ¿-casein monoclonal antibodies and has a visual detectio

  2. 7 CFR 58.436 - Rennet, pepsin, other milk clotting enzymes and flavor enzymes.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 3 2010-01-01 2010-01-01 false Rennet, pepsin, other milk clotting enzymes and flavor enzymes. 58.436 Section 58.436 Agriculture Regulations of the Department of Agriculture (Continued... clotting enzymes and flavor enzymes. Enzyme preparations used in the manufacture of cheese shall be...

  3. Influence of diet and of lamb slaughtering age on the coagulating properties of rennet paste

    Directory of Open Access Journals (Sweden)

    M. Albenzio

    2010-01-01

    Full Text Available Rennet composition varies along with several factors such as source (animal species, herbage, microbial and genetic, physical state (liquid, powder and paste, enzymatic composition (chymosin/ pepsin ratio, lipolitic enzymes. Main factors influencing rennet paste are diet (milk feeding, weaning and slaughtering age. Rennet paste composition influences cheese-making and ripening processes in cheese. Little is known about the effects of probiotic addition to milk substitute on the microbial status and enzyme profile of rennet, and on ripening characteristics of cheese. The aim of the study was to evaluate the effects of rearing systems and of lamb slaughtering age on microbial profile and time of coagulation of rennet pastes used for Pecorino Foggiano cheese-making.

  4. Effects of pH and Calcium on the textural properties of rennet gels produced by reconstituted milk%酸度和钙质量分数对复原乳酶凝胶质地特性的影响

    Institute of Scientific and Technical Information of China (English)

    王伟军; 张兰威; 李延华

    2011-01-01

    Whey protein is of the nutritional value. The nutritional value and yield of products could increase when whey protein is integrated into cheese. The textural properties of rennet gel produced from the reconstituted whole and skim milk powder after pre-treatments by adjusting calcium concentration and pH were investigated. With the principle component analysis for textural variables, the differences in the new components were clearly observed among the pre-treatments. These pre-treatments showed great effects on the viscosity and water- holding capacity of rennet gel. In addition, it was also found that some pre-treatments displayed similar properties to what were found in the gel made from raw milk.%考察了不同酸度、钙质量分数调节后复原乳酶凝胶的质地特性,并对其质地变量进行了主成分分析.结果表明,不同工艺处理样品间的差异可以清晰地表现在两个新变量中.酸度、钙质量分数调整可对凝胶的表观黏度和持水力产生很大影响.此外,通过对照分析可以发现,不同前处理的复原乳样品具有与原料乳相近的凝胶特性.

  5. Effect of carrageenan addition on the rennet-induced gelation of skim milk.

    Science.gov (United States)

    Wang, Fang; Zhang, Wei; Ren, Fazheng

    2016-09-01

    Carrageenan (CG) (κ-CG, ι-CG and λ-CG) was added to skim milk and the rennet-induced aggregation was studied. Caseinomacropeptide (CMP) release, diffusing wave spectroscopy (DWS) and rheology were used to follow the structural dynamics of casein micelles during gelation. The influence of carrageenan on the nature of protein interactions in the gels was investigated using a combination of ultracentrifugation and specific dissociating agents. For the recombined samples containing κ-CG and low concentrations of ι-CG and λ-CG, the CMP release was slowed down; however, the development of DWS and rheological parameters was similar to that of the control sample, and the increase in the incorporation of proteins through calcium bridges and hydrophobic interactions may be the most likely contributors. For the recombined samples containing high concentrations of ι-CG and λ-CG, other factors may impede the gel formation process. High concentrations of ι-CG and λ-CG strongly interfered with the rennet-induced aggregation, interrupted the interaction of caseins and therefore may contribute to good quality of low-fat cheese. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  6. Free amino acid content of goat's milk cheese made with animal rennet and plant coagulant.

    Science.gov (United States)

    Abellán, Adela; Cayuela, José María; Pino, Antonio; Martínez-Cachá, Adela; Salazar, Eva; Tejada, Luis

    2012-06-01

    Enzymes present in the flowers of Cynara cardunculus (cyprosins) are used in the production of some traditional Spanish and Portuguese cheeses, replacing animal rennet. The aim of this work was to study the changes that take place in free amino acids during the ripening of a goat's milk cheese (Murcia al Vino) manufactured with plant coagulant (PC) or animal rennet (AR). The total free amino acid (TFAA) concentration increased during ripening, with Ile, Val, Ala, Phe, Gaba, Arg and Lys representing more than 50% of the TFAA content at 60 days in both types of cheese. The TFAA concentration was significantly higher in cheeses made with PC (854 mg 100 g(-1) total solids (TS)) than those made with AR (735 mg 100 g(-1) TS). The concentration of most free amino acids, especially His, Ser, Gln, Thr, Ala, Met and Ile, was higher in the PC cheese. Cheese made using PC as coagulant presented higher contents of free amino acid throughout the ripening period than cheese made using AR. Therefore we can conclude that the use of PC to produce Murcia al Vino goat's cheese would accelerate the ripening process as a result of increased cyprosin proteolytic activity. Copyright © 2011 Society of Chemical Industry.

  7. Determination Of The Influence Of High Pressure Processing On Calf Rennet Using Response Surface Methodology: Effects On Milk Coagulation

    OpenAIRE

    de Castro Leite Junior; Bruno Ricardo; Lima Tribst; Alline Artigiani; Sampaio Bonafe; Carlos Francisco; Cristianini; Marcelo

    2016-01-01

    This study investigated the influence of high pressure processing (HPP) on the proteolytic and milk-clotting activities of calf rennet and milk coagulation using processed enzyme by rheological assay and confocal microscopy. The process was carried out at 25 degrees C, using pressure range from 50 to 300 MPa and time between 5 and 30 min. It was found that HPP (175-285 MPa for 14-23 min) increased the enzyme proteolytic activity by up to 23% and the milk-clotting activity by up to 17%. Furthe...

  8. Impact of thistle rennet from Carlina acanthifolia All. subsp. acanthifolia on bacterial diversity and dynamics of a specialty Italian raw ewes' milk cheese.

    Science.gov (United States)

    Cardinali, Federica; Osimani, Andrea; Taccari, Manuela; Milanović, Vesna; Garofalo, Cristiana; Clementi, Francesca; Polverigiani, Serena; Zitti, Silvia; Raffaelli, Nadia; Mozzon, Massimo; Foligni, Roberta; Franciosi, Elena; Tuohy, Kieran; Aquilanti, Lucia

    2017-08-16

    Caciofiore della Sibilla is an Italian specialty soft cheese manufactured with Sopravissana raw ewes' milk and thistle rennet prepared with young fresh leaves and stems of Carlina acanthifolia All. subsp. acanthifolia, according to an ancient tradition deeply rooted in the territory of origin (mountainous hinterland of the Marche region, Central Italy). In this study, the impact of thistle rennet on the bacterial dynamics and diversity of Caciofiore della Sibilla cheese was investigated by applying a polyphasic approach based on culture and DNA-based techniques (Illumina sequencing and PCR-DGGE). A control cheese manufactured with the same batch of ewes' raw milk and commercial animal rennet was analyzed in parallel. Overall, a large number of bacterial taxa were identified, including spoilage, environmental and pro-technological bacteria, primarily ascribed to Lactobacillales. Thistle rennet was observed clearly to affect the early bacterial dynamics of Caciofiore della Sibilla cheese with Lactobacillus alimentarius/paralimentarius and Lactobacillus plantarum/paraplantarum/pentosus being detected in the phyllosphere of C. acanthifolia All., thistle rennet and curd obtained with thistle rennet. Other bacterial taxa, hypothetically originating from the vegetable coagulant (Enterococcus faecium, Lactobacillus brevis, Lactobacillus delbrueckii, Leuconostoc mesenteroides/pseudomesenteroides), were exclusively found in Caciofiore della Sibilla cheese by PCR-DGGE. At the end of the maturation period, Illumina sequencing demonstrated that both cheeses were dominated by Lactobacillales; however curd and cheese produced with thistle rennet were co-dominated by Lactobacillus and Leuconostoc, whereas Lactoccous prevailed in curd and cheese produced with commercial animal rennet followed by Lactobacillus. Differences in the bacterial composition between the two cheeses at the end of their maturation period were confirmed by PCR-DGGE analysis. Copyright © 2017 Elsevier B

  9. The effect of milk processing on the microstructure of the milk fat globule and rennet induced gel observed using confocal laser scanning microscopy.

    Science.gov (United States)

    Ong, L; Dagastine, R R; Kentish, S E; Gras, S L

    2010-04-01

    Confocal laser scanning microscopy (CLSM) was successfully used to observe the effect of milk processing on the size and the morphology of the milk fat globule in raw milk, raw ultrafiltered milk, and standardized and pasteurized milk prepared for cheese manufacture (cheese-milk) and commercial pasteurized and homogenized milk. Fat globule size distributions for the milk preparations were analyzed using both image analysis and light scattering and both measurements produced similar data trends. Changes to the native milk fat globule membrane (MFGM) were tracked using a MFGM specific fluorescent stain that allowed MFGM proteins and adsorbed proteins to be differentiated on the fat globule surface. Sodium dodecyl sulfate polyacrylamide gel electrophoresis confirmed the identity of native MFGM proteins isolated from the surface of fat globules within raw, UF retentate, and cheese-milk preparations, whereas only casein was detected on the surface of fat globules in homogenized milk. The microstructure, porosity, and gel strength of the rennet induced gel made from raw milk and cheese-milk was also found to be comparable and significantly different to that made from homogenized milk. Our results highlight the potential use of CLSM as a tool to observe the structural details of the fat globule and associated membrane close to its native environment.

  10. Syneresis of rennet-induced milk gels as influenced by cheesemaking parameters.

    NARCIS (Netherlands)

    Bijgaart, van den H.J.C.M.

    1988-01-01

    The syneresis behaviour of rennet-induced skimmilk gels was studied at closely controlled conditions. The origin of the endogenous syneresis pressure and changes therein and in the permeability of the gel during syneresis are discussed. The latter appears to be of predominant importance for the oned

  11. Factors influencing the gelation and rennetability of camel milk using camel chymosin

    DEFF Research Database (Denmark)

    Hailu, Yonas; Hansen, Egon Bech; Seifu, Eyassu

    2016-01-01

    and decreasing pH. For all samples gelation was initiated at levels of camel milk κ-CN hydrolysis >95%. The gelation time (Tg) of camel milk was significantly reduced (from 717 to 526 s) at 30 °C when the concentration of chymosin was increased, but was independent of chymosin concentration at 40 °C. Reducing p......H also reduced Tg. The gel firmness increased at 40 °C (58 Pa) compared with 30 °C (44 Pa) and effect of CaCl2 addition on the gelation properties of camel milk was found to be dependent on pH; a significant improvement was only found at pH 6.3....

  12. Starch addition in renneted milk gels: partitioning between curd and whey and effect on curd syneresis and gel microstructure.

    Science.gov (United States)

    Brown, K M; McManus, W R; McMahon, D J

    2012-12-01

    Milk gels were made by renneting and acidifying skim milk containing 5 different starches, and then compressed by centrifugation to express whey and simulate curd syneresis during the manufacture of low-fat cheese. A series of 17 starches were examined, with 5 starches being selected for in-depth analysis: a modified waxy corn starch (WC), a waxy rice starch (WR), an instant tapioca starch (IT), a modified tapioca starch (MT), and dextrin (DX). Milks containing WC, WR, and DX were given a 72°C heat treatment, whereas those containing IT and MT had a 30-min treatment at 66°C that matched their optimum gelatinization treatments. Curd yields were calculated by weight, estimated starch content in whey was measured gravimetrically by alcohol precipitation, and starch retention in curd was calculated. Curd yields were 13.1% for the control milk (no added starch) and 18.4, 20.7, 21.5, 23.5, and 13.2% for the gels containing starches WC, WR, IT, MT, and DX, respectively. Estimated starch retentions in the curd were, respectively, 71, 90, 90, 21, and 1%. Laser scanning confocal microscopy was used to determine the location of the starches in the curd and their interaction with the protein matrix. Waxy corn, WR, and IT starches have potential to improve texture of low-fat cheese because they had high retention in the curd and they generated interruptions in the protein matrix network that may have helped limit extensive protein-protein interactions. Modified tapioca starch interfered with formation of the protein structure of the curd and produced a soft noncohesive gel, even though most (79%) of the MT starch was lost in the whey. Few distinct starch particles were present in the MT curd network. Dextrin was not retained in the curd and did not disrupt the protein network, making it unsuitable for use in low-fat cheese.

  13. Genetic aspects of milk coagulation properties in Italian Holstein cows

    Directory of Open Access Journals (Sweden)

    G. Bittante

    2010-01-01

    Full Text Available In Italy, the quota of national production of cow milk destined for cheese yield isabout 73% of total marketable milk (Osservatorio del latte, 2002. Hence, the improvement of renneting propertiesof milk is an important objective for the dairy sector. Favorable conditions of milk reactivity with rennet,curd formation rate and curd strength, as well as curd syneresis, have a positive effect on the wholecheese-making process and, later, on the ripening development of cheese.

  14. Phenotypic and genetic associations of milk traits with milk coagulation properties.

    Science.gov (United States)

    Poulsen, N A; Buitenhuis, A J; Larsen, L B

    2015-04-01

    The aim of this study was to examine milk composition and rennet-induced coagulation properties of milk from 892 individual Danish Holstein and Danish Jersey cows and determine the genetic influences on these properties by determining heritability and genomic correlations with single nucleotide polymorphisms identified by the bovine HD Beadchip (Illumina Inc., San Diego, CA). Despite no signs of clinical mastitis, milk from cows with somatic cell counts >500,000 cells/mL showed altered milk composition, indicating impaired barrier between the milk and the blood. Curd-firming rate (CFR) and rennet coagulation time (RCT) were used to describe milk coagulation properties (MCP). These traits describe the second phase of milk coagulation and were mutually negatively correlated, but only to some extent associated with the same compositional traits. In both breeds, CFR were highly correlated with protein content, whereas longer RCT were primarily associated with lower milk pH. Estimated heritabilities for milk production and compositional traits ranged from 0.09 for yield to 0.82 for citric acid in Danish Jersey cows, and from 0.21 for yield to 0.59 for citric acid in Danish Holstein cows. Heritabilities for MCP traits varied considerably between breeds, and were estimated to be 0.28 for RCT and 0.75 for CFR in Danish Holstein cows and 0.45 for RCT and 0.15 for CFR in Danish Jersey cows. This difference was further reflected in the genomic correlations between RCT and CFR which was -0.90 in Danish Holstein and 0.06 in Danish Jersey. These data suggest that potential for changing MCP through breeding exists, but the genetic background of the MCP traits might be different in different breeds; therefore, using Danish Holstein as background for Danish Jersey is not trivial. Thereby, the study underlines the need for breed-specific models. Copyright © 2015 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  15. Effect of microparticulated whey proteins on milk coagulation properties.

    Science.gov (United States)

    Sturaro, A; Penasa, M; Cassandro, M; Varotto, A; De Marchi, M

    2014-11-01

    The enhancement of milk coagulation properties (MCP) and the reuse of whey produced by the dairy industry are of great interest to improve the efficiency of the cheese-making process. Native whey proteins (WP) can be aggregated and denatured to obtain colloidal microparticulated WP (MWP). The objective of this study was to assess the effect of MWP on MCP; namely, rennet coagulation time (RCT), curd-firming time, and curd firmness 30 min after rennet addition. Six concentrations of MWP (vol/vol; 1.5, 3.0, 4.5, 6.0, 7.5, and 9.0%) were added to 3 bulk milk samples (collected and analyzed during 3 d), and a sample without MWP was used as control. Within each day of analysis, 6 replicates of MCP for each treatment were obtained, changing the position of the treatment in the rack. For control samples, 2 replicates per day were performed. In addition to MCP, WP fractions were measured on each treatment during the 3 d of analysis. Milk coagulation properties were measured on 144 samples by using a Formagraph (Foss Electric, Hillerød, Denmark). Increasing the amount of MWP added to milk led to a longer RCT. In particular, significant differences were found between RCT of the control samples (13.5 min) and RCT of samples with 3.0% (14.6 min) or more MWP. A similar trend was observed for curd-firming time, which was shortest in the control samples and longest in samples with 9.0% MWP (21.4 min). No significant differences were detected for curd firmness at 30 min across concentrations of MWP. Adjustments in cheese processing should be made when recycling MWP, in particular during the coagulation process, by prolonging the time of rennet activity before cutting the curd.

  16. Effect of soluble calcium on the renneting properties of casein micelles as measured by rheology and diffusing wave spectroscopy.

    Science.gov (United States)

    Sandra, S; Ho, M; Alexander, M; Corredig, M

    2012-01-01

    Addition of calcium chloride to milk has positive effects on cheese-making because it decreases coagulation time, creates firmer gels, and increases curd yield. Although addition of calcium chloride is a widely used industrial practice, the effect of soluble calcium on the preliminary stages of gelation is not fully understood. In addition, it is not known whether the manner of addition and equilibration of the soluble calcium would affect the rennetability of the casein micelles. Therefore, the aim of this paper was to study the details of the coagulation behavior of casein micelles in the presence of additional calcium, and to elucidate whether the manner in which this cation is added (directly as calcium chloride or by gradual exchange through dialysis) affects the functionality of the micelles. Calcium was added as CaCl(2) (1 mM final added concentration) directly to skim milk or indirectly using dialysis against 50 volumes of milk. Additional soluble calcium did not affect the primary phase of the renneting reaction, as demonstrated by the analysis of the casein macropeptide (CMP) released in solution; however, it shortened the coagulation time of the micelles and increased the firmness of the gel. The turbidity parameter of samples with or without calcium showed that similar amounts of CMP were needed for particle interactions to commence. However, the amount of CMP released at the point of gelation, as indicated by rheology, was lesser for samples with added calcium, which can be attributed to a greater extent of calcium bridging on the surface or between micelles. The results also showed that the manner in which calcium was presented to the micelles did not influence the mechanism of gelation.

  17. a New Method for Measuring Macroparticulate Systems Applied to Measuring Syneresis of Renneted Milk Gels.

    Science.gov (United States)

    Maynes, Jonathan R.

    Syneresis is an integral part of cheese manufacture. The rate and extent of syneresis affect the properties of cheese. There are many factors that affect syneresis, but measured results vary because of inaccuracies in measuring techniques. To better control syneresis, an accurate mathematical description must be developed. Current mathematical models describing syneresis are limited because of inherent error in measuring techniques used to develop them. Developing an accurate model requires an accurate way to measure syneresis. The curd becomes a particle in a whey suspension when the coagulum is cut. The most effective technique to measure particle size, without interference, is with light. Approximations to rigorous Maxwellian theory render useable results for a variety of particle sizes. Assumptions of Fraunhofer diffraction theory relate absorption to the cross sectional area of a particle that is much larger than the wavelength of light being used. By applying diffraction theory to the curd-whey system, this researcher designed a new apparatus to permit measurement of large particle systems. The apparatus was tested, and calibrated, with polyacrylic beads. Then the syneresis of curd was measured with this apparatus. The apparatus was designed to measure particles in suspension. Until some syneresis takes place, curd does not satisfy this condition. Theoretical assumptions require a monolayer of scattering centers. The sample container must be thin enough to preclude stacking of the particles. This presents a unique problem with curd. If the coagulum is cut in the sample cell, it adheres to the front and back surfaces and does not synerese. The curd must be coagulated and cut externally and transferred to the sample cell with a large amount of whey. This measurement technique has other limitations that may be overcome with commercially available accessories.

  18. Probiotic in rennet paste can affect lipase activity of rennet and lipolysis in ovine cheese

    Directory of Open Access Journals (Sweden)

    Marzia Albenzio

    2010-01-01

    Full Text Available Lambs were subjected to three different feeding regimes (mother suckling MS, artificial rearing AR, and artificial rearing with 7log10 cfu/ml Lactobacillus acidophilus supplementation to the milk substitute ARLb and slaughtered at 20d and 40d of age for each feeding treatment. Lambs abomasa were processed to rennet paste and lipases activity was evaluated. Rennet paste was used for Pecorino cheese production. Free fatty acids (FFAs and conjugated linoleic acids (CLAs were detected in cheese at 60d of ripening. Lipase activity was found higher in ARLb than in MS and AR rennet from lambs slaughtered at an older age. A reduction of all FFAs was observed in all cheeses when passing from 20 d to 40d of slaughtering. CLAs were more abundant in ARLb cheeses at both 20 and 40d. Milk substitute with Lb. acidophilus improves enzymatic features of rennet, and health and nutritional characteristics of ovine cheese.

  19. GENETIC ASPECTS OF MILK COAGULATION PROPERTIES IN DAIRY CATTLE

    Directory of Open Access Journals (Sweden)

    M. Cassandro

    2007-06-01

    Full Text Available Authors reviewed the genetic aspects of milk coagulation ability focusing on heritability and genetic correlation values and on the breed and milk protein loci effects on rennet coagulation time and curd firmness. The review discussed milk and cheese yield production all over the world concluding that the per capita retail demand for cheese will increase with a mean annual growth rate of 0.8%. Therefore, in the future, cheese production will continue to be one of the major livestock food products around the world. The development of new payment systems for milk considering the intrinsic value for cheese making ability, could be an important opportunity for select best individual within dairy cattle breeds and to preserve, among dairy cattle breeds, those with high milk coagulation properties. Often these genetic resources, beyond their genetic value, also exercise a positive influence on sustainability of milk production in fragile environments, such as mountain areas, preserving an important cultural value (history, traditions, arts, and literature.

  20. Genetic parameters of coagulation properties, milk yield, quality, and acidity estimated using coagulating and noncoagulating milk information in Brown Swiss and Holstein-Friesian cows.

    Science.gov (United States)

    Cecchinato, A; Penasa, M; De Marchi, M; Gallo, L; Bittante, G; Carnier, P

    2011-08-01

    The aim of this study was to estimate heritabilities of rennet coagulation time (RCT) and curd firmness (a(30)) and their genetic correlations with test-day milk yield, composition (fat, protein, and casein content), somatic cell score, and acidity (pH and titratable acidity) using coagulating and noncoagulating (NC) milk information. Data were from 1,025 Holstein-Friesian (HF) and 1,234 Brown Swiss (BS) cows, which were progeny of 54 HF and 58 BS artificial insemination sires, respectively. Milk coagulation properties (MCP) of each cow were measured once using a computerized renneting meter and samples not exhibiting coagulation within 31 min after rennet addition were classified as NC milk. For NC samples, RCT was unobserved. Multivariate analyses, using Bayesian methodology, were performed to estimate the genetic relationships of RCT or a(30) with the other traits and statistical inference was based on the marginal posterior distributions of parameters of concern. For analyses involving RCT, a right-censored Gaussian linear model was used and records of NC milk samples, being censored records, were included as unknown parameters in the model implementing a data augmentation procedure. Rennet coagulation time was more heritable [heritability (h(2))=0.240 and h(2)=0.210 for HF and BS, respectively] than a(30) (h(2)=0.148 and h(2)=0.168 for HF and BS, respectively). Milk coagulation properties were more heritable than a single test-day milk yield (h(2)=0.103 and h(2)=0.097 for HF and BS, respectively) and less heritable than milk composition traits whose heritability ranged from 0.275 to 0.275, with the only exception of fat content of BS milk (h(2)=0.108). A negative genetic correlation, lower than -0.85, was estimated between RCT and a(30) for both breeds. Genetic relationships of MCP with yield and composition were low or moderate and favorable. The genetic correlation of somatic cell score with RCT in BS cows was large and positive and even more positive were

  1. [Occupational allergies against pepsin, chymosin and microbial rennet].

    Science.gov (United States)

    van Kampen, V; Lessmann, H; Brüning, T; Merget, R

    2013-05-01

    Rennet is a mixture of the proteolytic enzymes pepsin and chymosin (rennin), which is usually obtained from the fourth stomach of young ruminants. While pepsin is also used in the pharmaceutical industry, both enzymes (pepsin and chymosin) are used for the coagulation of milk protein in the manufacture of cheese. Additionally, microbial rennet, which is naturally produced by certain microorganisms, has been used as a substitute for natural rennet in the cheese production for decades. Exposure to enzyme dusts has long been known to cause occupational immediate hypersensitivities. The present paper reviews the results of an evaluation of the literature data concerning occupational airway sensitisation due to natural and microbial rennet. Cases of specific airway sensitisation caused by rennet could be shown clearly by several studies. Positive skin prick and challenge tests as well as specific IgE antibodies have been described, thus suggesting an immunological mechanism.

  2. Effects of ultra-high pressure homogenization on the cheese-making properties of milk.

    Science.gov (United States)

    Zamora, A; Ferragut, V; Jaramillo, P D; Guamis, B; Trujillo, A J

    2007-01-01

    The effects of single- or 2-stage ultra-high pressure homogenization (UHPH; 100 to 330 MPa) at an inlet temperature of 30 degrees C on the cheese-making properties of bovine milk were investigated. Effects were compared with those from raw, heat-pasteurized (72 degrees C for 15 s), and conventional homogenized-pasteurized (15 + 3 MPa, 72 degrees C for 15 s) treatments. Rennet coagulation time, rate of curd firming, curd firmness, wet yield, and moisture content of curds were assessed. Results of particle size and distribution of milk, whey composition, and gel microstructure observed by confocal laser scanning microscopy were analyzed to understand the effect of UHPH. Single-stage UHPH at 200 and 300 MPa enhanced rennet coagulation properties. However, these properties were negatively affected by the use of the UHPH secondary stage. Increasing the pressure led to higher yields and moisture content of curds. The improvement in the cheese-making properties of milk by UHPH could be explained by changes to the protein-fat structures due to the combined effect of heat and homogenization.

  3. Comparative study of white brined cheeses obtained from whole milk and milk-olive oil emulsion: Physicochemical and sensory properties

    Directory of Open Access Journals (Sweden)

    Imène Felfoul

    2016-11-01

    Full Text Available The present paper is focused on the physicochemical and sensory parameters of low-fat white brined cheese-like product obtained from the substitution of milk fat by milk-olive oil emulsion, in comparison with full and low-fat control cheeses. Formulated milk samples were initially pasteurized at 63 °C for 30 min, cooled down to 35 °C, and subsequently 0.35 mL L-1 of microbial rennet were added. The obtained cheeses were stored at 4 °C during 24 hours and then analyzed for physicochemical and sensory properties. The replacement of milk fat in white brined cheese resulted in a lower total solids content due to the higher water-binding capacity of fat replacers used. Fat content was significantly higher for low-fat white brined cheese-like product than in low-fat control cheese. This result was attributed to fat retention capacity of the fat replacers used. Lipolysis index was the highest in the case of low-fat white brined cheese-like product due to changes in cheese microstructure after fat replacers incorporation in low-fat products. Milk-olive oil emulsion showed the lowest cheese-making yield compared to its full and low-fat counterparts. The cheese like- product sample received a significantly lower overall impression score by the panelists than full and low-fat cheeses.

  4. Genetic parameters of milk coagulation properties and their relationships with milk yield and quality traits in Italian Holstein cows.

    Science.gov (United States)

    Cassandro, M; Comin, A; Ojala, M; Dal Zotto, R; De Marchi, M; Gallo, L; Carnier, P; Bittante, G

    2008-01-01

    Milk coagulation properties (MCP) are an important aspect in assessing cheese-making ability. Several studies showed that favorable conditions of milk reactivity with rennet, curd formation rate, and curd strength, as well as curd syneresis, have a positive effect on the entire cheese-making process and subsequently on the ripening of cheese. Moreover, MCP were found to be heritable, but little scientific literature is available about their genetic aspects. The aims of this study were to estimate heritability of MCP and genetic correlations among MCP and milk production and quality traits. A total of 1,071 Italian Holstein cows (progeny of 54 sires) reared in 34 herds in Northern Italy were sampled from January to July 2004. Individual milk samples were collected during the morning milking and analyzed for coagulation time (RCT), curd firmness (a30), pH, titratable acidity, fat, protein, and casein contents, and somatic cell count. About 10% of individual milk samples did not coagulate in 31 min, so they were removed from the analyses. Estimates of heritability for RCT and a30 were 0.25 +/- 0.04 and 0.15 +/- 0.03, respectively. Estimates of genetic correlations between MCP traits and milk production traits were negligible except for a30 with protein and casein contents (0.44 +/- 0.10 and 0.53 +/- 0.09, respectively). Estimates of genetic correlations between MCP traits and somatic cell score were strong and favorable, as well as those between MCP and pH and titratable acidity. Selecting for high casein content, milk acidity, and low somatic cell count might be an indirect way to improve MCP without reducing milk yield and quality traits.

  5. The “maturation” of milk for Parmigiano- Reggiano cheesemaking: effects on mineral equilibria and technological properties

    Directory of Open Access Journals (Sweden)

    P. Mariani

    2010-04-01

    Full Text Available The “maturation” of milk for Parmigiano-Reggiano cheese is characterised by natural creaming process: the full cream milk is placed in large flat vats, for about 10-12 hours, to obtain the gravity separation of milk fat. The modifications of mineral equilibria and technological properties of milk during the “maturation” phase, were studied. To this aim 24 full cream (FC milk samples and the corresponding partially skimmed (PS milk, by natural creaming, were analysed. PS milk evidenced higher values of both colloidal Ca/casein (+4.28%; P£0.01 and colloidal P/casein (+4.02%; P£0.01 ratios than FC milk. An increase of pH (+0.028; P£0.01 and titratable acidity (+0.03 °SH/50ml; P£0.01 was observed during the milk “maturation”. The PS milk was characterised by a higher milk clotting time (r (+7.91%; P£0.01 and a lower curd firmness (a30 (−16.75%; P£0.01 than FC milk. Concerning rheological properties, PS milk curd was characterised by higher values of both resistance to compression (+14.82%; P£0.01 and resistance to cut (+15.12%; P£0.01 than FC milk. The variations of milk characteristics observed in PS milk seems to indicate a structural modification of the native micelle during the “maturation” phase; this feature contributed to variations of rennet-coagulation and rheological properties observed in PS milk.

  6. Effect of commercial grape extracts on the cheese-making properties of milk.

    Science.gov (United States)

    Felix da Silva, Denise; Matumoto-Pintro, Paula T; Bazinet, Laurent; Couillard, Charles; Britten, Michel

    2015-03-01

    Grape extracts can be added to milk to produce cheese with a high concentration of polyphenols. Four commercial extracts from whole grape, grape seed, and grape skin (2 extracts) were characterized and added to milk at concentrations of 0, 0.1, 0.2, and 0.3% (wt/vol). The effect of grape extracts on the kinetics of milk clotting, milk gel texture, and syneresis were determined, and model cheeses were produced. Whole grape and grape seed extracts contained a similar concentration of polyphenolic compounds and about twice the amount found in grape skin extracts. Radical scavenging activity was directly proportional to the phenolic compounds content. When added to milk, grape extracts increased rennet-induced clotting time and decreased the clotting rate. Although differences were observed between the extracts, the concentration added to milk was the main factor influencing clotting properties. With increasing concentrations of grape extracts, milk gels showed increased brittleness and reduced firmness. In addition, syneresis of milk gels decreased with increasing concentrations of grape extracts, which resulted in cheeses with a higher moisture content. The presence of grape extracts in milk slightly increased protein recovery in cheese but had no effect on fat recovery. With whole grape or grape seed extracts added to milk at 0.1% (wt/vol), the recovery coefficient for polyphenols was about 0.63, and decreased with increasing extract concentration in milk. Better polyphenol recovery was observed for grape seed extracts (0.87), with no concentration effect. Commercial extracts from whole grape, grape seed, or grape skin can be added to milk in the 0.1 to 0.3% (wt/vol) concentration range to produce cheese with potential health benefits, without a negative effect on cheese yield.

  7. Process for producing α-lactalbumin-enriched whey and evaluation of functional properties of rennet casein%α-乳白蛋白提取工艺研究及副产物功能性质评价

    Institute of Scientific and Technical Information of China (English)

    闫序东; 王彩云; 云战友; 尹睿杰

    2011-01-01

    研究了热附聚法结合凝乳酶处理从牛乳中直接提取α-乳白蛋白的工艺,得到富含α-乳白蛋白的乳清和副产物--附聚β-乳清蛋白的凝乳酶干酪素.富含α-乳白蛋白的乳清中α-乳白蛋白与β-乳球蛋白的浓度比达到3.03.达到了商业化产品的水平.副产物--附聚β-乳清蛋白的凝乳酶干酪素与市售凝乳酶干酪素在溶解性、持水性和乳化性方面存在的差异较小,将附聚β-乳清蛋白的凝乳酶干酪素作为原料应用于仿真干酪中,质构测定结果未显示出在质构方面与普通凝乳酶干酪素对照样品存在明显差异.%A process for producing α-lactalbumin-enriched fraction from milk was investigated. The process involved heating pH-adjusted skim milk and rennet treatment. The ratio of the concentration of α-lactalbumin to β-lactoglobulin was high enough to meet the level of commercial products. In addition to α-lactalbumin-enriched whey, rennet casein complex with whey proteins was obtained. The difference of solubility,water-holding capacity and emulsifying capacity between the casein/whey proteins aggregates and normal rennet casein were small and no obvious differences of texture of cheese analogue made of the casein/whey proteins aggregates and normal rennet casein were found.

  8. Influence of lamb rennet paste on the lipolytic and sensory profile of Murcia al Vino cheese.

    Science.gov (United States)

    Ferrandini, E; Castillo, M; de Renobales, M; Virto, M D; Garrido, M D; Rovira, S; López, M B

    2012-06-01

    The influence of lamb rennet paste (71.1% chymosin, 177 international milk-clotting units/mL, 4.57U/g of lipase activity) during the ripening of Murcia al Vino goat cheese was studied. The aim of this study was to improve the knowledge of the effect of lamb rennet paste on the lipolytic patterns in this type of cheese by reference to the evolution of total and free fatty acids. A sensory analysis was carried out to compare cheeses made with commercial and paste rennet. The rennet paste showed higher lipolytic activity, enhancing the production of short-chain free fatty acids. In addition, the cheese produced with lamb rennet paste had a slightly more bitter and piquant taste, making it an attractive commercial alternative that can be used to develop new varieties of goat cheese. Copyright © 2012 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  9. Distinct composition of bovine milk from Jersey and Holstein-Friesian cows with good, poor, or noncoagulation properties as reflected in protein genetic variants and isoforms.

    Science.gov (United States)

    Jensen, H B; Poulsen, N A; Andersen, K K; Hammershøj, M; Poulsen, H D; Larsen, L B

    2012-12-01

    The objective of this study was to examine variation in overall milk, protein, and mineral composition of bovine milk in relation to rennet-induced coagulation, with the aim of elucidating the underlying causes of milk with impaired coagulation abilities. On the basis of an initial screening of 892 milk samples from 42 herds with Danish Jersey and Holstein-Friesian cows, a subset of 102 samples was selected to represent milk with good, poor, or noncoagulating properties (i.e., samples that within each breed represented the most extremes in regard to coagulation properties). Milk with good coagulation characteristics was defined as milk forming a strong coagulum based on oscillatory rheology, as indicated by high values for maximum coagulum strength (G'(max)) and curd firming rate (CFR) and a short rennet coagulation time. Poorly coagulating milk formed a weak coagulum, with a low G'(max) and CFR and a long rennet coagulation time. Noncoagulating milk was defined as milk that failed to form a coagulum, having G'(max) and CFR values of zero at measurements taken within 1h after addition of rennet. For both breeds, a lower content of total protein, total casein (CN) and κ-CN, and lower levels of minerals (Ca, P, Mg) were identified in poorly coagulating and noncoagulating milk in comparison with milk with good coagulation properties. Liquid chromatography/electrospray ionization-mass spectrometry revealed the presence of a great variety of genetic variants of the major milk proteins, namely, α(S1)-CN (variants B and C), α(S2)-CN (A), β-CN (A(1), A(2), B, I, and F), κ-CN (A, B, and E), α-lactalbumin (B), and β-lactoglobulin (A, B, and C). In poorly coagulating and noncoagulating milk samples of both breeds, the predominant composite genotype of α(S1)-, β-, and κ-CN was BB-A(2)A(2)-AA, which confirmed a genetic contribution to impaired milk coagulation. Interestingly, subtle variations in posttranslational modification of CN were observed between the

  10. Milk quality, coagulation properties, and curd firmness modeling of purebred Holsteins and first- and second-generation crossbred cows from Swedish Red, Montbéliarde, and Brown Swiss bulls.

    Science.gov (United States)

    Malchiodi, F; Cecchinato, A; Penasa, M; Cipolat-Gotet, C; Bittante, G

    2014-07-01

    The objective of the present study was to investigate how the crossbreeding of Holstein (HO) cows with bulls from Nordic and Alpine European breeds affect milk quality traits, traditional milk coagulation properties (MCP), and curd firmness modeling obtained from individual milk samples. A total of 506 individual milk samples were collected from evening milking at 3 commercial farms located in Northern Italy. Over the past decade, the 3 farms have followed crossbreeding programs in part of their herds, whereas the remainder of the animals consisted of purebred HO. The basic scheme was a 3-breed rotation based on the use of Swedish Red (SR) semen on HO cows (SR × HO), the use of Montbéliarde (MO) semen on first-cross cows [MO × (SR × HO)], and the use of HO semen in the third cross. In all herds, a smaller proportion of purebred HO were mated to M and Brown Swiss (BS) bulls, and these first crosses were mated to SR and MO bulls, respectively. Milk samples were analyzed for milk composition and MCP, and parameters for curd firmness were modeled. Compared with purebred HO, crossbred cows produced less milk with lower lactose content, higher fat and protein content, and a tendency for higher casein content. Crossbred cows generally produced milk with a more favorable curd-firming rate (k₂₀) and curd firmness 30 min after rennet addition, among traditional MCP, and better trends of curd firmness measures as shown by model parameters: estimated rennet coagulation time, asymptotical potential value of curd firmness, and curd-firming instant rate constant. Among crossbred cows, SR × HO presented longer rennet coagulation time compared with MO × HO and BS × HO cows, and MO × HO showed shorter k₂₀ compared with BS × HO cows. Among second-generation cows, those sired by SR bulls showed a lower incidence of noncoagulated samples, higher curd firmness 30 min after rennet addition and asymptotical potential value of curd firmness, and faster curd-firming instant

  11. Eff ect of homogenization on the properties and microstructure of Mozzarella cheese from buff alo milk

    Directory of Open Access Journals (Sweden)

    S. Abd El-Rafee

    2012-06-01

    Full Text Available Background. The name pasta fi lata refers to a unique plasticizing and texturing treatments of the fresh curd in hot water that imparts to the fi nished cheese its characteristic fi brous structure and melting properties. Mozzarella cheese made from standardized homogenized and non-homogenized buffalo milk with 3 and 1.5%fat. The effect of homogenization on rheological, microstructure and sensory evaluation was carried out. Material and methods. Fresh raw buffalo milk and starter cultures of Streptococcus thermophilus and Lactobacillus delbrueckii ssp. bulgaricus were used. The coagulants were calf rennet powder (HA-LA. Standardized buffalo milk was homogenized at 25 kg/cm2 pressure after heating to 60°C using homogenizer. Milk and cheese were analysed. Microstructure of the cheese samples was investigated either with an application of transmission or scanning electron microscope. Statistical analyses were applied on the obtained data. Results. Soluble nitrogen total volatile free fatty acids, soluble tyrosine and tryptophan increased with using homogenized milk and also, increased with relatively decrease in case of homogenized Mozzarella cheese. Meltability of Mozzarella cheese increased with increasing the fat content and storage period and decrease with homogenization. Mozzarella cheese fi rmness increased with homogenization and also, increased with progressing of storage period. Flavour score, appearance and total score of Mozzarella cheese increased with homogenization and storage period progress, while body and texture score decreased with homogenization and increased with storage period progress. Microstructure of Mozzarella cheese showed the low fat cheese tends to be harder, more crumbly and less smooth than normal. Curd granule junctions were prominent in non-homogenized milk cheese. Conclusion. Homogenization of milk cheese caused changes in the microstructure of the Mozzarella cheese. Microstructure studies of cheese revealed that

  12. Changes of quality of rennets during storing

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    Monika Kozelková

    2012-01-01

    Full Text Available This work deals about evaluation of qualitative parameters of rennets. During the six months storing of rennets were determined following qualitative parameters: pH, rennet coagulation time, activity (strange of rennet and dose of rennet, and finally were used instrumental methods: Near infrared spectroscopy (NIR for recognizing age of rennets and spectrophotometric methods of determining the color of rennets. The theory found in the references suggests, that the activity of rennet should decrease by an average of 1–2 % per month, but the results are showing, that are changing quality of rennets namely mostly activity (strange of rennet, which was decreased by 33% per half year. In analysis of color of rennets weren’t observed major changes by the whole group. Some statistical differences were detected in the partial values L*a*b*, most advantageous were evaluation by rennet total color change during storage, which were higher than noticeable change in four samples. The least color changes (P > 0.05 were observed in microbial rennets, with no values observed (ΔEab < 2 that can be recognized even by the human eye when subjected to parallel comparison. It was found that the NIR analysis can be used to recognizing of rennets, which are different ages.

  13. Influence and comparison of thermal, ultrasonic and thermo-sonic treatments on microbiological quality and sensory properties of rennet cheese whey

    Directory of Open Access Journals (Sweden)

    Rajka Božanić

    2012-09-01

    Full Text Available Ultrasonication and thermo-sonication belong to alternative, non-thermal food processing methods. The aim of this study was to investigate the influence of different ultrasound power inputs (240 W, 320 W, 400 W without and in combination with heat pre-treatment on microbial inactivation and sensory properties of rennet cheese whey in comparison with conventional pasteurization batch processes. Ultrasonication treatments had no impact on reduction of any group of studied microorganisms. Microbial inactivation caused by thermo-sonication treatments with pre-heating to 35 °C or 45 °C increased with nominal power input and/or exposure times and was probably due to the heat improved ultrasonic cavitation. Thermo-sonication treatments at nominal power input (400 W and preheating to 55 °C were the most effective resulting in greater microbial reduction compared to that observed by simulating pasteurization processes, but occurred probably due to developed heat solely. Sensory properties after ultrasonication and thermo-sonication were considerably improved in comparison with that after simulated pasteurization processes. Mouth feel of whey samples was considerably better, there was no occurrence of sediment and colour remained unchanged in almost all samples.

  14. Effects of dairy factory, milk casein content and titratable acidity on coagulation properties in Trentingrana dairy industry.

    Science.gov (United States)

    Penasa, Mauro; Toffanin, Valentina; Cologna, Nicola; Cassandro, Martino; De Marchi, Massimo

    2016-05-01

    The objective of the present study was to investigate the effect of environmental factors, milk casein content and titratable acidity on milk coagulation properties (MCP) of samples routinely collected in the Trento province (northeast Italy) under field conditions. Rennet coagulation time (RCT, min), curd-firming time (k20, min) and curd firmness (a30, mm) were determined by Formagraph on 14 971 samples from 635 herds associated to 17 dairy factories. Besides MCP, fat, protein, and casein percentages, titratable acidity (TA), and somatic cell and bacterial counts were available. A standardised index of milk aptitude to coagulate (IAC) was derived using information of RCT and a30. An analysis of variance was conducted on MCP and IAC using a fixed effects linear model. Approximately 3% of milk samples did not form a curd within the testing time (30 min) and k20 was missing for 26% of milks. The percentage of samples without information on k20 largely differed among dairy factories (1·7-20·9%). Significant differences were estimated between the best and the worst dairy factory for RCT (-2 min), k20 (-1·2 min), a30 (+3·4 mm) and IAC (+2·6 points). Milk casein content and TA were important factors in explaining the variation of MCP and IAC, supporting the central role of these two traits on technological properties. The Trento province is heterogeneous in terms of dairy systems and this could explain the differences among dairy factories.

  15. Variations at regulatory regions of the milk protein genes are associated with milk traits and coagulation properties in the Sarda sheep.

    Science.gov (United States)

    Noce, A; Pazzola, M; Dettori, M L; Amills, M; Castelló, A; Cecchinato, A; Bittante, G; Vacca, G M

    2016-12-01

    Regulatory variation at the ovine casein genes could have important effects on the composition and coagulation properties of milk. Herewith, we have partially resequenced the promoters and the 3'-UTR of the four casein genes in 25 Sarda sheep. Alignment of these sequences allowed us to identify a total of 29 SNPs. This level of polymorphism (one SNP every 250 bp) is remarkably high if compared with SNP densities estimated in human genic regions (approximately one SNP per bp). The 29 SNPs identified in our resequencing experiment, plus three previously reported SNPs mapping to the lactalbumin, alpha (LALBA) and β-lactoglobulin (BLG, also known as progestagen-associated endometrial protein, PAEP) genes, were genotyped with a multiplex TaqMan Open Array Real-Time PCR assay in 760 Sarda sheep with records for milk composition and coagulation properties. Association analysis revealed the existence of significant associations of CSN1S2 and CSN3 genotypes with milk protein and casein contents. Moreover, genotypes at CSN1S1 were significantly associated with rennet coagulation time, curd firming time and curd firmness, whereas CSN2 was associated with curd firming time. These results suggest that SNPs mapping to the promoters and 3'-UTRs of ovine casein genes may exert regulatory effects on gene expression and that they could be used for improving sheep milk quality and technological traits at the population level through marker assisted selection.

  16. Production optimization of probiotic soft cheese made from goat's and cow's milk

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    Ida Drgalić

    2006-07-01

    Full Text Available The aim of this study was to determine optimal rennet share and fat content in milk for probiotic soft cheeseproduction made from goat's and cow's milk using DVS mixed probiotic culture ABT-4 (Lactobacillus acidophilus, Bifidobacterium spp. and Streptococcus thermophilus, with desirable sensory properties, which will be acceptable by consumers. The best sensory scores had samples of probiotic soft cheese produced in laboratory conditions from milk with 1% of milk fat, pasteurized at 65°C/30 min., fermented at 38°C with 2% culture. To achieve characteristic consistency of traditional soft cheese, 0.01% of rennet was added to goat's milk. Probiotic soft cheese made from cow's and goat's milk, produced under optimal conditions, were 100% acceptable by the tested consumers.

  17. Secretory Expression, Purification and Identification of Rennet from Mucor pusillus%微小毛霉凝乳酶的分泌表达、产物纯化及鉴定

    Institute of Scientific and Technical Information of China (English)

    王景会; 李玉秋; 郑丽; 李倬琳; 高岩; 杨贞耐

    2011-01-01

    The rennet from Mucor pusillus is one of the major sources of tnicrobial rennet, but it has some defects compared with the bovine chymosin. Aspartic proteinases from fungi are usually more heat resistant . When these enzymes are used for cheese making, the residue of enzymatic activity after heat treatment (55 ℃) following milk coagulation may still exist and cause proteolysis during cheese storage, bitter taste, softness and lower yield of the cheese products. In order to develop a rennet product with suitable milk clotting properties, the gene of rennet was cloned from Mucor pusillus, and the expression vector pPIC9K/M was constructed. The plasmids of pPIC9K/M was linearized with Sac I , and transformed into Pichia pastoris GS115 competent cells. The rennet was secretory expressed in Pichia pastoris successfully , and a strong band at about 46 kD was shown by SDS - PAGE. Activity tests showed that the rennet activity in the culture supernatant was 311.8 U/mL. The purity of recombinant rennet reached 92% with a 51.89% activity recovery.%采用基因工程的方法对微小毛霉(Mucor pusillus)凝乳酶进行分子改造,获得适于乳品工业生产用的凝乳酶,克隆到了微小毛霉凝乳酶基因,构建了酵母表达质粒pPIC9K/M。线性化后电击转入毕赤酵母GS115,在甲醇诱导下进行凝乳酶的初步发酵试验,通过pH反应及酶抑制反应试验证明,重组凝乳酶获得了分泌表达。SDS-PAGE分析表明重组凝乳酶的分子量约为46kD,与理论值(45.3 kD)基本相符,培养基上清液中凝乳酶的活性为311.8 U/mL,纯化的总回收率为51.89%,纯度达到92%。

  18. Optimization of rennet coagulation technology in the process of production of rennet casein%酶凝干酪素生产过程中酶凝工艺的优化

    Institute of Scientific and Technical Information of China (English)

    刘佳; 李青; 赵秀明; 赵征

    2012-01-01

    The effect of the amount of rennet added, rennet coagulation temperature and time on the technology of rennet casein were studied. The optimal rennet coagulation processing parameters of the production of rennet casein were determined by sensory evaluation on the process of coagulation. The results showed that the coagulation temperature and time have a significant effect on rennet coagulation status of rennet casein production. The optimal conditions of rennet coagulation were: the addition of rennet was 0.078%, the temperature of coagulation was 32 ℃ and coagulation time was 28 min. The physicochemical properties of rennet casein produced under this condition were similar to those of commercial rennet casein.%研究了凝乳酶添加量、凝乳温度和凝乳时间对酶凝干酪素酶凝工艺的影响,通过对凝乳过程的感官评价,最终确定了酶凝干酪素的最佳酶凝工艺参数.结果表明:凝乳温度和凝乳时间对酶凝干酪素酶凝状态有显著影响,确定最优工艺条件为:凝乳酶添加量的体积分数为0.078%,凝乳温度为32℃,凝乳时间28 min.此条件下生产的酶凝干酪素与市售酶凝干酪素理化指标接近.

  19. Characterization of the syneresis and the firmness of the milk gel using an ultrasonic technique

    Science.gov (United States)

    Taifi, N.; Bakkali, F.; Faiz, B.; Moudden, A.; Maze, G.; Décultot, D.

    2006-02-01

    A non-invasive ultrasonic method was used to control the change in physical properties of milk gel and the syneresis, which is an essential step in the manufacture of cheese. The velocity and the attenuation were recorded for ten hours. They provide a good indicator of syneresis occurring. The firmness of the milk gel increases with the variation in velocity (ΔV). The effects of the temperature, calcium chloride and rennet concentration on the syneresis were studied.

  20. Prediction and repeatability of milk coagulation properties and curd-firming modeling parameters of ovine milk using Fourier-transform-infrared spectroscopy and Bayesian models.

    Science.gov (United States)

    Ferragina, A; Cipolat-Gotet, C; Cecchinato, A; Pazzola, M; Dettori, M L; Vacca, G M; Bittante, G

    2017-03-16

    The aim of this study was to apply Bayesian models to the Fourier-transform infrared spectroscopy spectra of individual sheep milk samples to derive calibration equations to predict traditional and modeled milk coagulation properties (MCP), and to assess the repeatability of MCP measures and their predictions. Data consisted of 1,002 individual milk samples collected from Sarda ewes reared in 22 farms in the region of Sardinia (Italy) for which MCP and modeled curd-firming parameters were available. Two milk samples were taken from 87 ewes and analyzed with the aim of estimating repeatability, whereas a single sample was taken from the other 915 ewes. Therefore, a total of 1,089 analyses were performed. For each sample, 2 spectra in the infrared region 5,011 to 925 cm(-1) were available and averaged before data analysis. BayesB models were used to calibrate equations for each of the traits. Prediction accuracy was estimated for each trait and model using 20 replicates of a training-testing validation procedure. The repeatability of MCP measures and their predictions were also compared. The correlations between measured and predicted traits, in the external validation, were always higher than 0.5 (0.88 for rennet coagulation time). We confirmed that the most important element for finding the prediction accuracy is the repeatability of the gold standard analyses used for building calibration equations. Repeatability measures of the predicted traits were generally high (≥95%), even for those traits with moderate analytical repeatability. Our results show that Bayesian models applied to Fourier-transform infrared spectra are powerful tools for cheap and rapid prediction of important traits in ovine milk and, compared with other methods, could help in the interpretation of results.

  1. Effects of structural rearrangements on the rheology of rennet-induced casein particle gels

    NARCIS (Netherlands)

    Mellema, M.; Walstra, P.; Opheusden, van J.H.J.; Vliet, van T.

    2002-01-01

    During ageing of casein or skim milk gels, structural changes take place that affect gel parameters, such as pore size and storage modulus. These changes can be explained in terms of rearrangements of the gel network at various length scales. In this paper, rheological experiments on rennet-induced

  2. Effects of Stearoyl-CoA Desaturase 1 and Sterol Regulatory Element Binding Protein Gene Polymorphisms on Milk Production, Composition and Coagulation Properties of Individual Milk of Brown Swiss Cows

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    Alice Maurmayr

    2011-10-01

    Full Text Available Associations between stearoyl-CoA desaturase (SCD and sterol regulatory element binding protein (SREBP-1 gene polymorphisms and milk production, composition (fat, protein, and casein content, acidity (pH and titratable acidity and coagulation properties (MCP, namely rennet coagulation time (RCT, min and curd firmness (a30, mm were investigated on individual Brown Swiss milk. A total of 294 cows from 16 herds and progeny of 15 sires were milk-sampled once. Th e additive effects of SCD and SREBP-1 genotypes on the aforementioned traits were analyzed through Bayesian linear models. The SCD gene was associated with protein content, casein content and a30. Lower protein, casein and a30 was observed for milk yielded by SCD V than A cows, whereas for other traits the effect was trivial. Animals carrying the L allele of SREBP-1 showed higher fat content than animals carrying the S allele. These results suggest a possible use of these loci in gene-assisted selection programs for the improvement of milk quality traits and MCP in Brown Swiss cattle, although large scale studies in different breeds are required.

  3. Effects of Stearoyl-CoA Desaturase 1 and Sterol Regulatory Element Binding Protein Gene Polymorphisms on Milk Production, Composition and Coagulation Properties of Individual Milk of Brown Swiss Cows

    Directory of Open Access Journals (Sweden)

    Alice Maurmayr

    2011-09-01

    Full Text Available Associations between stearoyl-CoA desaturase (SCD and sterol regulatory element binding protein (SREBP-1 gene polymorphisms and milk production, composition (fat, protein, and casein content, acidity (pH and titratable acidity and coagulation properties (MCP, namely rennet coagulation time (RCT, min and curd firmness (a30, mm were investigated on individual Brown Swiss milk. A total of 294 cows from 16 herds and progeny of 15 sires were milk-sampled once. Th e additive effects of SCD and SREBP-1 genotypes on the aforementioned traits were analyzed through Bayesian linear models. The SCD gene was associated with protein content, casein content and a30. Lower protein, casein and a30 was observed for milk yielded by SCD V than A cows, whereas for other traits the effect was trivial. Animals carrying the L allele of SREBP-1 showed higher fat content than animals carrying the S allele. These results suggest a possible use of these loci in gene-assisted selection programs for the improvement of milk quality traits and MCP in Brown Swiss cattle, although large scale studies in different breeds are required.

  4. Effect of feeding buckwheat and chicory silages on fatty acid profile and cheese-making properties of milk from dairy cows.

    Science.gov (United States)

    Kälber, Tasja; Kreuzer, Michael; Leiber, Florian

    2013-02-01

    Fresh buckwheat (Fagopyrum esculentum) and chicory (Cichorium intybus) had been shown to have the potential to improve certain milk quality traits when fed as forages to dairy cows. However, the process of ensiling might alter these properties. In the present study, two silages, prepared from mixtures of buckwheat or chicory and ryegrass, were compared with pure ryegrass silage (Lolium multiflorum) by feeding to 3 × 6 late-lactating cows. The dietary dry matter proportions realised for buckwheat and chicory were 0.46 and 0.34 accounting also for 2 kg/d of concentrate. Data and samples were collected from days 10 to 15 of treatment feeding. Buckwheat silage was richest in condensed tannins. Proportions of polyunsaturated fatty acids (PUFA) and α-linoleic acid in total fatty acids (FA) were highest in the ryegrass silage. Feed intake, milk yield and milk gross composition did not differ among the groups. Feeding buckwheat resulted in the highest milk fat concentrations (g/kg) of linoleic acid (15.7) and total PUFA (40.5; both P silage shortened rennet coagulation time by 26% and tended (P silage seems to have a certain potential to modify the transfer of FA from feed to milk and to contribute to improved cheese-making properties.

  5. Properties of buffalo Mozzarella cheese as affected by type of coagulante

    Directory of Open Access Journals (Sweden)

    Nawal S. Ahmed

    2011-09-01

    Full Text Available   Background. Mozzarella is one of several pasta filata or stretched curd cheeses that originated in Italy. The name pasta filata refers to a unique plasticizing and texturing treatments of the fresh curd in hot water that imparts to the finished cheese its characteristic fibrous structure and melting properties. Mozzarella cheese made from standardized buffalo milk with 3 and 1.5% fat. The effect of coagulant types (calf rennet, chymosin and Mucor miehei rennet on the cheese properties was carried out. Material and methods. Fresh raw buffalo milk and starter cultures of Streptococcus salvarius ssp. thermophilus and Lactobacillus delbrueckii ssp. bulgaricus were used. The coagulants were calf rennet powder (HA-LA, microbial rennet powder (formase ISOTL from Mucor miehei and chymosin derived by fermentation (CDF. Milk, curd, whey,kneading water and cheese were analysed. The slab gel electrophoresis patterns of Mozzarella cheese were also applied. Statistical analyses were also applied on the obtained data. Results. Recovery of DM of both curd and cheese decreased in case of using Mucor miehei rennet while the recovery of TP and fat content in both curd and cheese and their loss to whey and kneading water were nearly the same. Soluble nitrogen and soluble tyrosine and tryptophan contents elevated with increasing the storage period. Increasing rate of the soluble nitrogen in case of using Mucor miehei rennet was higher compared to that made with the other types of coagulant. TVFA content increased with advancing the storage period, also increased with increasing the fat content of the original milk fat used. No effect can be seen due to the coagulant types. The meltability increased with storage period progress. While the effect of the type of coagulant enzyme hade neglect effect on meltability fat leakage and oiling off. Mozzarella cheese made with Mucor miehei rennet obtained the highest firmness compared with those made using calf rennet, or

  6. Chemical and functional properties of glycomacropeptide (GMP) and its role in the detection of cheese whey adulteration in milk: a review.

    Science.gov (United States)

    Neelima; Sharma, Rajan; Rajput, Yudhishthir Singh; Mann, Bimlesh

    2013-01-01

    Glycomacropeptide (GMP) is a C-terminal part (f 106-169) of kappa-casein which is released in whey during cheese making by the action of chymosin. GMP being a biologically active component has gained much attention in the past decade. It also has unique chemical and functional properties. Many of the biological properties have been ascribed to the carbohydrate moieties attached to the peptide. The unique set of amino acids in GMP makes it a sought-after ingredient with nutraceutical properties. Besides its biological activity, GMP has several interesting techno-functional properties such as wide pH range solubility, emulsifying properties as well as foaming abilities which are shown to be promising for applications in food and nutrition industry. These properties of GMP have given new dimension for the profitable utilization of cheese whey to the dairy industry. A number of protocols for isolation of GMP from cheese whey have been reported. Moreover, its role in detection of sweet/rennet whey adulteration in milk and milk products has also attracted attention of various researchers, and many GMP-specific analytical methods have been proposed. This review discusses the chemico-functional properties of GMP and its role in the detection methods for checking cheese or sweet whey adulteration in milk. Recent concepts used in the isolation of GMP from cheese whey have also been discussed.

  7. Influence of processing on functionality of milk and dairy proteins.

    Science.gov (United States)

    Augustin, Mary Ann; Udabage, Punsandani

    2007-01-01

    The inherent physical functionality of dairy ingredients makes them useful in a range of food applications. These functionalities include their solubility, water binding, viscosity, gelation, heat stability, renneting, foaming, and emulsifying properties. The suitability of dairy ingredients for an application can be further tailored by altering the structure of the proteins using appropriate processes. The processes discussed include physical modification (heat treatment, acidification, addition of mineral slats, homogenization, and shear), enzymatic modification (renneting, hydrolysis, and transglutamination), and chemical modification (use of chemical agents and the Maillard reaction). Emerging food processes (high pressure and ultrasound) are also discussed. The challenges for using dairy ingredients for the delivery of nutrients and bioactive components, while maintaining physical functionality, are also highlighted. There is a need for continued research into the fundamental aspects of milk proteins and their responses to various stresses for further differentiation of milk products and for the delivery of ingredients with consistent quality for target applications.

  8. Selection for milk coagulation properties predicted by Fourier transform infrared spectroscopy in the Italian Holstein-Friesian breed.

    Science.gov (United States)

    Chessa, S; Bulgari, O; Rizzi, R; Calamari, L; Bani, P; Biffani, S; Caroli, A M

    2014-07-01

    Milk coagulation is based on a series of physicochemical changes at the casein micelle level, resulting in formation of a gel. Milk coagulation properties (MCP) are relevant for cheese quality and yield, important factors for the dairy industry. They are also evaluated in herd bulk milk to reward or penalize producers of Protected Designation of Origin cheeses. The economic importance of improving MCP justifies the need to account for this trait in the selection process. A pilot study was carried out to determine the feasibility of including MCP in the selection schemes of the Italian Holstein. The MCP were predicted in 1,055 individual milk samples collected in 16 herds (66 ± 24 cows per herd) located in Brescia province (northeastern Italy) by means of Fourier transform infrared (FTIR) spectroscopy. The coefficient of determination of prediction models indicated moderate predictions for milk rennet coagulation time (RCT=0.65) and curd firmness (a₃₀=0.68), and poor predictions for curd-firming time (k₂₀=0.49), whereas the range error ratio (8.9, 6.9, and 9.5 for RCT, k₂₀, and a₃₀, respectively) indicated good practical utility of the predictive models for all parameters. Milk proteins were genotyped and casein haplotypes (αS₁-, β-, αS₂-, and κ-casein) were reconstructed. Data from 51 half-sib families (19.9 ± 16.4 daughters per sire) were analyzed by an animal model to estimate (1) the genetic parameters of predicted RCT, k₂₀, and a₃₀; (2) the breeding values for these predicted clotting variables; and (3) the effect of milk protein genotypes and casein haplotypes on predicted MCP (pMCP). This is the first study to estimate both genetic parameters and breeding values of pMCP, together with the effects of milk protein genotypes and casein haplotypes, that also considered k₂₀, probably the most important parameter for the dairy industry (because it indicates the time for the beginning of curd-cutting). Heritability of predicted

  9. Properties of fermented beverages from modified cow milk

    Directory of Open Access Journals (Sweden)

    Romualda Danków

    2013-12-01

    Full Text Available A characteristic property of mare milk is its low fat and protein content and high lactose content. Whey proteins account for approximately 40% total protein content, while casein content is below 50%. For this reason mare milk is defined as albumin milk in contrast to casein-type cow milk. The aim of the study was to modify cow milk composition to imitate that of mare milk using the microfiltration process. Fermented drinks were produced from modified cow milk with the use of two different starter cultures. Produced drinks were subjected to organoleptic examination, as well as physico-chemical and microbiological analyses. Analyses were performed after 1, 3, 7, 14 and 21 days of cold storage. It was found that active acidity, density, colour and dynamic viscosity changed during storage. Counts of lactic acid bacteria and yeasts decreased. Drinks differed in terms of their taste, as well as aroma and consistency.

  10. The nonlinear effect of somatic cell count on milk composition, coagulation properties, curd firmness modeling, cheese yield, and curd nutrient recovery.

    Science.gov (United States)

    Bobbo, T; Cipolat-Gotet, C; Bittante, G; Cecchinato, A

    2016-07-01

    The aim of this study was to investigate the relationships between somatic cell count (SCC) in milk and several milk technological traits at the individual cow level. In particular, we determined the effects of very low to very high SCC on traits related to (1) milk yield and composition; (2) coagulation properties, including the traditional milk coagulation properties (MCP) and the new curd firming model parameters; and (3) cheese yield and recovery of milk nutrients in the curd (or loss in the whey). Milk samples from 1,271 Brown Swiss cows from 85 herds were used. Nine coagulation traits were measured: 3 traditional MCP [rennet coagulation time (RCT, min), curd firming rate (k20, min), and curd firmness after 30 min (a30, mm)] and 6 new curd firming and syneresis traits [potential asymptotic curd firmness at infinite time (CFP, mm), curd firming instant rate constant (kCF, % × min(-1)), syneresis instant rate constant (kSR, % × min(-1)), rennet coagulation time estimated using the equation (RCTeq, min), maximum curd firmness achieved within 45 min (CFmax, mm), and time at achievement of CFmax (tmax, min)]. The observed cheese-making traits included 3 cheese yield traits (%CYCURD, %CYSOLIDS, and %CYWATER, which represented the weights of curd, total solids, and water, respectively, as a percentage of the weight of the processed milk) and 4 nutrient recoveries in the curd (RECFAT, RECPROTEIN, RECSOLIDS, and RECENERGY, which each represented the percentage ratio between the nutrient in the curd and milk). Data were analyzed using a linear mixed model with the fixed effects of days in milk, parity, and somatic cell score (SCS), and the random effect of herd-date. Somatic cell score had strong influences on casein number and lactose, and also affected pH; these were traits characterized by a quadratic pattern of the data. The results also showed a negative linear relationship between SCS and milk yield. Somatic cell score influenced almost all of the tested

  11. [Making tablets of powdered milk and the physical properties].

    Science.gov (United States)

    Shibata, Mitsuho; Otsubo, Kazumitsu; Nakane, Shota; Niwa, Toshiyuki; Danjo, Kazumi

    2011-01-01

    Compressed baby milk powder has proven to be very convenient for parents due to the ease with which it can be handled, and the fact that use of a measuring scoop is not necessary. The purpose of this study was to develop a compressed baby milk powder and analyze the resulting physical properties. The basic production process consisted of the following steps: 1) molding milk powder by low compression pressure, 2) humidification at 25°C·97%RH and 3) drying with use of a desiccant. No chemical additives were used for solidification; therefore the chemical composition of the compressed milk powder is identical to the base milk powder. The important properties of the compressed milk powder are both ready solubility and the strength of the solid. The compressed milk powder obtained at low pressure was too brittle for practical use, but the strength was increased by humidification followed by drying. During the humidification process, the powder particles located close to the surface of the compressed milk powder partially dissolve resulting in bridging structures between the particles, leading to an increase in strength. Both specific surface area and the volume ratio of the compressed milk powder decreased. Testing showed that caking between the particles occurred following humidification, and that the volume of caking affected the ease with which the compressed milk powder dissolves in water.

  12. A comparison of milk clotting characteristics and quality traits of Rendena and Holstein-Friesian cows

    Directory of Open Access Journals (Sweden)

    Alice Varotto

    2015-05-01

    Full Text Available Milk coagulation properties (MCP and composition, as predicted by mid-infrared spectroscopy (MIRS, were compared between Rendena (RE local breed and Holstein- Friesian (HF cows using 4614 individual milk samples from 28 single-breed herds. Records of rennet coagulation time (RCT, min, curd firmness (a30, mm, daily milk yield and quality traits were analysed using a linear mixed model which included fixed effects of breed, herd-test-date nested within breed, lactation stage, parity, and two-way interactions between the main effects. Random effects were cow nested within breed and residual. Milk from RE coagulated 2.1 min earlier and showed a firmer curd by 4.8 mm than that of HF cows (P<0.05. Milk yield (+9.7 kg/d and fat content (+0.22 g/100 g were greater for HF than RE (P<0.05, while protein (+0.05 g/100 g and casein (+0.06 g/100 g contents were greater in milk from RE cows (P<0.05. Rennet coagulation time was shortest at the beginning of lactation, and a30 was firmest at the beginning and end of lactation. Results from this study suggest that milk of RE is more suitable for cheese processing than that of HF cows. Milk clotting characteristics of the local breed should be taken into account when developing strategies useful for its valorisation.

  13. Importance of casein micelle size and milk composition for milk gelation.

    Science.gov (United States)

    Glantz, M; Devold, T G; Vegarud, G E; Lindmark Månsson, H; Stålhammar, H; Paulsson, M

    2010-04-01

    The economic output of the dairy industry is to a great extent dependent on the processing of milk into other milk-based products such as cheese. The yield and quality of cheese are dependent on both the composition and technological properties of milk. The objective of this study was to evaluate the importance and effects of casein (CN) micelle size and milk composition on milk gelation characteristics in order to evaluate the possibilities for enhancing gelation properties through breeding. Milk was collected on 4 sampling occasions at the farm level in winter and summer from dairy cows with high genetic merit, classified as elite dairy cows, of the Swedish Red and Swedish Holstein breeds. Comparisons were made with milk from a Swedish Red herd, a Swedish Holstein herd, and a Swedish dairy processor. Properties of CN micelles, such as their native and rennet-induced CN micelle size and their zeta-potential, were analyzed by photon correlation spectroscopy, and rennet-induced gelation characteristics, including gel strength, gelation time, and frequency sweeps, were determined. Milk parameters of the protein, lipid, and carbohydrate profiles as well as minerals were used to obtain correlations with native CN micelle size and gelation characteristics. Milk pH and protein, CN, and lactose contents were found to affect milk gelation. Smaller native CN micelles were shown to form stronger gels when poorly coagulating milk was excluded from the correlation analysis. In addition, milk pH correlated positively, whereas Mg and K correlated negatively with native CN micellar size. The milk from the elite dairy cows was shown to have good gelation characteristics. Furthermore, genetic progress in relation to CN micelle size was found for these cows as a correlated response to selection for the Swedish breeding objective if optimizing for milk gelation characteristics. The results indicate that selection for smaller native CN micelles and lower milk pH through breeding would

  14. The mechanism and properties of acid-coagulated milk gels

    Directory of Open Access Journals (Sweden)

    Chanokphat Phadungath

    2005-03-01

    Full Text Available Acid-coagulated milk products such as fresh acid-coagulated cheese varieties and yogurt areimportant dairy food products. However, little is known regarding the mechanisms involved in gel formation, physical properties of acid gels, and the effects of processing variables such as heat treatment and gelation temperature on the important physical properties of acid milk gels. This paper reviews the modern concepts of possible mechanisms involved in the formation of particle milk gel aggregation, along with recent developments including the use of techniques such as dynamic low amplitude oscillatory rheology to observe the gel formation process, and confocal laser scanning microscopy to monitor gel microstructure.

  15. Human milk bactericidal properties: effect of lyophilization and relation to maternal factors and milk components.

    Science.gov (United States)

    Salcedo, Jaime; Gormaz, Maria; López-Mendoza, Maria C; Nogarotto, Elisabetta; Silvestre, Dolores

    2015-04-01

    Lyophilization appears to be a viable method for storing human milk, assuring no microbiological contamination and preserving its health benefits and antibacterial properties. The aim of the study is to evaluate and compare the effects of different storage methods (lyophilization and freezing at -20°C and -80°C) and maternal factors (gestational length or time postpartum) upon the microbiological contents and bactericidal activity of human milk. The possible relation between bactericidal activity and the content of certain nutrients and functional components is also investigated. Microbiological content, bactericidal activity, sialic acid, and ganglioside contents, as well as protein, fat, and lactose concentrations were assessed in 125 human milk samples from 65 healthy donors in the Human Milk Bank of La Fe (Valencia, Spain). Lyophilization and storage at -80°C significantly reduced the content of mesophilic aerobic microorganisms and Staphylococcus epidermidis when compared with storage at -20°C. Bactericidal activity was not significantly modified by lyophilization when compared with freezing at either -20°C or -80°C. Bactericidal activity was not correlated with fat, protein, or lactose content, but was significantly correlated to ganglioside content. The bactericidal activity was significantly greater (P milk and in milk from women with term delivery than in milk from early lactation (days 1-7 postpartum) and milk from women with preterm delivery, respectively. Lyophilization and storage at -80°C of human milk yields similar results and are superior to storage at -20C with regard to microbial and bactericidal capacities, being a feasible alternative for human milk banks.

  16. Research progress of the calf rennet substitutes for cheese-making%干酪用牛凝乳酶替代品的研究进展

    Institute of Scientific and Technical Information of China (English)

    普燕; 张富春

    2015-01-01

    牛凝乳酶具有高凝乳活性和低非特异蛋白水解活性而广泛用于干酪制备.随着干酪市场的逐年增长,牛凝乳酶出现供不应求,其替代品应运而生,包括其他动物凝乳酶、植物凝乳酶、微生物凝乳酶、重组凝乳酶.在这些替代品中,重组牛凝乳酶显示出与天然牛凝乳酶相似的酶学特性,并且纯度更高,制作的干酪品质更好.目前已经有重组牛凝乳酶上市出售,成功替代了天然牛凝乳酶,但关于提高重组牛凝乳酶表达量与催化活性的研究远未止步.文中主要综述了凝乳酶结构、牛凝乳酶的替代品和重组凝乳酶的研究进展,详细综述了一些提高重组牛凝乳酶的表达方法,为外源蛋白在宿主中的高水平表达提供了有效参考.%Calf rennet is widely used in the process of cheese-making due to its high milk-clotting activity and low nonspecific proteolytic activity.As the cheese market increases in recent years,calf rennet supply falls short of demand and its substitutes are studied extensively,such as animal rennet,plant coagulant,microbial coagulant and recombinant chymosin.Among these substitutes,the recombinant bovine chymosin shows high similar enzymic properties to the natural calf rennet,and possesses high purity,thus the quality of the cheese made with it is better.Now the recombinant bovine chymosins have been listed for sale and the recombinant bovine chymosin have replaced the natural calf rennet successfully.But the studies on the improvement of expression quantity and catalytic activity of recombinant bovine chymosin never stop.In this paper,the research progress on the structure of chymosin,the calf rennet substitutes and the recombinant chymosin,and particularly the methods used to improve the expression quantity of the recombinant bovine chymosin is reviewed.These methods can offer certain reference for expression of foreign proteins at a high level in hosts.

  17. MILK COAGULATION PROPERTIES OF CATTLE BREEDS REARED IN ALPINE AREA

    Directory of Open Access Journals (Sweden)

    Giulio Visentin

    2015-09-01

    Full Text Available The aim of the present study was to apply mid-infrared spectroscopy prediction models developed for milk coagulation properties (MCP to a spectral dataset of 123,240 records collected over a 2-year period in the Alpine area, and to investigate sources of variation of the predicted MCP. Mixed linear models included fixed effects of breed, month and year of sampling, days in milk, parity, and the interactions between the main effects. Random effects were herd nested within breed, cow nested within breed, and the residual. All fixed effects were significant (P<0.05 in explaining the variation of MCP. In particular, milk clotting characteristics varied significantly among breeds, and local Alpine Grey breed exhibited the most favourable processing characteristics. Milk coagulation properties varied across lactation and were at their worst after the peak.

  18. Encapsulation of probiotic bacteria in lamb rennet paste: effects on the quality of Pecorino cheese.

    Science.gov (United States)

    Santillo, A; Albenzio, M; Bevilacqua, A; Corbo, M R; Sevi, A

    2012-07-01

    Lamb rennet pastes containing encapsulated Lactobacillus acidophilus and a mix of Bifidobacterium longum and Bifidobacterium lactis were produced for Pecorino cheese manufacture from Gentile di Puglia ewe milk. Cheeses were denoted as RP cheese when made with traditional rennet paste, RP-L cheese when made with rennet paste containing L. acidophilus culture, and RP-B cheese when made with rennet paste containing a mix of B. lactis and B. longum. Biochemical features of Pecorino cheese were studied at 1, 15, 30, 60, and 120 d of cheese ripening. The effect of encapsulation and bead addition to rennet acted on a different way on the viability of probiotic. Lactobacillus acidophilus retained its viability for 4 to 5 d and then showed a fast reduction; on the other hand, B. longum and B. lactis experienced kinetics characterized by an initial death slope, followed by a tail effect due to acquired resistance. At 1 d of ripening, the levels of L. acidophilus and bifidobacteria in cheese were the lowest, and then increased, reaching the highest levels after 30 d; such cell loads were maintained throughout the ripening for L. acidophilus, whereas bifidobacteria experienced a decrease of about 1 log cfu/g at the end of ripening. Enzymatic activities and biochemical features of cheeses were influenced by the type of rennet used for cheesemaking. Greater enzymatic activity was recorded in RP-L and RP-B cheese due to the presence of probiotic bacteria released from alginate beads. A positive correlation was found between enzymatic activities and water-soluble nitrogen and proteose-peptone in RP-B and RP-L cheeses; water-soluble nitrogen and proteose-peptone were the highest in RP-B. Principal component analysis distinguished RP-L from the other cheeses on the basis of the conjugated linoleic acid content, which was higher in the RP-L due to the ability of L. acidophilus to produce conjugated linoleic acid in the cheese matrix. Copyright © 2012 American Dairy Science

  19. Genetic and environmental relationships of different measures of individual cheese yield and curd nutrients recovery with coagulation properties of bovine milk.

    Science.gov (United States)

    Cecchinato, A; Bittante, G

    2016-03-01

    The aim of this study was to elucidate the relationships between various cheesemaking-related traits, namely the well-known traditional milk coagulation properties (MCP), the new curd firming and syneresis traits, the cheese yield, and the curd nutrient recoveries or whey losses (all measured at the individual level). Data were obtained from 1,167 Brown Swiss cows reared in 85 herds. A 2-L milk sample was collected once from each animal and assessed for 10 phenotypes related to changes in curd firmness (CF) over time, plus 7 cheesemaking traits. The CF-related traits included 4 traditional single-point lactodynamographic properties [rennet coagulation time (RCT, min); time to a CF of 20mm, min; and the CF 30 and 45 min after rennet addition (a30 and a45, respectively)], 4 parameters used to model the 360 CF data recorded over time for each milk sample [the potential asymptotic CF at infinite time (CFP, mm); the CF instant rate constant, % × min(-1); the syneresis instant rate constant, % × min(-1); and the RCT obtained from modeling individual samples], and 2 traits calculated from individual equations [the maximum CF(CFmax, mm); and the time at CFmax, min]. The cheesemaking traits included 3 cheese yield traits (weights of the fresh curd, curd solids and curd moisture as percent of the weights of the processed milk) and 4 milk nutrient recoveries in the curd (calculated as the percent ratios between a given nutrient in the curd versus that in the processed milk). Bayesian methodology-based multivariate analyses were used to estimate the phenotypic, additive genetic, herd/date, and residual relationships between the aforementioned traits, whereas statistical inferences were based on the marginal posterior distributions of the parameters of concern. The a45, CFP, and CFmax traits were genetically associated with all of the percent cheese yield traits (the additive genetic correlations varied from 0.752 to 0.855 for a45; 0.496 to 0.583 for CFP; and 0.750 to 0

  20. Pathway-based genome-wide association analysis of milk coagulation properties, curd firmness, cheese yield, and curd nutrient recovery in dairy cattle.

    Science.gov (United States)

    Dadousis, C; Pegolo, S; Rosa, G J M; Gianola, D; Bittante, G; Cecchinato, A

    2017-02-01

    It is becoming common to complement genome-wide association studies (GWAS) with gene-set enrichment analysis to deepen the understanding of the biological pathways affecting quantitative traits. Our objective was to conduct a gene ontology and pathway-based analysis to identify possible biological mechanisms involved in the regulation of bovine milk technological traits: coagulation properties, curd firmness modeling, individual cheese yield (CY), and milk nutrient recovery into the curd (REC) or whey loss traits. Results from 2 previous GWAS studies using 1,011 cows genotyped for 50k single nucleotide polymorphisms were used. Overall, the phenotypes analyzed consisted of 3 traditional milk coagulation property measures [RCT: rennet coagulation time defined as the time (min) from addition of enzyme to the beginning of coagulation; k20: the interval (min) from RCT to the time at which a curd firmness of 20 mm is attained; a30: a measure of the extent of curd firmness (mm) 30 min after coagulant addition], 6 curd firmness modeling traits [RCTeq: RCT estimated through the CF equation (min); CFP: potential asymptotic curd firmness (mm); kCF: curd-firming rate constant (% × min(-1)); kSR: syneresis rate constant (% × min(-1)); CFmax: maximum curd firmness (mm); and tmax: time to CFmax (min)], 3 individual CY-related traits expressing the weight of fresh curd (%CYCURD), curd solids (%CYSOLIDS), and curd moisture (%CYWATER) as a percentage of weight of milk processed and 4 milk nutrient and energy recoveries in the curd (RECFAT, RECPROTEIN, RECSOLIDS, and RECENERGY calculated as the % ratio between the nutrient in curd and the corresponding nutrient in processed milk), milk pH, and protein percentage. Each trait was analyzed separately. In total, 13,269 annotated genes were used in the analysis. The Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway databases were queried for enrichment analyses. Overall, 21 Gene Ontology and 17 Kyoto Encyclopedia of

  1. Calcium Impact on Milk Gels Formation

    DEFF Research Database (Denmark)

    Koutina, Glykeria

    to be formed. In addition the low amount of micellar calcium caused a more compact gel structure with many protein aggregates. The results of this study highlighted the importance of calcium for the formation of acid, calcium and rennet gels. The content and the interactions of calcium with proteins during...... salts. The perturbation of calcium equilibria by these factors will affect the final properties of acid, calcium and rennet milk gels. By decreasing the pH from 6.0 to 5.2 (acid gels), the calcium equilibrium was significantly affected by temperature (4, 20, 30, 40 oC), and different combinations...... of temperature and pH may result in different final structure properties in dairy products such as cheese. A significant amount of calcium remained in the micelles between pH 4.8 and 4.6, this can contribute to the final strength of acid milk gels, such as in yogurt or in cream cheeses. After the gelation point...

  2. [Breast milk: its nutritional composition and functional properties].

    Science.gov (United States)

    Tackoen, M

    2012-09-01

    Human milk is a complex biological fluid with thousands of components. The milk composition in the mammalian species is specific and adapted to the needs of the offspring. It contains macronutrients (proteins, lipids and carbohydrates), micronutrients (minerals and vitamins) and numerous biologically active substrates. Human milk not only covers the nutritional needs of the newborn but protects the baby against infection, inflammation and oxidative stress. It has immunomodulation properties and confers trophical protection to the intestinal mucosa. The newborn infant is particularly immature: innate immunity, adaptive immunity and intestinal immaturity. Human milk will offer this exogenous protective and immunomodulating source. The development of the composition of the intestinal microflora of the neonate will be impacted by pre- and probiotic components of human milk. Current scientific knowledge of human milk properties highlights interdependency of the different components, ontogeny of the intestinal function, development of the mucosal intestinal immune system, colonization by the intestinal microbiota and protection against pathogens. Quality of these interactions influences the newborn's short and long-term health status. The promotion of breastfeeding with the support of the Baby Friendly Hospital Initiative (BFHI) program and labeling has been shown to have positive impact in public health.

  3. Physicochemical properties of acidified skim milk gels containing cocoa flavanols.

    Science.gov (United States)

    Vega, César; Grover, Mollie K

    2011-06-22

    The physicochemical properties of acidified milk gels after the addition of cocoa flavanols were studied. As the flavanol level increased (from 0 to 2.5 mg/g), syneresis and gel elasticity (tan δ) were found to significantly increase and decrease, respectively. Flavanol addition reduced the stress at fracture, with no changes in fracture strain, suggesting that the bond type (i.e., covalent vs noncovalent) was the underlying factor explaining the ease of fracture. Gels made from recombined milks containing the casein fraction of heated milk and the serum of heated flavanol/milk mixtures showed the lowest values of G' and fracture stress. It was concluded that whey proteins/flavanol interactions were responsible for the poor mechanical properties of flavanol-added acidified milk gels. High-performance liquid chromatography analysis of milk sera showed that 60% of the total available monomeric flavanols was found in the serum phase from which 75% was non-associated to whey proteins. Concomitantly, >70% of flavanols with degree of polymerization >3 were found to be associated with the casein fraction.

  4. Effect of high hydrostatic pressure, ultrasound and pulsed electric fields on milk composition and characteristics

    Directory of Open Access Journals (Sweden)

    Irena Jeličić

    2012-03-01

    Full Text Available High hydrostatic pressure, ultrasonication and pulsed eletrcic fields (PEF belong to novel food processing methods which are mostly implemented in combination with moderate temperatures and/ or in combination with each other in order to provide adequate microbiological quality with minimal losses of nutritional value. All of three mentioned methods have been intensively investigated for the purpose of inactivation and reduction of foodborne microorganisms present in milk and dairy products. However, a large number of scientific researches have been dedicated to investigation of impact of these methods on changes in constituents like milk fat, milk proteins and lactose as well as changes in mechanisms like renneting properties and coagulation of milk. The aim of this research was to give an overview of changes in milk constituents induced by high hydrostatic pressure, ultrasonification and pulsed electric field treatments as well as to suggest how these changes could improve conventional processes in the dairy industry.

  5. The effects of over sea height of locality on some chemical, health, microbiological, physical and technological parameters of cow milk and sensorical properties of cheeses

    Directory of Open Access Journals (Sweden)

    Oto Hanuš

    2005-01-01

    Full Text Available In general, the over sea height is cumulative factor, which can influence significantly the farm conditions. This effect consists of temperature (mean year temperature, rain (sum of rainfulls, sunshine (total period of sunshine and so on, in terms of climate, which can influence the dairy cow keeping directly and indirectly. Direct effects can influence the welfare of dairy cows in terms of hot stress for example, which could decrease a mastitis resistance of cows or their milk yield in simply way. Indirect effects can influence the dairy cows and their milk production (milk yield and milk composition and quality by typical kinds of forages and preserved rough fodders, by their botany composition and nutritional quality. In general it is possible to say, that increasing over sea height decreases economical efficiency of dairying. On the other hand the higher over sea height is sometimes linked with pastoral system of dairy cow rearing and nourishment and more often with possibility to ecological and biodynamical agriculture application. In the fact, the mountain and submountain localities are named as less favourable areas (LFAs in terms of agriculture efficiency and sustainability under the Czech Republic conditions. Despite of above mentioned facts, the pastoral system of dairying plays very important role for tourism development in different countries such as Alpine or Scandinavien countries, Ireland, The Netherlands or in particular in New Zealand.It could be very good to know the incidentaly possible impacts of over sea height of dairy cow rearing localities on milk quality, composition and its technological properties because of discussions about incidental dairy subsidies. Of course, in some countries including the Czech Republic, the governmental production subsidies or governmental environmental subsidies are partly linked with over sea height of localities of dairy farms, according to different calculation formulas as well

  6. Functional and technological properties of camel milk proteins: a review

    DEFF Research Database (Denmark)

    Hailu, Yonas; Hansen, Egon Bech; Seifu, Eyassu

    2016-01-01

    processed in dairy plants, and a number of consumer products have been marketed. A better understanding of the technological and functional properties, as required for product improvement, has been gained in the past years. Absence of the whey protein β-LG and a low proportion of к-casein cause differences...... in relation to dairy processing. In addition to the technological properties, there are also implications for human nutrition and camel milk proteins are of interest for applications in infant foods, for food preservation and in functional foods. Proposed health benefits include inhibition of the angiotensin......This review summarises current knowledge on camel milk proteins, with focus on significant peculiarities in protein composition and molecular properties. Camel milk is traditionally consumed as a fresh or naturally fermented product. Within the last couple of years, an increasing quantity is being...

  7. Hydrolysis by Alcalase Improves Hypoallergenic Properties of Goat Milk Protein

    Science.gov (United States)

    Yun, Sung-Seob; Lee, Won-Jae; Kim, Jin-Wook; Ha, Ho-Kyung; Yoo, Michelle

    2016-01-01

    Goat milk is highly nutritious and is consumed in many countries, but the development of functional foods from goat milk has been slow compared to that for other types of milk. The aim of this study was to develop a goat milk protein hydrolysate (GMPH) with enhanced digestibility and better hypoallergenic properties in comparison with other protein sources such as ovalbumin and soy protein. Goat milk protein was digested with four commercial food-grade proteases (separately) under various conditions to achieve the best hydrolysis of αs -casein and β-lactoglobulin. It was shown that treatment with alcalase (0.4%, 60℃ for 30 min) effectively degraded these two proteins, as determined by SDS-PAGE, measurement of nonprotein nitrogen content, and reverse-phase high-performance liquid chromatography. Hydrolysis with alcalase resulted in a significant decrease in β-lactoglobulin concentration (almost to nil) and a ~40% reduction in the level of αs-casein. Quantification of histamine and TNF-α released from HMC-1 cells (human mast cell line) showed that the GMPH did not induce an allergic response when compared to the control. Hence, the GMPH may be useful for development of novel foods for infants, the elderly, and convalescent patients, to replace cow milk. PMID:27621693

  8. Hydrolysis by Alcalase Improves Hypoallergenic Properties of Goat Milk Protein.

    Science.gov (United States)

    Jung, Tae-Hwan; Yun, Sung-Seob; Lee, Won-Jae; Kim, Jin-Wook; Ha, Ho-Kyung; Yoo, Michelle; Hwang, Hyo-Jeong; Jeon, Woo-Min; Han, Kyoung-Sik

    2016-01-01

    Goat milk is highly nutritious and is consumed in many countries, but the development of functional foods from goat milk has been slow compared to that for other types of milk. The aim of this study was to develop a goat milk protein hydrolysate (GMPH) with enhanced digestibility and better hypoallergenic properties in comparison with other protein sources such as ovalbumin and soy protein. Goat milk protein was digested with four commercial food-grade proteases (separately) under various conditions to achieve the best hydrolysis of αs -casein and β-lactoglobulin. It was shown that treatment with alcalase (0.4%, 60℃ for 30 min) effectively degraded these two proteins, as determined by SDS-PAGE, measurement of nonprotein nitrogen content, and reverse-phase high-performance liquid chromatography. Hydrolysis with alcalase resulted in a significant decrease in β-lactoglobulin concentration (almost to nil) and a ~40% reduction in the level of αs-casein. Quantification of histamine and TNF-α released from HMC-1 cells (human mast cell line) showed that the GMPH did not induce an allergic response when compared to the control. Hence, the GMPH may be useful for development of novel foods for infants, the elderly, and convalescent patients, to replace cow milk.

  9. Physicochemical and acid gelation properties of commercial UHT-treated plant-based milk substitutes and lactose free bovine milk.

    Science.gov (United States)

    Mäkinen, Outi E; Uniacke-Lowe, Thérèse; O'Mahony, James A; Arendt, Elke K

    2015-02-01

    Physicochemical and acid gelation properties of UHT-treated commercial soy, oat, quinoa, rice and lactose-free bovine milks were studied. The separation profiles were determined using a LUMiSizer dispersion analyser. Soy, rice and quinoa milks formed both cream and sediment layers, while oat milk sedimented but did not cream. Bovine milk was very stable to separation while all plant milks separated at varying rates; rice and oat milks being the most unstable products. Particle sizes in plant-based milk substitutes, expressed as volume mean diameters (d4.3), ranged from 0.55μm (soy) to 2.08μm (quinoa) while the average size in bovine milk was 0.52μm. Particles of plant-based milk substitutes were significantly more polydisperse compared to those of bovine milk. Upon acidification with glucono-δ-lactone (GDL), bovine, soy and quinoa milks formed structured gels with maximum storage moduli of 262, 187 and 105Pa, respectively while oat and rice milks did not gel. In addition to soy products currently on the market, quinoa may have potential in dairy-type food applications. Copyright © 2014 Elsevier Ltd. All rights reserved.

  10. Quantification of bovine milk protein composition and coagulation properties using infrared spectroscopy and chemometrics: A result of collinearity among reference variables.

    Science.gov (United States)

    Eskildsen, C E; Skov, T; Hansen, M S; Larsen, L B; Poulsen, N A

    2016-10-01

    Predicting protein fractions and coagulation properties in bovine milk using Fourier transform infrared (FT-IR) measurements is desirable. However, such predictions may rely on correlations with total protein content. The aim of this study was to show how correlations between total protein content, protein fractions, and coagulation properties are responsible for the successful prediction of protein fractions and rennet-induced coagulation properties in milk samples. This study comprised 832 bovine milk samples from 2 breeds (426 Holstein and 406 Jersey). Holstein samples were collected from 20 Danish dairy herds from October to December 2009; Jersey samples were collected from 22 Danish dairy herds from February to April 2010. All samples were from conventional herds and taken while cows were housed. The results showed that κ-CN, αS1-CN, αS1-CN with 8 phosphorylated groups attached (αS1-CN 8P), and curd firming rate could be predicted from FT-IR measurements of the milk samples (with coefficients of determination between 0.66 and 0.71). However, the success of these FT-IR-based predictions was based on indirect relationships with total protein content. Hence, the FT-IR predictions relied on covariance structures with total protein content rather than absorption bands directly associated with the protein fractions and coagulation properties. If covariance structures between the protein fractions, coagulation properties, and total protein content used to calibrate partial least squares models were not conserved in future samples, these samples would show incorrect predictions of the protein fractions and coagulation properties. We demonstrated this using samples from 1 breed to calibrate and samples from the other breed to validate partial least squares models for β-CN. The 2 breeds had different covariance structures between β-CN and total protein content, and the validation samples yielded incorrect predictions. This finding may limit the usefulness of FT

  11. Functional and technological properties of camel milk proteins: a review.

    Science.gov (United States)

    Hailu, Yonas; Hansen, Egon Bech; Seifu, Eyassu; Eshetu, Mitiku; Ipsen, Richard; Kappeler, Stefan

    2016-11-01

    This review summarises current knowledge on camel milk proteins, with focus on significant peculiarities in protein composition and molecular properties. Camel milk is traditionally consumed as a fresh or naturally fermented product. Within the last couple of years, an increasing quantity is being processed in dairy plants, and a number of consumer products have been marketed. A better understanding of the technological and functional properties, as required for product improvement, has been gained in the past years. Absence of the whey protein β-LG and a low proportion of к-casein cause differences in relation to dairy processing. In addition to the technological properties, there are also implications for human nutrition and camel milk proteins are of interest for applications in infant foods, for food preservation and in functional foods. Proposed health benefits include inhibition of the angiotensin converting enzyme, antimicrobial and antioxidant properties as well as an antidiabetogenic effect. Detailed investigations on foaming, gelation and solubility as well as technological consequences of processing should be investigated further for the improvement of camel milk utilisation in the near future.

  12. KEFIRS MANUFACTURED FROM CAMEL (CAMELUS DRAMEDARIUS MILK AND COW MILK: COMPARISON OF SOME CHEMICAL AND MICROBIAL PROPERTIES

    Directory of Open Access Journals (Sweden)

    G. Kavas

    2015-09-01

    Full Text Available This study examined the production possibilities of kefir from fresh camel milk fermented with grain. The findings were then compared with kefir manufactured from cow’s milk. Cow’s milk was fermented with 2.5% grains. The 1% (v/w glucose enriched camel’s milk was fermented with 10% grains and left in an incubator at 25°C. Physical-chemical and sensorial analyses of the kefir sampleswere measured on day one (18 hours of storage and microbiological analyses were measured on days one, three and five. Some physical-chemical parameters were found to be higherin camel milk and its kefir than in cow milk and its kefir, some were found to be close and some were found to be lower. Addition of 1% glucose and 10% grains to the camel milk affected the titrationacidity and viscosity of kefir to significant levels. The kefir produced from camel milk was perceived as sourer, whereas its other properties were found to be close to those of cow milk. Thecholesterol levels of camel milk and its kefir were detected to be higher when compared to those of cow milk and its kefir, but the cholesterol level decreased in both examples after the productionof kefir. In terms of the composition of fatty acids, it was determined that SFA and the small, medium chain fatty acids ratio was low in camel milk and its kefir, but MUFA and the long chainfatty acids ratio was high. PUFA ratio was high in camel milk but low in its kefir. In microbiological analysis, yeast levels increased in kefir samples with the Lactobacillus ssp. strains, and theincrease in the number of yeasts was higher than in the cow milk kefir. In kefir samples, Lactobacillus ssp. strains increased on day one and three of storage, but diminished after day three.

  13. Mutagenesis by UV and Nitrous Acid for increase of rennet production in Rhizomucor miehei

    Directory of Open Access Journals (Sweden)

    Naser Tajik

    2014-07-01

    Full Text Available   Introduction : In this study, Mutation and Selection technique was used to increase production of Rennet (milk clotting enzyme in Rhizomucor miehei. Mutation and Selection is a technique for microbial strain improvement in which, mutation is induced on an organism by mutagen factors, then superior mutants are selected by screening procedures.   Materials and methods Mutations were induced by an optimized dose of UV (as physical mutagen and Nitrous acid (as chemical mutagen. Superior mutants were selected and compared to the parent strain regarding the clotting activity, proteolytic activity, enzyme production kinetic, yield, productivity and special growth rate in 5 replications.   Results : The milk clotting activity of parent strain was 1183 SU.mL-1. Mutants designated U-1113 and N-0227 were isolated which, produced 1771 and 1864 respectively. ratio was measured 4950, 8114 and 8193 SU.PU-1 in parent, U-1113 and N-0227, respectively.   Discussion and conclusion : Production of enzymes in mutants U-1113 and N-0227 were increased 49.7 and 57.6% respectively, relative to parent strain. Yield of production, productivity and C/P ratio were also increased significantly in mutants, regarding the same figures obtained for parent (p<0.05 that shows mutagens were used, have effected on quantity and quality of strain rennet.

  14. Ewe welfare and ovine milk and cheese quality

    Directory of Open Access Journals (Sweden)

    A. Sevi

    2010-04-01

    Full Text Available Causes of welfare reduction in dairy sheep flocks are presented and their impact on ovine milk and cheese quality is discussed. Attention is focused on climatic extremes, poor housing and milking hygiene, and nutritional imbalance: mechanisms are outlined through which stress-induced reduction of immune function can result in poor milk composition, deteriorated renneting ability of milk and altered proteolysis in cheese during ripening. In particular, the impact is brought out of exposure to high ambient temperature on the nutritional properties of ewe milk, in terms of increased short-chain and saturated fatty acids, and decreased unsaturated to saturated fatty acid ratio. As well, the relationship is highlighted between ewe welfare and udder health. Especially under poor hygiene conditions the risk of mastitis markedly increases due to reduction of the natural defense mechanisms of the teat and mammary gland and increased number and pathogenicity of the micro-organisms in contact with the entrance of the teat canal. Evidence is provided that rise in milk somatic cell count, in response to bacteria penetration into the udder, can lead to decreased milk yield and altered composition of milk and cheese, due to extensive epithelium secretory cell damage.

  15. Rheological, texture and sensory properties of kefir from mare’s milk and its mixtures with goat and sheep milk

    Directory of Open Access Journals (Sweden)

    Dorota Cais-Sokolińska

    2016-11-01

    Full Text Available The aim of this study was to conduct lactic acid-alcoholic fermentation using mesophilic lactic acid bacteria (LAB for mare’s milk and its mixture with goat and sheep milk, followed by instrumental and sensory characteristic of the texture profile in the produced kefirs. It was shown that kefirs made from a mixture of goat and sheep milk are firmer, have greater values of consistency and the viscosity index than those produced from mare’s milk alone. Kefir storage for 3 weeks causes changes in their mechanical properties. Exceptions are found for firmness of kefirs made from both mixtures and the viscosity index of kefir made from sheep milk, which remained stable. The most divergent texture profile of the tested kefirs was reflected in the sensory examined descriptors of prickling, dense and mouth-coating sensation.

  16. Freezing Point of Milk: A Natural Way to Understand Colligative Properties

    Science.gov (United States)

    Novo, Mercedes; Reija, Belen; Al-Soufi, Wajih

    2007-01-01

    A laboratory experiment is presented in which the freezing point depression is analyzed using milk as solution. The nature of milk as a mixture of different solutes makes it a suitable probe to learn about colligative properties. The first part of the experiment illustrates the analytical use of freezing point measurements to control milk quality,…

  17. Short communication: Flavor and flavor stability of cheese, rennet, and acid wheys.

    Science.gov (United States)

    Smith, S; Smith, T J; Drake, M A

    2016-05-01

    Dried whey ingredients are valuable food ingredients but potential whey sources are underutilized. Previous work has established flavor and flavor stability differences in Cheddar and Mozzarella wheys, but little work has compared these whey sources to acid or rennet wheys. The objective of this study was to characterize and compare flavor and flavor stability among cheese, rennet, and acid wheys. Full-fat and fat-free Cheddar, rennet and acid casein, cottage cheese, and Greek yogurt fluid wheys were manufactured in triplicate. Wheys were fat separated and pasteurized followed by compositional analyses and storage at 4°C for 48 h. Volatile compound analysis and descriptive sensory analysis were evaluated on all liquid wheys initially and after 24 and 48 h. Greek yogurt whey contained almost no true protein nitrogen (0.02% wt/vol) whereas other wheys contained 0.58%±0.4% (wt/vol) true protein nitrogen. Solids and fat content were not different between wheys, with the exception of Greek yogurt whey, which was also lower in solids content than the other wheys (5.6 vs. 6.5% wt/vol, respectively). Fresh wheys displayed sweet aromatic and cooked milk flavors. Cheddar wheys were distinguished by diacetyl/buttery flavors, and acid wheys (acid casein, cottage cheese, and Greek yogurt) by sour aromatic flavor. Acid casein whey had a distinct soapy flavor, and acid and Greek yogurt wheys had distinct potato flavor. Both cultured acid wheys contained acetaldehyde flavor. Cardboard flavor increased and sweet aromatic and buttery flavors decreased with storage in all wheys. Volatile compound profiles were also distinct among wheys and changed with storage, consistent with sensory results. Lipid oxidation aldehydes increased in all wheys with storage time. Fat-free Cheddar was more stable than full-fat Cheddar over 48h of storage. Uncultured rennet casein whey was the most stable whey, as exhibited by the lowest increase in lipid oxidation products over time. These results

  18. Milk protein tailoring to improve functional and biological properties

    Directory of Open Access Journals (Sweden)

    JEAN-MARC CHOBERT

    2012-01-01

    Full Text Available Proteins are involved in every aspects of life: structure, motion, catalysis, recognition and regulation. Today's highly sophisticated science of the modifications of proteins has ancient roots. The tailoring of proteins for food and medical uses precedes the beginning of what is called biochemistry. Chemical modification of proteins was pursued early in the twentieth century as an analytical procedure for side-chain amino acids. Later, methods were developed for specific inactivation of biologically active proteins and titration of their essential groups. Enzymatic modifications were mainly developed in the seventies when many more enzymes became economically available. Protein engineering has become a valuable tool for creating or improving proteins for practical use and has provided new insights into protein structure and function. The actual and potential use of milk proteins as food ingredients has been a popular topic for research over the past 40 years. With today's sophisticated analytical, biochemical and biological research tools, the presence of compounds with biological activity has been demonstrated. Improvements in separation techniques and enzyme technology have enabled efficient and economic isolation and modification of milk proteins, which has made possible their use as functional foods, dietary supplements, nutraceuticals and medical foods. In this review, some chemical and enzymatic modifications of milk proteins are described, with particular focus on their functional and biological properties.

  19. FERMENTABILITY AND RHEOLOGICAL PROPERTIES OF LACTOPEROXIDASE ACTIVATED BUFFALO MILK YOGHURT

    Directory of Open Access Journals (Sweden)

    Aijaz H. Soomro

    2012-12-01

    Full Text Available Present study was planned to produce and evaluate the coagulum from buffalo milk preserved with the activation of its lactoperoxidase system (LPO-system. A total of 10 trials were conducted and in each trial milk base was equally divided into three parts, two of which were treated with 20 mg/L (A and 30 mg/L (B solution of Sodium thiocyanate + Hydrogen peroxide and third part was kept as control (C. All the samples were analyzed for fermentability trend, pH, acidity, viscosity, specific gravity, syneresis and organoleptic properties. The decreasing trend in pH during fermentation period was comparatively slow in LPO-system activated milk A and B (4h and 5h as compared to control yoghurt (3h. The titratable acidity (% lactic acid of A, B and C yoghurt was 0.86±0.022, 0.85±0.025 and 0.89±0.024, respectively. The viscosity and specific gravity of control yoghurt was significantly (P0.05 were observed in the total solids, fat, ash, lactose and protein contents among the control, A and B yoghurt. Two week stored samples of control yoghurt received lower sensory score for appearance, flavor, body/texture and overall acceptability as compared to fresh control yoghurt. Simultaneously, LPO-system treated A and B yoghurt received high score during storage period than the control yoghurt.

  20. Contributions to ultrasound monitoring of the process of milk curdling.

    Science.gov (United States)

    Jiménez, Antonio; Rufo, Montaña; Paniagua, Jesús M; Crespo, Abel T; Guerrero, M Patricia; Riballo, M José

    2017-04-01

    Ultrasound evaluation permits the state of milk being curdled to be determined quickly and cheaply, thus satisfying the demands faced by today's dairy product producers. This paper describes the non-invasive ultrasonic method of in situ monitoring the changing physical properties of milk during the renneting process. The basic objectives of the study were, on the one hand, to confirm the usefulness of conventional non-destructive ultrasonic testing (time-of-flight and attenuation of the ultrasound waves) in monitoring the process in the case of ewe's milk, and, on the other, to include other ultrasound parameters which have not previously been considered in studies on this topic, in particular, parameters provided by the Fast Fourier Transform technique. The experimental study was carried out in a dairy industry environment on four 52-l samples of raw milk in which were immersed 500kHz ultrasound transducers. Other physicochemical parameters of the raw milk (pH, dry matter, protein, Gerber fat test, and lactose) were measured, as also were the pH and temperature of the curdled samples simultaneously with the ultrasound tests. Another contribution of this study is the linear correlation analysis of the aforementioned ultrasound parameters and the physicochemical properties of the curdled milk.

  1. [Therapeutic properties of proteins and peptides from colostrum and milk].

    Science.gov (United States)

    Zimecki, Michał; Artym, Jolanta

    2005-01-01

    Colostrum and milk are rich in proteins and peptides which play a crucial role in innate immunity when transferred to the offspring and may accelerate maturation of the immune system in neonates. The immunotropic properties of these proteins prompted investigators research their potential application in prevention and therapy. Lactoferrin (LF) exhibits antibacterial, antifungal, antiviral, antiparasitice, and antitumoral activities. It is protective with regard to intestinal epithelium, promotes bone growth, and accelerates the recovery of immune system function in immunocompromised animals. LF was tried in the treatment of hepatitis C infection and the intestinal form of graft-versus-host disease (GvHD). A proline-rich polypeptide (PRP) demonstrated a variety of immunotropic functions, including the promotion of T-cell maturation and inhibition of autoimmune disorders. PRP, in the form of chewable tablets (Colostrinin) was recently found to improve or stabilize the health status of Alzheimer's disease patients. Casein and casein-derived peptides showed protective activities in enamel demineralization and as caries-preventing agents. The protein hydrolyzates were also protective in diabetic animals, reduced tumor growth, had antihypertensive activity and diminished colicky symptoms in infants. Glycomacropeptide (GMP), a peptide derived from kappa-casein, exhibited various antibacterial and antithrombotic activities. Alpha-lactalbumin (LA) demonstrated antiviral, antitumoral and anti-stress properties. LA-enriched diets were anxiolytic, lowered blood pressure in rats, prevented diarrhea, and led to a better weight gain in malnourished children. HAMLET, a complex of LA and oleic acid, was effective in patients with cutaneous papillomas. Lysozyme found application in infant formulas, the treatment of periodentitis, and the prevention of tooth decay. Milk enriched in lysozyme was used in feeding premature infants suffering from concomitant diseases. Interesting

  2. Genetic parameters for milk coagulation properties in Estonian Holstein cows.

    NARCIS (Netherlands)

    Vallas, M.; Bovenhuis, H.; Kaart, T.; Parna, K.; Kiiman, H.

    2010-01-01

    The objective of this study was to estimate heritabilities and repeatabilities for milk coagulation traits [milk coagulation time (RCT) and curd firmness (E30)] and genetic and phenotypic correlations between milk yield and composition traits (milk fat percentage and protein percentage, urea, somati

  3. Use of artichoke (Cynara scolymus) flower extract as a substitute for bovine rennet in the manufacture of Gouda-type cheese: characterization of aspartic proteases.

    Science.gov (United States)

    Llorente, Berta E; Obregón, Walter David; Avilés, Francesc X; Caffini, Néstor O; Vairo-Cavalli, Sandra

    2014-09-15

    Artichoke (Cynara scolymus L.) flower extract was assayed with the aim of replacing animal rennet in the manufacture of Gouda-type cheeses from bovine milk. Floral extract coagulated milk within a suitable time for use on an industrial scale, while the yield of cheese obtained was equal to that achieved with bovine abomasum. Five proteolytic fractions with milk-clotting activity were isolated in a two-step purification protocol, three belonging to the cardosin group. Cheeses made with C. scolymus proteases must be brined for a longer period (40 h) to prevent overproteolysis and avoid the development of a background flavor. The type of coagulant (bovine or vegetable) had no significant effect on the cheeses' chemical parameters analyzed throughout ripening, and no significant organoleptic differences were detected between those manufactured with C. scolymus or animal rennet. The results indicate that C. scolymus flower extract is suitable for replacing animal rennet in the production of Gouda-type cheeses. Copyright © 2014 Elsevier Ltd. All rights reserved.

  4. Physical properties of pizza Mozzarella cheese manufactured under different cheese-making conditions.

    Science.gov (United States)

    Banville, V; Morin, P; Pouliot, Y; Britten, M

    2013-08-01

    The effect of manufacturing factors on the shreddability and meltability of pizza Mozzarella cheese was studied. Four experimental cheeses were produced with 2 concentrations of denatured whey protein added to milk (0 or 0.25%) and 2 renneting pH values (6.4 or 6.5). The cheeses were aged 8, 22, or 36d before testing. Shreddability was assessed by the presence of fines, size of the shreds, and adhesion to the blade after shredding at 4, 13, or 22°C. A semi-empirical method was developed to measure the matting behavior of shreds by simulating industrial bulk packaging. Rheological measurements were performed on cheeses with and without a premelting treatment to assess melt and postmelt cheese physical properties. Lowering the pH of milk at renneting and aging the cheeses generally decreased the fines production during shredding. Adding whey protein to the cheeses also altered the fines production, but the effect varied depending on the renneting and aging conditions. The shred size distribution, adhesion to the blade, and matting behavior of the cheeses were adversely affected by increased temperature at shredding. The melting profiles obtained by rheological measurements showed that better meltability can be achieved by lowering the pH of milk at renneting or aging the cheese. The premelted cheeses were found to be softer at low temperatures (50°C) compared with the cheeses that had not undergone the premelting treatment. Understanding and controlling milk standardization, curd acidification, and cheese aging are essential for the production of Mozzarella cheese with desirable shreddability and meltability.

  5. The “maturation” of milk for Parmigiano- Reggiano cheesemaking: effects on mineral equilibria and technological properties

    OpenAIRE

    Mariani, P; Vecchia, P; A. Tambini; Pecorari, M; Franceschi, P.; A. Summer; M. Malacarne; Formaggioni, P.

    2010-01-01

    The “maturation” of milk for Parmigiano-Reggiano cheese is characterised by natural creaming process: the full cream milk is placed in large flat vats, for about 10-12 hours, to obtain the gravity separation of milk fat. The modifications of mineral equilibria and technological properties of milk during the “maturation” phase, were studied. To this aim 24 full cream (FC) milk samples and the corresponding partially skimmed (PS) milk, by natural creaming, were analysed....

  6. Ewe welfare and ovine milk and cheese quality

    OpenAIRE

    A. Sevi

    2010-01-01

    Causes of welfare reduction in dairy sheep flocks are presented and their impact on ovine milk and cheese quality is discussed. Attention is focused on climatic extremes, poor housing and milking hygiene, and nutritional imbalance: mechanisms are outlined through which stress-induced reduction of immune function can result in poor milk composition, deteriorated renneting ability of milk and altered proteolysis in cheese during ripening. In particular, the impact is brought out of exposure to ...

  7. Detection of cow milk adulteration in yak milk by ELISA.

    Science.gov (United States)

    Ren, Q R; Zhang, H; Guo, H Y; Jiang, L; Tian, M; Ren, F Z

    2014-10-01

    In the current study, a simple, sensitive, and specific ELISA assay using a high-affinity anti-bovine β-casein monoclonal antibody was developed for the rapid detection of cow milk in adulterated yak milk. The developed ELISA was highly specific and could be applied to detect bovine β-casein (10-8,000 μg/mL) and cow milk (1:1,300 to 1:2 dilution) in yak milk. Cross-reactivity was detection limit was 1% (vol/vol) cow milk in yak milk. Different treatments, including heating, acidification, and rennet addition, did not interfere with the assay. Moreover, the results were highly reproducible (coefficient of variation detected no significant differences between known and estimated values. Therefore, this assay is appropriate for the routine analysis of yak milk adulterated with cow milk.

  8. 热处理影响牛乳蛋白凝胶特性的研究进展%Research progress of heat treatment on gel property of milk protein

    Institute of Scientific and Technical Information of China (English)

    王伟军; 张兰威; 李延华; 张莉丽

    2011-01-01

    热处理是各种乳制品生产过程中不可或缺的工艺手段,热处理过程中乳体系的蛋白质会发生变化,影响制品的凝胶特性.介绍了牛乳酸凝胶的模型和酶凝胶的形成阶段,分析了加热过程中蛋白质可能发生的变化,简要阐述了热处理对凝乳效果的影响,指出热诱乳蛋白聚合物与凝乳的机制密切相关,旨在为乳制品加工中热处理的潜在影响提供理论参考.%Heat treatment is an indispensable processing step in the production of dairy products. Proteins changed when milk is heated, which can influence gel properties of milk protein. The model of acid gels and formation process of rennet gels were introduced in this paper. Changes in the proteins during heat treatments were analyzed. The clotting effects of heat treatment on milk were discussed. Based on these results, the conclusion that protein aggregates derived from heat treatments were closely related to mechanism of milk curds was pointed out. The results of the present paper can provide a theoretical reference for potential impacts of heat treatment in dairy products processing.

  9. The occurrence of noncoagulating milk and the association of bovine milk coagulation properties with genetic variants of the caseins in 3 Scandinavian dairy breeds

    DEFF Research Database (Denmark)

    Poulsen, Nina Aagaard; Bertelsen, Henriette Pasgaard; Jensen, Hanne Bak

    2013-01-01

    Substantial variation in milk coagulation properties has been observed among dairy cows. Consequently, raw milk from individual cows and breeds exhibits distinct coagulation capacities that potentially affect the technological properties and milk processing into cheese. This variation is largely...... breeds, which more or less reflected the single gene results. Overall, our results strongly suggest that milk coagulation is under the influence of additive genetic variation. Optimal milk for future cheese production can be ensured by monitoring the frequency of unfavorable variants and thus preventing...... an increase in the number of cows producing milk with impaired coagulation. Selective breeding for variants associated with superior milk coagulation can potentially increase raw milk quality and cheese yield in all 3 Scandinavian breeds...

  10. Effect of sucrose on physical properties of spray-dried whole milk powder.

    Science.gov (United States)

    Ma, U V Lay; Ziegler, G R; Floros, J D

    2008-11-01

    Spray-dried whole milk powders were prepared from whole condensed milk with various sucrose concentrations (0%, 2.5%, 5%, 7.5%, and 10% w/w), and their glass transition temperature and some physical properties of importance in chocolate manufacture were evaluated. In milk powder samples, the glass transition temperature and free-fat content decreased in a nonlinear manner with sucrose addition. Moreover, increasing sucrose concentration reduced the formation of dents on the particle surface. Addition of sucrose in whole condensed milk increased linearly the apparent particle density and in a nonlinear manner the particle size of spray-dried milk powders. The particle size volume distribution of milk powders with the highest sucrose concentration differed from the log-normal distribution of the other samples due to the formation of large agglomerates. Neither vacuole volume, nor the amorphous state of milk powders was affected by sucrose addition.

  11. Nutritional and therapeutic properties of goat’s milk

    Directory of Open Access Journals (Sweden)

    Zrinka Filipović Dermit

    2014-11-01

    Full Text Available Production of goat milk and its consumption in the world is increasing, and so is the population of goats which increases more than the population of other dairy animals. This is particularly true in countries where goat milk is reflection of the traditional production. Goat’s milk, in addition to the high nutritional value (better digestibility, hypoallergenic, higher buffering capacity, higher pH value is characterized by therapeutic characteristics important for human health. The preference of goat’s milk over cow’s milk is also a higher selenium content, which is essential for the activity of the enzyme glutathione peroxidase, also significant in the prevention of cancer and cardiovascular diseases. Goat’s milk in comparison with cow’s, contains more fatty acids, which have beneficial effects on human health, especially the cardiovascular system. Goat’s milk proteins are more digestible than cow’s milk proteins, also an absorption of amino acids are more efficient. The sensitivity of people to α-lactalbumin and β-lactoglobulin of cow’s milk is negligible after replacing cow’s milk with goat’s milk. The objective of this paper is to specify benefits of goat’s milk in regard to cow’s and highlight its therapeutic and nutritional values.

  12. Evaluation of camel milk for selected processing related parameters and comparisons with cow and buffalo milk

    Directory of Open Access Journals (Sweden)

    Shyam P. Sagar

    2016-12-01

    Full Text Available Cow and buffalo milk and camel milk were analyzed and compared for processing related parameters. The average heat stability of cow, buffalo and camel milk samples analyzed was 1807.4 seconds, 1574.6 seconds and 133.6 seconds respectively at 140 °C. Thus, the heat stability of camel milk was significantly lower than the cow milk and buffalo milk. The average rennet coagulation time (RCT of cow, buffalo and camel milk was 310.6 seconds, 257.4 seconds and 604.2 seconds respectively. Thus, RCT of camel milk was significantly higher than the cow milk and buffalo milk. The camel, cow and buffalo milk samples showed negative alcohol stability. The rate of acidity was increased propositionally with time in camel milk with no curd formation and weaker body.

  13. Physicochemical Properties and Antioxidant Activity of Milk Samples Collected from Five Goat Breeds in Malaysia

    Directory of Open Access Journals (Sweden)

    Saif Alyaqoubi

    2015-02-01

    Full Text Available Five different goat breeds (Saanen, Kacang, Jamnapari, Boer and a crossbred of Jamnapari and Saanen were obtained from one farm in Bandar Baru Bangi. The aim of this study was to determine the physicochemical properties and antioxidant capacity based on TPC, FRAP and DPPH. Goat milk samples were collected during the same lactation period (middle lactation and were subsequently compared with cow milk. The results of the study showed that goat milk exhibited a significantly higher (p<0.05 antioxidant capacity than cow milk. Jamnapari milk exhibited the highest antioxidant capacity in Total Phenol Content (TPC, Ferric Reducing Antioxidant Power (FRAP and 2,2-diphenyl-1-picrylhydrazyl (DPPH assays with values of 544.08 mg GA/100 g FW, 481.69 mg TE/100 g FW and 67.44%, respectively. By contrast, the milk samples obtained from the Boer exhibited the lowest corresponding values of 460.00 mg GA/100 g FW, 386.06 mg TE/100 g FW and 59.68%, respectively. Results showed that physicochemical properties were significantly different (p<0.05 among the milk samples, with some samples more superior compared with others in one or more aspects. Jamnapari milk was superior in terms of ash, total soluble solid and protein with values of 0.96%, 13.02 Brix and 5.11%, respectively and this milk also showed the lowest moisture (81.28% among all milk samples. Cow milk exhibited the highest fat (4.43% and Kacang milk had the lowest titratable acidity (0.06% than the other milk samples. Thus, goat milk can be considered as an excellence source of antioxidants.

  14. PEMANFAATAN MILK CLOTTING ENZYME DARI Lactobacillus casei D11 UNTUK PEMBUATAN KEJU MOZZARELLA [Utilization of Milk Clotting Enzyme from Lactobacillus casei D11 for Mozzarella Cheese Making

    Directory of Open Access Journals (Sweden)

    Rohmatussolihat -

    2015-07-01

    Full Text Available Milk Clotting Enzyme (MCE is an active agent for cheese making which may be produced by Lactic acid bacteria (LAB. MCE activity differs according to the LAB strains used. Lactobacillus casei D11 could produced MCE when it is grown in MRS broth medium. In this study, MCE of L. casei D11 with the addition of rennet is used and optimized for the production of mozzarella cheese using Response Surface Method (RSM with Central Composite Design (CCD. The organoleptic properties were determined by hedonics test involving 30 respondents and analyzed statistically which was followed by a Duncan's test. Furthermore, a proximate analysis of mozzarella cheese was conducted. Our results show that the MCE activity produced by L. casei D11 was 8.471 Soxhlet Unit with protease activity of 3.28 U/mL. The ANOVA results showed that the concentration of MCE significantly influence the production of curd. Theoptimum concentration of MCE and rennet for the production of curd suited for the production of mozzarella cheese were 20 and 0.002%, respectively, with a maximum predicted curd yield of 14.996% (g/100 mL milk which is increased by 13.9% as compared to the curd yield before optimization. The statistical analysis on taste, color, flavor, and cheese texture by respondents shows that mozzarella cheese made by a combination of 15% of MCE and 0.00079 and 0.0015% of rennet, were organoleptically superior to the commercial mozzarella used in this experiment. The proximate analysis shows that mozzarella produced has a moisture content of 33.34%(w/w, 3.48% ash, 30.44% fat, 25.12% protein, 7.53% carbohydrate and energy of 404 kkal/100g.

  15. Ultra-high pressure homogenization-induced changes in skim milk: impact on acid coagulation properties.

    Science.gov (United States)

    Serra, Mar; Trujillo, Antonio J; Jaramillo, Pamela D; Guamis, Buenaventura; Ferragut, Victoria

    2008-02-01

    The effects of ultra-high pressure homogenization (UHPH) on skim milk yogurt making properties were investigated. UHPH-treated milk was compared with conventionally homogenised (15 MPa) heat-treated skim milk (90 degrees C for 90 s), and to skim milk treated under the same thermal conditions but fortified with 3% skim milk powder. Results of the present study showed that UHPH is capable of reducing skim milk particle size which leads to the formation of finer dispersions than those obtained by conventional homogenisation combined with heat treatment. In addition, results involving coagulation properties and yogurt characteristics reflected that, when increasing UHPH pressure conditions some parameters such as density of the gel, aggregation rate and water retention are improved.

  16. Cheesemaking in highland pastures: Milk technological properties, cream, cheese and ricotta yields, milk nutrients recovery, and products composition.

    Science.gov (United States)

    Bergamaschi, M; Cipolat-Gotet, C; Stocco, G; Valorz, C; Bazzoli, I; Sturaro, E; Ramanzin, M; Bittante, G

    2016-12-01

    (before and after natural creaming), the whole morning milk, and the mixed vat milk had different chemical compositions, traditional coagulation properties, and curd-firming modeling parameters. These variations over the pasture season were similar to the residual variations with respect to chemical composition, and much lower with respect to coagulation and curd-firming traits. Much larger variations were noted in cream, cheese, and ricotta yields, as well as in nutrient recoveries in curd during the pasture season. The protein content of forage was correlated with some of the coagulation and curd-firming traits, the ether extract of forage was positively correlated with milk fat content and cheese yields, and fiber fractions of forage were unfavorably correlated with some of the chemical and technological traits. Traditional cheese- and ricotta-making procedures showed average cream, cheese, and ricotta yields of 6.3, 14.2, and 4.9%, respectively, and an overall recovery of almost 100% of milk fat, 88% of milk protein, and 60% of total milk solids.

  17. Effects of the amount of soy milk on thermorheological, thermal and textural properties of chocolate with soy milk

    Directory of Open Access Journals (Sweden)

    Zarić Danica B.

    2015-01-01

    Full Text Available Chocolate is a two-phase rheological system. The solid phase, consisting of non-fat cocoa particles, sugar and soy milk is wrapped in a fat phase - cocoa butter. Physical, thermal, textural and organoleptic properties of chocolate depend on the composition of the ingredients, manufacturing process and a properly conducted pre-crystallization phase. For this study, two chocolate masses were produced in a ball mill: one with 15% of soy milk powder (R1 and the other with 20% of soy milk powder (R2. The chocolate mass was produced at different milling times (30, 60 and 90 min, and pre-crystallization temperature (26, 28 and 30oC. The aim of the study was to evaluate the changes caused by different amounts of soy milk powder on the quality of the chocolate. The quality of chocolate was evaluated by comparing the nutritional composition, hardness, thermorheological and thermal properties of the chocolate mass. The results show that chocolate mass R2, due to the presence of higher amounts of soy milk proteins, should be milled longer, and also needs lower temperatures for pre-crystallization. [Projekat Ministarstva nauke Republike Srbije, br. TR 31014

  18. Effect of boiling on the antidiabetic property of enzyme treated sheep milk casein

    OpenAIRE

    Farhath Jan; Santosh Kumar; Richa Jha

    2016-01-01

    Aim: Sheep milk-born bioactive peptides have been found to exhibit various physiological activities. The present work was designed with the aim to evaluate the effect of boiling on antidiabetic property of peptides derived from sheep milk caseinate on hydrolysis with three different proteases. Materials and Methods: In this investigation, casein prepared from raw and boiled sheep milk was hydrolyzed by three commercially available proteases (trypsin, pepsin, and chymotrypsin). These hydrol...

  19. Physical and processing properties of milk, butter, and cheddar cheese from cows fed supplemental fish meal.

    Science.gov (United States)

    Avramis, C A; Wang, H; McBride, B W; Wright, T C; Hill, A R

    2003-08-01

    Physical, chemical, sensory and processing properties of milk produced by feeding a rumen-undegradable fish meal protein supplement to Holstein cows were investigated. The supplement contained (as fed basis) 25% soft-white wheat, 60% herring meal, and 15% feather meal. The total fat level in the milk decreased to 2.43%. For both pasteurized and ultra-high temperature processed drinking milk, no difference was found between fish meal (FM) milk and control milk in terms of color, flavor and flavor stability; in particular, no oxidized flavor was observed. Cheddar cheese made from FM milk ripened faster after 3 mo of ripening and developed a more desirable texture and stronger Cheddar flavor. The yield efficiencies for FM and control cheese, 94.4 (+/- 2.44 SE) and 96.4 (+/- 2.26 SE), respectively, were not different. Relative to controls, average fat globule size was smaller in FM milk and churning time of FM cream was longer. FM butter had softer texture and better cold spreadability, and butter oils from FM enriched milk had lower dropping points compared to control butter oil (average 32.89 versus 34.06 degrees C). These differences in physical properties of butter fat were greater than expected considering that iodine values were not different. This study demonstrates the feasibility of producing high quality products from milk naturally supplemented with FM, but the results also show that dietary changes affect processing properties.

  20. RELATIONS BETWEEN SELECTED INDICATORS OF BLOOD AND MILK OF DAIRY COWS WITH METABOLIC DISORDERS

    Directory of Open Access Journals (Sweden)

    Jaroslav Kováčik

    2013-02-01

    Full Text Available The aim of this work was to monitor the relations between selected indicators of technological properties of milk and blood biochemical parameters of dairy cows with metabolic disorders. Thirty-two cows were chosen, which were divided into 3 groups: first group - cows with metabolic problems of acidosis, second group - cows with metabolic problems of alkalosis, third group - healthy cows. Blood, urine and milk samples were collected. Urea, total lipids, total proteins, glucose and calcium was determined in the blood serum. Pure acidobasic forms, pH and density of urine were determined. Proteins, lactose, non-fat-solids, somatic cells count, calcium, urea, titratable acidity, fermentability, rennetability and thermostability were determined in samples of milk. Significant negative dependences were observed in the group of cows with metabolic problems of acidosis between urea in blood and in milk (r = -0.694, P <0.05, between calcium in blood and in milk (r = -0.653, P <0, 05, and between calcium in milk and glucose in blood (r = -0.648, P <0.05. In the group of cows with alkalosis, statistically significant correlation between total lipids in blood and fat in milk was found (r = -0.879, P <0.05.

  1. Effect of pulsed electric field on the rheological and colour properties of soy milk.

    Science.gov (United States)

    Xiang, Bob Y; Simpson, Marian V; Ngadi, Michael O; Simpson, Benjamin K

    2011-12-01

    The effects of pulsed electric field (PEF) treatments on rheological and colour properties of soy milk were evaluated. Flow behaviour, viscosity and rheological parameters of PEF-treated soy milk were monitored using a controlled stress rheometer. For PEF treatments, electric field intensity of 18, 20 and 22 kV cm(-1) and number of pulses of 25, 50, 75 and 100 were used. For the measurements of rheological properties of soy milk shear rates between 0 and 200 s(-1) was used. The rheological behaviour of control and the PEF-treated soy milk were described using a power law model. The PEF treatments affected the rheological properties of soy milk. Apparent viscosity of soy milk increased from 6.62 to 7.46 (10(-3) Pa s) with increase in electric field intensity from 18 to 22 kV cm(-1) and increase in the number of pulses from 0 to 100. The consistency index (K) of soy milk also changed with PEF treatments. Lightness (L*), red/greenness (a*) and yellowness/blueness (b*) of soy milk were affected by PEF treatments.

  2. Contribution of macrophages to plasmin activity in ewe bulk milk

    OpenAIRE

    Albenzio, M; A. Sevi; A. Marzano; Marino, R; Schena, L.; Caroprese , M

    2010-01-01

    A total of 225 bulk sheep milk samples were collected throughout lactation to assess the contribution of macrophages to the regulation of the plasmin/plasminogen system. Samples were analyzed for composition, milk renneting parameters, and for activities of plasmin (PL), plasminogen (PG) and plasminogen activators (PA). Isolation of macrophages from milk was performed using a magnetic positive separation; separated cells were lysed and activity of urokinase-PA was determined. PL activity in m...

  3. Dairy Technology : Principles of Milk. Properties and Processes

    NARCIS (Netherlands)

    Walstra, P.; Geurts, T.J.; Noomen, A.; Jellema, A.; Boekel, van M.A.J.S.

    1999-01-01

    This book covers the chemistry, physics, and microbiology of milk; the main unit operations applied in the manufacture of milk products; and procedures to ensure consumer safety, product quality, and efficient processing. The final section is devoted to describing the processes and interactions uniq

  4. Effect of total proteose-peptone content on the variability of bovine milk foaming property

    Directory of Open Access Journals (Sweden)

    Arianna Buccioni

    2013-02-01

    Full Text Available Several authors demonstrated a strong linkage between proteose-peptones content and foaming properties of cow milk; this is of great interest for Italian dairy industries to create a new line of fresh milk characterized by a particular foaming property and, hence, particularly appreciate in catering industry. The aim of this trial was to quantify the relation between total concentration of proteose-peptones and the entity of foaming attitude in cow fresh milk. Ninety samples of raw bulk milk were analysed for proteose-peptones content, plasmin activity, fatty acid profile and foaming attitude. A negative relation was found among proteose-peptones percentage and foaming attitude which decreased with the increase of plasmin activity and somatic cell content in milk.

  5. 微小毛霉凝乳酶干酪素的制备及应用性能研究%Optimization of Process Parameters for the Preparation of Rennet Casein

    Institute of Scientific and Technical Information of China (English)

    郑恒光; 陈君琛; 汤葆莎; 吴俐

    2011-01-01

    Rennet casein is a major raw material for making processed cheese. The research of its industrialization is still at preliminary stage in China. In this paper, its process parameters and application performance was studied. Rennet casein was prepared from the fresh skim milk with coagulant of self-prepared Mucor Pusilius rennet by the procedure of skimming, pasteurization, clotting, cooking, whey separation, washing, drying, milling and sieving. The results indicated that although the yield of rennet casein was not significantly affected by the dosage of rennet, pH of milk and cooking temperature, its functionality of melt ability, free oil, stretch ability, and oil binding capacity et al. Was significantly affected by different cooking temperature. The optimized process parameters for the preparation of rennet casein is dosage of milk 1U · mL-1, clotting pH 6. 6 and cooking temperature 60℃. Under this condition, the yield of rennet casein was 2.1A.%以新鲜牛奶为原料,采用自制微小毛霉Mucor Pusilius凝乳酶作为脱脂牛奶凝固剂,经过离心脱脂、巴氏杀菌、凝乳、热烫、离心脱乳清、水洗、干燥、粉碎过筛等步骤获得凝乳酶干酪素,考察工艺参数对干酪素得率及应用性能的影响.实验结果表明,凝乳酶添加量、凝乳pH值、热烫温度对凝乳酶干酪素得率无显著影响,热烫温度对产品的融化性、析油性、拉伸性、吸油性等应用性能有显著的影响.理想的凝乳酶干酪素制备条件:凝乳酶添加量1 U·mL-1牛奶,凝乳pH值6.6,热烫温度60℃,在此条件下,凝乳酶干酪素得率为2.1%.

  6. Effect of artisanal rennet paste on the chemical, sensory and microbiological characteristics of traditional goat's cheese

    Directory of Open Access Journals (Sweden)

    C. Tripaldi

    2015-12-01

    Full Text Available In a study using three replicates, Marzolina goat cheese made with artisanal rennet paste from goat kid was compared with cheese made with commercial liquid rennet from calf. Samples of fresh cheese were subjected to chemical and microbiological analyses. Samples of ripened cheese collected after 50 days of ripening were submitted to chemical and sensory analysis. Results of this study show that cheese made with artisanal rennet pastes did not contain pathogenic microorganisms and that this kind of rennet provided the enzymatic content necessary to achieve the typical characteristics of traditional cheeses.

  7. Changes in the physical properties, solubility, and heat stability of milk protein concentrates prepared from partially acidified milk.

    Science.gov (United States)

    Eshpari, H; Tong, P S; Corredig, M

    2014-12-01

    A limiting factor in using milk protein concentrates (MPC) as a high-quality protein source for different food applications is their poor reconstitutability. Solubilization of colloidal calcium phosphate (CCP) from casein micelles during membrane filtration (e.g., through acidification) may affect the structural organization of these protein particles and consequently the rehydration and functional properties of the resulting MPC powder. The main objective of this study was to investigate the effects of acidification of milk by glucono-δ-lactone (GDL) before ultrafiltration (UF) on the composition, physical properties, solubility, and thermal stability (after reconstitution) of MPC powders. The MPC samples were manufactured in duplicate, either by UF (65% protein, MPC65) or by UF followed by diafiltration (80% protein, MPC80), using pasteurized skim milk, at either the native milk pH (~pH 6.6) or at pH 6.0 after addition of GDL, followed by spray drying. Samples of different treatments were reconstituted at 5% (wt/wt) protein to compare their solubility and thermal stability. Powders were tested in duplicate for basic composition, calcium content, reconstitutability, particle size, particle density, and microstructure. Acidification of milk did not have any significant effect on the proximate composition, particle size, particle density, or surface morphology of the MPC powders; however, the total calcium content of MPC80 decreased significantly with acidification (from 1.84 ± 0.03 to 1.59 ± 0.03 g/100 g of powder). Calcium-depleted MPC80 powders were also more soluble than the control powders. Diafiltered dispersions were significantly less heat stable (at 120°C) than UF samples when dissolved at 5% solids. The present work contributes to a better understanding of the differences in MPC commonly observed during processing.

  8. Genetic parameters for milk coagulation properties in Estonian Holstein cows.

    Science.gov (United States)

    Vallas, M; Bovenhuis, H; Kaart, T; Pärna, K; Kiiman, H; Pärna, E

    2010-08-01

    The objective of this study was to estimate heritabilities and repeatabilities for milk coagulation traits [milk coagulation time (RCT) and curd firmness (E(30))] and genetic and phenotypic correlations between milk yield and composition traits (milk fat percentage and protein percentage, urea, somatic cell count, pH) in first-lactation Estonian Holstein dairy cattle. A total of 17,577 test-day records from 4,191 Estonian Holstein cows in 73 herds across the country were collected during routine milk recordings. Measurements of RCT and E(30) determined with the Optigraph (Ysebaert, Frepillon, France) are based on an optical signal in the near-infrared region. The cows had at least 3 measurements taken during the period from April 2005 to January 2009. Data were analyzed using a repeatability animal model. There was substantial variation in milk coagulation traits with a coefficient of variation of 27% for E(30) and 9% for the log-transformed RCT. The percentage of variation explained by herd was 3% for E(30) and 4% for RCT, suggesting that milk coagulation traits are not strongly affected by herd conditions (e.g., feeding). Heritability was 0.28 for RCT and 0.41 for E(30), and repeatability estimates were 0.45 and 0.50, respectively. Genetic correlation between both milk coagulation traits was negligible, suggesting that RCT and E(30) have genetically different foundations. Milk coagulation time had a moderately high positive genetic (0.69) and phenotypic (0.61) correlation with milk pH indicating that a high pH is related to a less favorable RCT. Curd firmness had a moderate positive genetic (0.48) and phenotypic (0.45) correlation with the protein percentage. Therefore, a high protein percentage is associated with favorable curd firmness. All reported genetic parameters were statistically significantly different from zero. Additional univariate random regression analysis for milk coagulation traits yielded slightly higher average heritabilities of 0.38 and 0

  9. Development of parmesan cheese production from local cow milk

    Science.gov (United States)

    Aliwarga, Lienda; Christianti, Elisabeth Novi; Lazarus, Chrisella

    2017-05-01

    Parmesan cheese is one of the dairy products which is used in various foods, such as pasta, bakery product, and pizza. It has a hard texture due to aging process for at least two years. Long aging period inhibited the production of parmesan cheese while consumer demands were increasing gradually. This research was conducted to figure out the effect of starter culture and rennet dose to the production of parmesan cheese. This research consists of (1) pasteurization of 1,500 ml milk at 73°C; and (2) main cheese making process that comprised of fermentation process and the addition of rennet. In latter stage, milk was converted into curd. Variations were made for the dose of bacteria culture and rennet. Both variables correlated to the fermentation time and characteristics of the produced cheese. The analysis of the produced cheese during testing stage included measured protein and cheese yield, whey pH, water activity, and moisture content. Moreover, an organoleptic test was done in a qualitative manner. The results showed that the dose of bacteria culture has a significant effect to the fermentation time, protein yield, and cheese yield. Meanwhile, rennet dose significantly affected cheese yield, pH of whey, and water activity. The highest protein yield (93.1%) was obtained at 0.6 ml of culture and 0.5 ml of rennet while the maximum cheese yield (6.81%) was achieved at 0.4 ml of culture and 0.1 ml of rennet. The water activity of produced cheeses was lower compared to the water activity of common parmesan cheese (ca. 0.6). For the organoleptic test, 0.4 ml of bacterial culture and 0.5 ml of rennet produced the most preferred cheese flavor compared to other variations.

  10. The eff ect of addition of selected milk protein preparations on the growth of Lactobacillus acidophilus and physicochemical properties of fermented milk

    Directory of Open Access Journals (Sweden)

    Waldemar Gustaw

    2016-03-01

    Full Text Available Background. The intake of fermented milk products, especially yoghurts, has been systematically increasing for a few decades. The purpose of this work was to obtain milk products fermented with a mix of bacterial cultures (yoghurt bacteria and Lactobacillus acidophillus LA-5 and enriched with selected milk protein preparations. Secondly, the aim of the work was to determine physiochemical and rheological properties of the obtained products. Material and methods. The following additives were applied in the experiment: whey protein concen- trate (WPC 65, whey protein isolate (WPI, demineralised whey powder (SPD, caseinoglycomacropeptide (CGMP, α-lactalbumin (α-la, sodium caseinate (KNa and calcium caseinate (KCa. Milk was fermented using probiotic strain Lactobacillus acidophillus LA-5 and a typical yoghurt culture. The products were analysed in terms of the survivability of bacterial cells during refrigerated storage, rheological properties and syneresis. Fermented milk products were obtained using blends of bacterial strains: ST-B01:Lb-12 (1:1, ST-B01:Lb-12:LA-5 (1:1:2. Results. Milk beverages fermented with typical yoghurt bacteria and LA-5 strain showed intensive syner- esis. The addition of LA-5 strain caused formation of harder acid gels, comparing to typical yoghurts. Milk products which were prepared from skimmed milk possessed higher values of hardness and consistency coefficient. The increase of concentrations of milk preparations (except of WPI did not cause significant differences in the hardness of acidic gels obtained by fermentation of mixed culture with a probiotic strain. Conclusion. The applied preparations improved physiochemical properties of the milk beverages which were prepared with a probiotic strain. The increase of protein milk preparations concentration resulted in a gradual decrease of the secreted whey. Among the products that were made of full milk powder and were subjected to three weeks of refrigerated storage

  11. Determination of free amino acids in whole-fat Turkish White Brined Cheese produced by animal and microbial milk-clotting enzymes with and without the addition of starter culture

    OpenAIRE

    Ufuk Eren-Vapur; Tulay Ozcan

    2012-01-01

    Coagulating enzymes are essential ingredients for the production of different cheese varieties. The objective of this research was to summarize the effect of rennet type (calf rennet and microbial rennet from Rhizomucor miehei) and starter culture on the sensory properties and free amino acids (FAA) release during the ripening of Turkish White brined cheese. The concentrations of FAA and sensory properties were similar for cheeses made with both types of coagulant and starter culture. Aminoac...

  12. Derivation of multivariate indices of milk composition, coagulation properties, and individual cheese yield in dairy sheep.

    Science.gov (United States)

    Manca, M G; Serdino, J; Gaspa, G; Urgeghe, P; Ibba, I; Contu, M; Fresi, P; Macciotta, N P P

    2016-06-01

    Milk composition and its technological properties are traits of interest for the dairy sheep industry because almost all milk produced is processed into cheese. However, several variables define milk technological properties and a complex correlation pattern exists among them. In the present work, we measured milk composition, coagulation properties, and individual cheese yields in a sample of 991 Sarda breed ewes in 47 flocks. The work aimed to study the correlation pattern among measured variables and to obtain new synthetic indicators of milk composition and cheese-making properties. Multivariate factor analysis was carried out on individual measures of milk coagulation parameters; cheese yield; fat, protein, and lactose percentages; somatic cell score; casein percentage; NaCl content; pH; and freezing point. Four factors that were able to explain about 76% of the original variance were extracted. They were clearly interpretable: the first was associated with composition and cheese yield, the second with udder health status, the third with coagulation, and the fourth with curd characteristics. Factor scores were then analyzed by using a mixed linear model that included the fixed effect of parity, lambing month, and lactation stage, and the random effect of flock-test date. The patterns of factor scores along lactation stages were coherent with their technical meaning. A relevant effect of flock-test date was detected, especially on the 2 factors related to milk coagulation properties. Results of the present study suggest the existence of a simpler latent structure that regulates relationships between variables defining milk composition and coagulation properties in sheep. Heritability estimates for the 4 extracted factors were from low to moderate, suggesting potential use of these new variables as breeding goals.

  13. Flavor and stability of milk proteins.

    Science.gov (United States)

    Smith, T J; Campbell, R E; Jo, Y; Drake, M A

    2016-06-01

    A greater understanding of the nature and source of dried milk protein ingredient flavor(s) is required to characterize flavor stability and identify the sources of flavors. The objective of this study was to characterize the flavor and flavor chemistry of milk protein concentrates (MPC 70, 80, 85), isolates (MPI), acid and rennet caseins, and micellar casein concentrate (MCC) and to determine the effect of storage on flavor and functionality of milk protein concentrates using instrumental and sensory techniques. Spray-dried milk protein ingredients (MPC, MPI, caseins, MCC) were collected in duplicate from 5 commercial suppliers or manufactured at North Carolina State University. Powders were rehydrated and evaluated in duplicate by descriptive sensory analysis. Volatile compounds were extracted by solid phase microextraction followed by gas chromatography-mass spectrometry (GC-MS) and gas chromatography-olfactometry. Compounds were identified by comparison of retention indices, odor properties, and mass spectra against reference standards. A subset of samples was selected for further analysis using direct solvent extraction with solvent-assisted flavor extraction, and aroma extract dilution analysis. External standard curves were created to quantify select volatile compounds. Pilot plant manufactured MPC were stored at 3, 25, and 40°C (44% relative humidity). Solubility, furosine, sensory properties, and volatile compound analyses were performed at 0, 1, 3, 6, and 12 mo. Milk proteins and caseins were diverse in flavor and exhibited sweet aromatic and cooked/milky flavors as well as cardboard, brothy, tortilla, soapy, and fatty flavors. Key aroma active compounds in milk proteins and caseins were 2-aminoacetophenone, nonanal, 1-octen-3-one, dimethyl trisulfide, 2-acetyl-1-pyrroline, heptanal, methional, 1-hexen-3-one, hexanal, dimethyl disulfide, butanoic acid, and acetic acid. Stored milk proteins developed animal and burnt sugar flavors over time. Solubility of

  14. Visible and near-infrared bulk optical properties of raw milk.

    Science.gov (United States)

    Aernouts, B; Van Beers, R; Watté, R; Huybrechts, T; Lammertyn, J; Saeys, W

    2015-10-01

    The implementation of optical sensor technology to monitor the milk quality on dairy farms and milk processing plants would support the early detection of altering production processes. Basic visible and near-infrared spectroscopy is already widely used to measure the composition of agricultural and food products. However, to obtain maximal performance, the design of such optical sensors should be optimized with regard to the optical properties of the samples to be measured. Therefore, the aim of this study was to determine the visible and near-infrared bulk absorption coefficient, bulk scattering coefficient, and scattering anisotropy spectra for a diverse set of raw milk samples originating from individual cow milkings, representing the milk variability present on dairy farms. Accordingly, this database of bulk optical properties can be used in future simulation studies to efficiently optimize and validate the design of an optical milk quality sensor. In a next step of the current study, the relation between the obtained bulk optical properties and milk quality properties was analyzed in detail. The bulk absorption coefficient spectra were found to mainly contain information on the water, fat, and casein content, whereas the bulk scattering coefficient spectra were found to be primarily influenced by the quantity and the size of the fat globules. Moreover, a strong positive correlation (r ≥ 0.975) was found between the fat content in raw milk and the measured bulk scattering coefficients in the 1,300 to 1,400 nm wavelength range. Relative to the bulk scattering coefficient, the variability on the scattering anisotropy factor was found to be limited. This is because the milk scattering anisotropy is nearly independent of the fat globule and casein micelle quantity, while it is mainly determined by the size of the fat globules. As this study shows high correlations between the sample's bulk optical properties and the milk composition and fat globule size, a

  15. Antimutagenic properties of lactic acid-cultured milk on chemical and fecal mutagens

    Energy Technology Data Exchange (ETDEWEB)

    Hosono, A.; Kashina, T.; Kada, T.

    1986-09-01

    The antimutagenic properties of milk cultured with Lactobacillus bulgaricus and Streptococcus thermophilus were examined using streptomycin-dependent strains of Salmonella in an in vitro assay system. The mutagens utilized for testing included 2-(2-furyl)-3-(5-nitro-2-furyl) acrylamide, 4-nitroquinoline-N-oxide, and fecal mutagenic extracts from cats, monkeys, dogs and other mammals. Both types of cultured milk exhibited antimutagenic activity on all mutagens used. Antimutagenic activities of the cultured milks with 2-(2-furyl)-3-(5-nitro-2-furyl) acrylamide and 4-nitroquinoline-N-oxide increased with incubation time but were thermolabile beyond 55/sup 0/C for 10 min.

  16. Study of Lactic Acid Bacteria Community From Raw Milk of Iranian One Humped Camel and Evaluation of Their Probiotic Properties

    OpenAIRE

    Davati, Nafiseh; Tabatabaee Yazdi, Farideh; Zibaee, Saeed; Shahidi, Fakhri; Edalatian, Mohammad Reza

    2015-01-01

    Background: Camel milk is amongst valuable food sources in Iran. On the other hand, due to the presence of probiotic bacteria and bacteriocin producers in camel milk, probiotic bacteria can be isolated and identified from this food product. Objectives: The objectives of the present research were the isolation and molecular identification of lactic acid bacteria from camel milk and evaluation of their probiotic properties. Materials and Methods: A total of ten samples of camel milk were collec...

  17. 21 CFR 184.1685 - Rennet (animal-derived) and chymosin preparation (fermentation-derived).

    Science.gov (United States)

    2010-04-01

    ... (fermentation-derived). 184.1685 Section 184.1685 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF... (animal-derived) and chymosin preparation (fermentation-derived). (a)(1) Rennet and bovine rennet are... clear solution containing the active enzyme chymosin (E.C. 3.4.23.4). It is derived, via fermentation...

  18. Proteolytic effect of Cynara cardunculus rennet for use in the elaboration of 'Torta del Casar' cheese.

    Science.gov (United States)

    Ordiales, Elena; Benito, Maria José; Martin, Alberto; Fernández, Margarita; Hernández, Alejandro; de Guia Córdoba, Maria

    2013-11-01

    The purpose of this work was to analyse the influence of rennet from different Cynara cardunculus plants, selected for its clotting and proteolytic activity on caseins, on the characteristics of manufactured 'Torta del Casar' cheeses. After classifying the cardoon according to proteolytic activity into five groups of greater or lesser activity, 16 batches of cheeses were made with rennet derived from different wild cardoon plants. We observed a major development of the proteolysis during ripening leading to the generation of non-protein nitrogen compounds. Especially noteworthy was the relationship of amino acid nitrogen (AN) generation with rennet clotting activity after 24 h of maceration, and the fact that the production of biogenic amines was not related to the proteolytic activity of the rennet. The activities of the rennet observed 'in vitro' were also developed 'in vivo' in the cheeses, with the different rennets used affecting the final sensory characteristics of cheeses. The rennet with high clotting activity after 24 h of maceration was positively correlated with the creaminess, viscosity, and acceptability of the cheese. However, the high proteolytic activity rennet negatively influenced the acidity, bitterness, and creaminess parameters. Therefore the most appropriate cardoons for making this cheese are those with higher clotting activities and moderate proteolytic activities especially on β-casein. The use of controlled and characterised cardoons in the manufacturing process of Torta del Casar is fundamental to obtaining the homogeneous product demanded by the Torta del Casar Registry of the Protected Designation of Origin.

  19. Eff ect of homogenization on the properties and microstructure of Mozzarella cheese from buff alo milk

    OpenAIRE

    S. Abd El-Rafee; M.M. El-Abd; Nawal S. Ahmed; Mona A.M. Abd El-Gawad

    2012-01-01

    Background. The name pasta fi lata refers to a unique plasticizing and texturing treatments of the fresh curd in hot water that imparts to the fi nished cheese its characteristic fi brous structure and melting properties. Mozzarella cheese made from standardized homogenized and non-homogenized buffalo milk with 3 and 1.5%fat. The effect of homogenization on rheological, microstructure and sensory evaluation was carried out. Material and methods. Fresh raw buffalo milk and starter cultures of ...

  20. Effect of boiling on the antidiabetic property of enzyme treated sheep milk casein

    Directory of Open Access Journals (Sweden)

    Farhath Jan

    2016-10-01

    Full Text Available Aim: Sheep milk-born bioactive peptides have been found to exhibit various physiological activities. The present work was designed with the aim to evaluate the effect of boiling on antidiabetic property of peptides derived from sheep milk caseinate on hydrolysis with three different proteases. Materials and Methods: In this investigation, casein prepared from raw and boiled sheep milk was hydrolyzed by three commercially available proteases (trypsin, pepsin, and chymotrypsin. These hydrolysates collected at different hydrolysis times (60, 120, 160, and 240 min were assayed for their antidiabetic activity. Results: Among the three different enzyme hydrolysates, casein treated with chymotrypsin shows the highest antidiabetic activity among other enzymes. While the antidiabetic effect of raw milk-derived casein hydrolysates always exceeds than effect shown by boiled milk casein hydrolysates. Conclusion: The result obtained hence shows that the effect of boiling on the properties of bioactive peptides released during different enzyme digestion depends largely on the enzymatic formulation used and treatment conditions. Chymotrypsin treatment of raw casein yields peptides with maximum antidiabetic activity as compared to pepsin and trypsin. Moreover, the peptides produced after enzymatic treatment of boiled casein show reduced antidiabetic properties. Therefore, enzymatically treated raw milk casein hydrolysates may be used as effective nutritional supplements for diabetic patients, as it causes a significant inhibition of α-amylase activity.

  1. Linear relationship between increasing amounts of extruded linseed in dairy cow diet and milk fatty acid composition and butter properties.

    Science.gov (United States)

    Hurtaud, C; Faucon, F; Couvreur, S; Peyraud, J-L

    2010-04-01

    The aim of this experiment was to compare the effects of increasing amounts of extruded linseed in dairy cow diet on milk fat yield, milk fatty acid (FA) composition, milk fat globule size, and butter properties. Thirty-six Prim'Holstein cows at 104 d in milk were sorted into 3 groups by milk production and milk fat globule size. Three diets were assigned: a total mixed ration (control) consisting of corn silage (70%) and concentrate (30%), or a supplemented ration based on the control ration but where part of the concentrate energy was replaced on a dry matter basis by 2.1% (LIN1) or 4.3% (LIN2) extruded linseed. The increased amounts of extruded linseed linearly decreased milk fat content and milk fat globule size and linearly increased the percentage of milk unsaturated FA, specifically alpha-linolenic acid and trans FA. Extruded linseed had no significant effect on butter color or on the sensory properties of butters, with only butter texture in the mouth improved. The LIN2 treatment induced a net improvement of milk nutritional properties but also created problems with transforming the cream into butter. The butters obtained were highly spreadable and melt-in-the-mouth, with no pronounced deficiency in taste. The LIN1 treatment appeared to offer a good tradeoff of improved milk FA profile and little effect on butter-making while still offering butters with improved functional properties.

  2. Influence of using a blend of rennet casein and whey protein concentrate as protein source on the quality of Mozzarella cheese analogue.

    Science.gov (United States)

    Dhanraj, Padhiyar; Jana, Atanu; Modha, Hiral; Aparnathi, K D

    2017-03-01

    The effect of incorporating whey protein concentrate (WPC) on the quality characteristics of Mozzarella cheese analogue (MCA) based on rennet casein (RC) was studied. The proportion of RC:WPC tried out were 95:5, 90:10, and 85:15 w/w. The formulation of MCA comprised of 23.5% of blend of RC and WPC, 15% specialty vegetable fat, 2.75% trisodium citrate + disodium hydrogen orthophosphate (2.5:1, w/w), 0.07% calcium chloride, 0.6% citric acid, 1.1% NaCl, 1.5% cheese bud flavoring, and rest water. Varying the proportion of RC and WPC had a significant influence on the composition, textural properties, baking qualities and sensory quality of MCA judged as a topping on pizza pie. MCA made using protein blends (RC:WPC-90:10 or 85:15) behaved satisfactorily during pizza baking trials. However, looking at the superiority of MCA made using RC:WPC (90:10) with regard to shred quality and marginal superiority in terms of the total sensory score of cheese, judged as pizza topping, the former blend (i.e. RC:WPC, 90:10) was selected. The MCA obtained employing such protein blend had composition similar to that of Pizza cheese prepared from cheese milk and had requisite baking characteristics needed as a pizza topping. It is recommended to use a blend of RC and WPC (90:10) as the protein source in the formulation of MCA to obtain nutritionally superior cheese product having desired functional properties for its end use in baking applications.

  3. Quality traits and modeling of coagulation, curd firming, and syneresis of sheep milk of Alpine breeds fed diets supplemented with rumen-protected conjugated fatty acid.

    Science.gov (United States)

    Bittante, G; Pellattiero, E; Malchiodi, F; Cipolat-Gotet, C; Pazzola, M; Vacca, G M; Schiavon, S; Cecchinato, A

    2014-07-01

    The aim of this study was to test the modeling of curd-firming (CF) measures and to compare the sheep milk of 3 Alpine breeds supplemented with or without rumen-protected conjugated linoleic acid (rpCLA). Twenty-four ewes of the Brogna, Foza, and Lamon breeds were allotted to 6 pens (2 pens/breed) and fed a diet composed of corn grain, corn silage, dried sugar beet pulp, soybean meal, wheat bran, wheat straw, and a vitamin-mineral mixture. The rpCLA supplement (12 g/d per ewe plus 4 g/d for each lamb older than 30 d) was mixed into the diet of 1 pen per sheep breed (3 pens/treatment) to provide an average of 0.945 and 0.915 g/d per ewe of the cis-9,trans-11 C18:2 and trans-10,cis-12 C18:2 conjugated linoleic acid isomers, respectively. The trial started at 38 ± 23 d after parturition, and individual morning milk samples were collected on d 16, 23, 37, 44, and 59 of the trial. Milk samples were analyzed for composition, and duplicate samples were assessed for milk coagulation properties (MCP). A total of 180 CF measures for each sample (1 every 15s) were recorded. Model parameters were the rennet coagulation time, the asymptotic potential CF, the CF instant rate constant, the syneresis instant rate constant, the maximum CF achieved within 45 min (CFmax), and the time at achievement of CFmax. The data were analyzed using a hierarchical model that considered the fixed effects of breed, diet, lamb birth, and initial days in milk, which were tested on individual ewe (random) variance; the fixed effect of sampling day, which was tested on the within-ewe sample (random) variance; and the fixed effect of instrument or cuvette position (only for MCP), which was tested on the residual (replicates within samples) variance. The local Alpine sheep breeds displayed similar milk compositions, traditional MCP, and CF modeling parameters. Supplementation with rpCLA triggered changes in milk composition and worsened MCP (e.g., delayed rennet coagulation time, slower CF instant rate

  4. Short communication: Variation in the composition and properties of Swedish raw milk for ultra-high temperature processing.

    Science.gov (United States)

    Karlsson, Maria A; Langton, Maud; Innings, Fredrik; Wikström, Malin; Lundh, Åse Sternesjö

    2017-02-08

    The composition and properties of raw milk are of great importance for the quality and shelf life of the final dairy product, especially in products with a long shelf life [e.g., ultra-high temperature (UHT)-treated milk]. The objective of this study was to investigate the compositional variation in raw milk samples before processing at the dairy plant. Moreover, we wanted to investigate the effect of the UHT process on this variation (i.e., if the same variation could be observed in the corresponding UHT milk). The quality traits analyzed included detailed milk composition, counts of total and psychrotrophic bacteria, proteolytic activity, and color, as well as predictive measures of stability (i.e., ethanol stability and heat coagulating time). Samples of raw milk and the corresponding produced UHT milk were collected and analyzed on a monthly basis during 1 yr. Principal component analysis was used to identify months showing similarities and differences with respect to total variation. In contrast to previous studies, we observed only small variations between months and no clear effect of season for the raw milk. For the UHT milk, July and the winter months (December, January, and February) tended to separate from the other months. Quality traits showing significant variation were only to some extent identical in raw milk and UHT-processed milk. A better understanding of the natural variation in raw milk quality will provide opportunities to improve the shelf life of UHT-treated milk products.

  5. Processing effects on physicochemical properties of creams formulated with modified milk fat.

    Science.gov (United States)

    Bolling, J C; Duncan, S E; Eigel, W N; Waterman, K M

    2005-04-01

    Type of thermal process [high temperature, short time pasteurization (HTST) or ultra-high temperature pasteurization (UHT)] and homogenization sequence (before or after pasteurization) were examined for influence on the physicochemical properties of natural cream (20% milk fat) and creams formulated with 20% low-melt, fractionated butteroil emulsified with skim milk, or buttermilk and butter-derived aqueous phase. Homogenization sequence influenced physicochemical makeup of the creams. Creams homogenized before pasteurization contained more milk fat surface material, higher phospholipid levels, and less protein at the milk fat interface than creams homogenized after pasteurization. Phosphodiesterase I activity was higher (relative to protein on lipid globule surface) when cream was homogenized before pasteurization. Creams formulated with skim milk and modified milk fat had relatively more phospholipid adsorbed at the milk fat interface. Ultra-high-temperature-pasteurized natural and reformulated creams were higher in viscosity at all shear rates investigated compared with HTST-pasteurized creams. High-temperature, short time-pasteurized natural cream was more viscous than HTST-pasteurized reformulated creams at most shear rates investigated. High-temperature, short time-pasteurized creams had better emulsion stability than UHT-pasteurized creams. Cream formulated with buttermilk had creaming stability most comparable to natural cream, and cream formulated with skim milk and modified butteroil was least stable to creaming. Most creams feathered in a pH range of 5.00 to 5.20, indicating that they were moderately stable to slightly unstable emulsions. All processing sequences yielded creams within sensory specifications with the exception of treatments homogenized before UHT pasteurization and skim milk formulations homogenized after UHT pasteurization.

  6. THE IMPORTANCE OF MONITORING CHANGES IN MILK FAT TO MILK PROTEIN RATIO IN HOLSTEIN COWS DURING LACTATION

    Directory of Open Access Journals (Sweden)

    Vladimír ČEJNA

    2006-07-01

    Full Text Available Milk samples of 24 pure-bred Holstein cows were taken during lactation and changes in milk fat to milk protein ratio and quality of rennet gel were evaluated. The cows were either fi rst (n=12 or second (n=12 calvers, in the same phase of lactation. The individual milk samples were taken on average on the day 25, 45, 73, 101, 133, 166, 199, 224, 253 and 280 of lactation and the following mean values of the F/P ratio were found: 1.91; 1.45; 1.38; 1.28; 1.22; 1.14; 1.26; 1.21; 1.09; 1.18. High values in the fi rst phase suggest a great energy defi ciency. The quality of rennet gel was also worst in the fi rst phase of lactation.

  7. Qualitative Study of Functional Groups and Antioxidant Properties of Soy-Based Beverages Compared to Cow Milk

    OpenAIRE

    Alessandra Durazzo; Paolo Gabrielli; Pamela Manzi

    2015-01-01

    Soy-based beverages are a source of high quality proteins and balanced nutrients; they thus represent an alternative to milk in case of allergy to cow milk proteins or intolerance to lactose. In this research, antioxidant properties of soy-based beverages and UHT cow milk were studied. In addition, color parameters, by a quick and non-destructive methodology, were studied in order to verify a possible correlation with antioxidant properties and a qualitative analysis of the major functional ...

  8. Transcobalamin from cow milk: isolation and physico-chemical properties

    DEFF Research Database (Denmark)

    Fedosov, Sergey; Petersen, Torben Ellebæk; Nexø, Ebba

    1996-01-01

    The concentration of endogenous cobalamin (Cbl) in cow milk was 3.3 nM while the Cbl-binding capacity was 0.05 nM. Both endogenous and newly added Cbl showed similar quantitative distribution between a 280 kDa protein complex (45%) and a 43 kDa Cbl-binder (55%). Long time incubation, as well as u...

  9. Chemical Composition and Rheological Properties of Set Yoghurt Prepared from Skimmed Milk Treated with Horseradish Peroxidase

    Directory of Open Access Journals (Sweden)

    Yan Wen

    2012-01-01

    Full Text Available The aim of this work is to determine the impact of an enzymatic treatment on the fermentation and rheological properties of set yoghurt prepared from skimmed milk. Skimmed bovine milk was treated with horseradish peroxidase added at the level of 645 U per g of proteins in the presence (addition level of 7.8 mmol per L of milk or absence of ferulic acid as a cross-linking agent, and used to prepare set yoghurt with commercial direct vat set starter culture. The evaluation showed that the treatment of skimmed milk with horseradish peroxidase enhanced its apparent viscosity, and storage and loss moduli. The prepared yoghurt contained protein, fat and total solids at 3.49–3.59, 0.46–0.52 and 15.23–15.43 %, respectively, had titratable acidity of 0.83–0.88 %, and no significant difference in the composition was found among the yoghurt samples (p>0.05. Compared to the control yoghurt, the yoghurt prepared from the milk treated with horseradish peroxidase had a higher apparent viscosity, storage and loss moduli and flow behavior indices, especially when ferulic acid was added. Yoghurt samples from the skimmed milk treated either with horseradish peroxidase only or with the additional ferulic acid treatment had better structural reversibility, because their hysteresis loop area during rheological analysis was larger (p<0.05.

  10. Effect of pH and ionic strength on the physicochemical properties of coconut milk emulsions.

    Science.gov (United States)

    Tangsuphoom, N; Coupland, J N

    2008-08-01

    Coconut milk (16% to 17% fat, 1.8% to 2% protein) was extracted from coconut (Cocos nucifera L.) endosperm and diluted in buffer to produce natural oil-in-water emulsions (10 wt% oil). The effect of pH (3 to 7) and NaCl (0 to 200 mM) on the properties and stability, namely, mean particle size, zeta-potential, viscosity, microstructure, and creaming stability, of the natural coconut milk emulsions was investigated. At pH values close to the isoelectric point (IEP) of the coconut proteins (pH 3.5 to 4) and in the absence of NaCl, coconut milk flocculated, but did not coalesce. Flocculation corresponded to low surface charges and was accompanied by an increase in emulsion viscosity. Adding up to 200 mM NaCl to those flocculated emulsions did not change the apparent degree of flocculation. Coconut milk emulsion at pH 6 was negatively charged and not flocculated. Upon addition of salt, the zeta-potential decreased from -16 to -6 mV (at 200 mM NaCl) but this was not sufficient to induce flocculation in coconut milk emulsions. At low pH (coconut milk emulsions only flocculated when the NaCI concentration exceeded 50 mM, as the zeta-potential approached zero.

  11. Shreddability of pizza Mozzarella cheese predicted using physicochemical properties.

    Science.gov (United States)

    Banville, V; Morin, P; Pouliot, Y; Britten, M

    2014-07-01

    This study used rheological techniques such as uniaxial compression, wire cutting, and dynamic oscillatory shear to probe the physical properties of pizza Mozzarella cheeses. Predictive models were built using compositional and textural descriptors to predict cheese shreddability. Experimental cheeses were made using milk with (0.25% wt/wt) or without denatured whey protein and renneted at pH 6.5 or 6.4. The cheeses were aged for 8, 22, or 36 d and then tested at 4, 13, or 22°C for textural attributes using 11 descriptors. Adding denatured whey protein and reducing the milk renneting pH strongly affected cheese mechanical properties, but these effects were usually dependent on testing temperature. Cheeses were generally weaker as they aged. None of the compositional or rheological descriptors taken alone could predict the shredding behavior of the cheeses. Using the stepwise method, an objective selection of a few (<4) relevant descriptors made it possible to predict the production of fines (R(2)=0.82), the percentage of long shreds (R(2)=0.67), and to a lesser degree, the adhesion of cheese to the shredding blade (R(2)=0.45). The principal component analysis markedly contrasted the adhesion of cheese to the shredding blade with other shredding properties such as the production of fines or long shreds. The predictive models and principal component analysis can help manufacturers select relevant descriptors for the development of cheese with optimal mechanical behavior under shredding conditions.

  12. Effect of fat content and homogenization under conventional or ultra-high-pressure conditions on interactions between proteins in rennet curds.

    Science.gov (United States)

    Zamora, A; Trujillo, A J; Armaforte, E; Waldron, D S; Kelly, A L

    2012-09-01

    The objective of this study was to investigate the influence of conventional and ultra-high-pressure homogenization on interactions between proteins within drained rennet curds. The effect of fat content of milk (0.0, 1.8, or 3.6%) and homogenization treatment on dissociation of proteins by different chemical agents was thus studied. Increasing the fat content of raw milk increased levels of unbound whey proteins and calcium-bonded caseins in curds; in contrast, hydrophobic interactions and hydrogen bonds were inhibited. Both homogenization treatments triggered the incorporation of unbound whey proteins in the curd, and of caseins through ionic bonds involving calcium salts. Conventional homogenization-pasteurization enhanced interactions between caseins through hydrogen bonds and hydrophobic interactions. In contrast, ultra-high-pressure homogenization impaired hydrogen bonding, led to the incorporation of both whey proteins and caseins through hydrophobic interactions and increased the amount of unbound caseins. Thus, both homogenization treatments provoked changes in the protein interactions within rennet curds; however, the nature of the changes depended on the homogenization conditions.

  13. Associations between pathogen-specific cases of subclinical mastitis and milk yield, quality, protein composition, and cheese-making traits in dairy cows.

    Science.gov (United States)

    Bobbo, T; Ruegg, P L; Stocco, G; Fiore, E; Gianesella, M; Morgante, M; Pasotto, D; Bittante, G; Cecchinato, A

    2017-03-29

    The aim of this study was to investigate associations between pathogen-specific cases of subclinical mastitis and milk yield, quality, protein composition, and cheese-making traits. Forty-one multibreed herds were selected for the study, and composite milk samples were collected from 1,508 cows belonging to 3 specialized dairy breeds (Holstein Friesian, Brown Swiss, and Jersey) and 3 dual-purpose breeds of Alpine origin (Simmental, Rendena, and Grey Alpine). Milk composition [i.e., fat, protein, casein, lactose, pH, urea, and somatic cell count (SCC)] was analyzed, and separation of protein fractions was performed by reversed-phase high performance liquid chromatography. Eleven coagulation traits were measured: 5 traditional milk coagulation properties [time from rennet addition to milk gelation (RCT, min), curd-firming rate as the time to a curd firmness (CF) of 20 mm (k20, min), and CF at 30, 45, and 60 min from rennet addition (a30, a45, and a60, mm)], and 6 new curd firming and syneresis traits [potential asymptotical CF at an infinite time (CFP, mm), curd-firming instant rate constant (kCF, % × min(-1)), curd syneresis instant rate constant (kSR, % × min(-1)), modeled RCT (RCTeq, min), maximum CF value (CFmax, mm), and time at CFmax (tmax, min)]. We also measured 3 cheese yield traits, expressing the weights of total fresh curd (%CYCURD), dry matter (%CYSOLIDS), and water (%CYWATER) in the curd as percentages of the weight of the processed milk, and 4 nutrient recovery traits (RECPROTEIN, RECFAT, RECSOLIDS, and RECENERGY), representing the percentage ratio between each nutrient in the curd and milk. Milk samples with SCC > 100,000 cells/mL were subjected to bacteriological examination. All samples were divided into 7 clusters of udder health (UH) status: healthy (cows with milk SCC cheese production was observed in the 2 UH status groups with the highest milk SCC (i.e., contagious IMI and culture-negative samples with high SCC), revealing a discrepancy

  14. Effect of Disaccharides on Ion Properties in Milk-Based Systems

    NARCIS (Netherlands)

    Gao, R.; Leeuwen, van H.P.; Temminghoff, E.J.M.; Valenberg, van H.J.F.; Eisner, M.D.; Boekel, van M.A.J.S.

    2010-01-01

    The mean spherical approximation (MSA) theory is used to explain the impact of sugars on ion properties in milk-based systems by taking into account electrostatic interactions and volume exclusion effects. This study first focuses on the changes in Ca2+ activity and pH in a solution consisting of Ca

  15. Rheological properties of concentrated skim milk: importance of soluble minerals in the changes in viscosity during storage.

    Science.gov (United States)

    Bienvenue, A; Jiménez-Flores, R; Singh, H

    2003-12-01

    Properties of condensed milks prior to spray drying dictate to a large extent the functionality of the resulting milk powder. Rheological properties of concentrated skim milk, with total solids content of 45% but different mineral content, were studied as a function of shear rate and storage time at 50 degrees C. These milks are proposed as a model to study the effects of minerals on rheology and age gellation of condensed milk prior to drying. During storage of the concentrated milk, the apparent viscosity, particularly after 4 h, increased markedly at all shear rates studied. The yield stress also increased steeply after 4 h of storage at 50 degrees C. The changes in apparent viscosity of concentrated milk stored for up to 4 h were largely reversible under high shear, but irreversible in samples stored for longer time. The appearance of yield stress suggested the presence of reversible flocculation arising from weak attraction between casein micelles, with a transition from reversible to irreversible aggregation during storage. Particle size analysis confirmed irreversible aggregation and fusion of casein micelles during storage. Gradual reduction of mineral content of concentrated milks resulted in a marked decrease in the apparent viscosity and casein micelle aggregation during storage, while addition of minerals to milk had the opposite effect. The results demonstrated that the soluble mineral content is very important in controlling the storage-induced changes in the rheology of concentrated milks.

  16. Effect of homogenization of cream on composition, yield, and functionality of Cheddar cheese made from milk supplemented with ultrafiltered milk

    OpenAIRE

    Oommen, Bonney; Mistry, Vikram; Nair, Manoj

    2000-01-01

    International audience; Cheddar cheeses were made from milks supplemented with ultrafiltered skim milk to 4.57 and 5.93% protein and from milks without supplementation to serve as controls (3.18% protein). Milks were standardized (casein-to-fat ratio of 0.7) with unhomogenized cream or homogenized (6.9/3.45 MPa) cream. The six treatments were replicated five times. Rennet clotting time decreased with protein concentration and homogenization of cream increased it. $\\rm k_{20}$, the time to rea...

  17. Cell Surface Properties of Lactococcus lactis Reveal Milk Protein Binding Specifically Evolved in Dairy Isolates

    Directory of Open Access Journals (Sweden)

    Mariya Tarazanova

    2017-09-01

    Full Text Available Surface properties of bacteria are determined by the molecular composition of the cell wall and they are important for interactions of cells with their environment. Well-known examples of bacterial interactions with surfaces are biofilm formation and the fermentation of solid materials like food and feed. Lactococcus lactis is broadly used for the fermentation of cheese and buttermilk and it is primarily isolated from either plant material or the dairy environment. In this study, we characterized surface hydrophobicity, charge, emulsification properties, and the attachment to milk proteins of 55 L. lactis strains in stationary and exponential growth phases. The attachment to milk protein was assessed through a newly developed flow cytometry-based protocol. Besides finding a high degree of biodiversity, phenotype-genotype matching allowed the identification of candidate genes involved in the modification of the cell surface. Overexpression and gene deletion analysis allowed to verify the predictions for three identified proteins that altered surface hydrophobicity and attachment of milk proteins. The data also showed that lactococci isolated from a dairy environment bind higher amounts of milk proteins when compared to plant isolates. It remains to be determined whether the alteration of surface properties also has potential to alter starter culture functionalities.

  18. Cell Surface Properties of Lactococcus lactis Reveal Milk Protein Binding Specifically Evolved in Dairy Isolates.

    Science.gov (United States)

    Tarazanova, Mariya; Huppertz, Thom; Beerthuyzen, Marke; van Schalkwijk, Saskia; Janssen, Patrick; Wels, Michiel; Kok, Jan; Bachmann, Herwig

    2017-01-01

    Surface properties of bacteria are determined by the molecular composition of the cell wall and they are important for interactions of cells with their environment. Well-known examples of bacterial interactions with surfaces are biofilm formation and the fermentation of solid materials like food and feed. Lactococcus lactis is broadly used for the fermentation of cheese and buttermilk and it is primarily isolated from either plant material or the dairy environment. In this study, we characterized surface hydrophobicity, charge, emulsification properties, and the attachment to milk proteins of 55 L. lactis strains in stationary and exponential growth phases. The attachment to milk protein was assessed through a newly developed flow cytometry-based protocol. Besides finding a high degree of biodiversity, phenotype-genotype matching allowed the identification of candidate genes involved in the modification of the cell surface. Overexpression and gene deletion analysis allowed to verify the predictions for three identified proteins that altered surface hydrophobicity and attachment of milk proteins. The data also showed that lactococci isolated from a dairy environment bind higher amounts of milk proteins when compared to plant isolates. It remains to be determined whether the alteration of surface properties also has potential to alter starter culture functionalities.

  19. Predictive ability of mid-infrared spectroscopy for major mineral composition and coagulation traits of bovine milk by using the uninformative variable selection algorithm.

    Science.gov (United States)

    Visentin, G; Penasa, M; Gottardo, P; Cassandro, M; De Marchi, M

    2016-10-01

    Milk minerals and coagulation properties are important for both consumers and processors, and they can aid in increasing milk added value. However, large-scale monitoring of these traits is hampered by expensive and time-consuming reference analyses. The objective of the present study was to develop prediction models for major mineral contents (Ca, K, Mg, Na, and P) and milk coagulation properties (MCP: rennet coagulation time, curd-firming time, and curd firmness) using mid-infrared spectroscopy. Individual milk samples (n=923) of Holstein-Friesian, Brown Swiss, Alpine Grey, and Simmental cows were collected from single-breed herds between January and December 2014. Reference analysis for the determination of both mineral contents and MCP was undertaken with standardized methods. For each milk sample, the mid-infrared spectrum in the range from 900 to 5,000cm(-1) was stored. Prediction models were calibrated using partial least squares regression coupled with a wavenumber selection technique called uninformative variable elimination, to improve model accuracy, and validated both internally and externally. The average reduction of wavenumbers used in partial least squares regression was 80%, which was accompanied by an average increment of 20% of the explained variance in external validation. The proportion of explained variance in external validation was about 70% for P, K, Ca, and Mg, and it was lower (40%) for Na. Milk coagulation properties prediction models explained between 54% (rennet coagulation time) and 56% (curd-firming time) of the total variance in external validation. The ratio of standard deviation of each trait to the respective root mean square error of prediction, which is an indicator of the predictive ability of an equation, suggested that the developed models might be effective for screening and collection of milk minerals and coagulation properties at the population level. Although prediction equations were not accurate enough to be proposed

  20. Thermal properties of milk fat, xanthine oxidase, caseins and whey proteins in pulsed electric field-treated bovine whole milk.

    Science.gov (United States)

    Sharma, Pankaj; Oey, Indrawati; Everett, David W

    2016-09-15

    Thermodynamics of milk components (milk fat, xanthine oxidase, caseins and whey proteins) in pulsed electric field (PEF)-treated milk were compared with thermally treated milk (63 °C for 30 min and 73 °C for 15s). PEF treatments were applied at 20 or 26 kV cm(-1) for 34 μs with or without pre-heating of milk (55 °C for 24s), using bipolar square wave pulses in a continuous mode of operation. PEF treatments did not affect the final temperatures of fat melting (Tmelting) or xanthine oxidase denaturation (Tdenaturation), whereas thermal treatments increased both the Tmelting of milk fat and the Tdenaturation for xanthine oxidase by 2-3 °C. Xanthine oxidase denaturation was ∼13% less after PEF treatments compared with the thermal treatments. The enthalpy change (ΔH of denaturation) of whey proteins decreased in the treated-milk, and denaturation increased with the treatment intensity. New endothermic peaks in the calorimetric thermograms of treated milk revealed the formation of complexes due to interactions between MFGM (milk fat globule membrane) proteins and skim milk proteins. Evidence for the adsorption of complexes onto the MFGM surface was obtained from the increase in surface hydrophobicity of proteins, revealing the presence of unfolded hydrophobic regions.

  1. Effect of organic farming on selected raw cow milk components and properties

    Directory of Open Access Journals (Sweden)

    Ivana Cermanová

    2011-01-01

    Full Text Available Organic dairying is an alternative for friendly exploitation of environment. This paper was focused on impacts of organic dairying on milk composition and properties. The conventional (C cow milk was compared to organic (O milk. Holstein bulk milk samples (BMSs from winter and summer season in 4 C and 4 O (n = 32 and 32 BMSs; 2 years herds were investigated. 6 herds were grazed and 2 C herds were not grazed. Mean O cow milk yield (MY, 305 lactation days was 7037.3 ± 421.5 and C MY 7015.8 ± 1068.1 kg. Higher values (P < 0.05 in O milk had: log acetone (0.7321 > 0.6048; titration acidity (8.34 > 7.82 ml 0.25 mol.l−1 NaOH; alcohol stability (0.6 > 0.44 ml; time for enzymatic coagulation (150.75 > 115.03 second; whey protein (0.54 > 0.49%; fat/crude protein (1.2 > 1.15; milk fermentation ability (FAM by titration (31.45 > 22.18 ml 0.25 mol.l−1 NaOH. Lower values (P < 0.05 in O milk had: solids–not–fat (8.64 < 8.73%; urea content (19.91 < 29.03 mg.100ml−1; electrical conductivity (3.66 < 4.08 mS.cm−1; whey volume (32.03 < 34.53 ml; crude protein (3.16 < 3.25%; casein (2.47 < 2.58%; non–protein nitrogen compounds (0.15 < 0.18%; urea nitrogen in non-protein nitrogen ratio (40.81 < 49.0%; casein numbers for crude protein and true protein (78.12 < 79.58 and 81.99 < 84.11%; coli bacteria count in normal and logarithm form (330.56 < 1502.92 CFU.ml−1 and 1.484 < 2.5823; actual yoghurt acidity (4.71 < 4.8. O cows suffered probably from lower energy and nitrogen compounds intake due to feeding under mentioned conditions. O milk could be a little better environment for yoghurt cultivation.

  2. [Odd- and branched-chain fatty acids in milk fat--characteristic and health properties].

    Science.gov (United States)

    Adamska, Agata; Rutkowska, Jarosława

    2014-08-22

    This review analyzes the current state of knowledge on odd- and branched-chain fatty acids present in milk fat. Special attention is devoted to the characteristic, synthesis in ruminants, factors affecting their content in milk fat and pro-health properties of these compounds. The group of odd- and branched-chain fatty acids includes mainly saturated fatty acids with one or more methyl branches in the iso or anteiso position. These fatty acids are largely derived from ruminal bacteria and they have been transferred to ruminant tissue (milk and meat). For that reason they have been used as biomarkers of rumen fermentation. Odd- and branched-chain fatty acids are exogenous products for humans, and therefore have specific properties. The results of research from recent decades show that odd- and branched-chain fatty acids have anti-cancer activity. Branched-chain fatty acids may reduce the incidence of necrotizing enterocolitis. Additionally, these compounds have a beneficial effect on proper tissue function and on functioning and development of the infant gut, whereas odd-chain fatty acids are considered as biomarkers of milk fat intake by humans. So far, not all the mechanisms of activity of these compounds are known thoroughly. They should be more carefully studied for application of their biological effects in prevention and treatment.

  3. 山羊乳农家干酪加工中凝乳酶的筛选研究%The Screening Study of Rennet in Goat Cottage Cheese Processing

    Institute of Scientific and Technical Information of China (English)

    马兆瑞; 祝战斌; 姚瑞祺; 张鹏; 王智民

    2012-01-01

    选取5种凝乳酶应用于山羊乳农家千酪加工,通过不同凝乳酶在山羊乳农家干酪生产中的凝乳特性、干酪出品率及对干酪品质影响三方面试验研究,结果表明:液态小牛皱胃酶是山羊乳农家干酪加工的最佳凝乳酶,微生物凝乳酶次之,番木瓜蛋白酶不适合使用。%5 kinds of rennet used in goat cottage cheese processing were selected, coagulation properties of cheese, yield rate and quality of cheese were analyzed. The results show the liquid calf rennet is the best rennet for goat cottage cheese processing, microbial rennet the second, papaya protease is not suitable for using.

  4. Effect of dairy farming system, herd, season, parity, and days in milk on modeling of the coagulation, curd firming, and syneresis of bovine milk.

    Science.gov (United States)

    Bittante, G; Cipolat-Gotet, C; Malchiodi, F; Sturaro, E; Tagliapietra, F; Schiavon, S; Cecchinato, A

    2015-04-01

    The objectives of this study were to characterize the variation in curd firmness model parameters obtained from coagulating bovine milk samples, and to investigate the effects of the dairy system, season, individual farm, and factors related to individual cows (days in milk and parity). Individual milk samples (n = 1,264) were collected during the evening milking of 85 farms representing different environments and farming systems in the northeastern Italian Alps. The dairy herds were classified into 4 farming system categories: traditional system with tied animals (29 herds), modern dairy systems with traditional feeding based on hay and compound feed (30 herds), modern dairy system with total mixed ration (TMR) that included silage as a large proportion of the diet (9 herds), and modern dairy system with silage-free TMR (17 herds). Milk samples were analyzed for milk composition and coagulation properties, and parameters were modeled using curd firmness measures (CFt) collected every 15 s from a lacto-dynamographic analysis of 90 min. When compared with traditional milk coagulation properties (MCP), the curd firming measures showed greater variability and yielded a more accurate description of the milk coagulation process: the model converged for 93.1% of the milk samples, allowing estimation of 4 CFt parameters and 2 derived traits [maximum CF (CF(max)) and time from rennet addition to CF(max) (t(max))] for each sample. The milk samples whose CFt equations did not converge showed longer rennet coagulation times obtained from the model (RCT(eq)) and higher somatic cell score, and came from less-productive cows. Among the sources of variation tested for the CFt parameters, dairy herd system yielded the greatest differences for the contrast between the traditional farm and the 3 modern farms, with the latter showing earlier coagulation and greater instant syneresis rate constant (k(SR)). The use of TMR yielded a greater tmax because of a higher instant curd

  5. The impact of the manufacturing process on the hardness and sensory properties of milk chocolate

    Directory of Open Access Journals (Sweden)

    Zarić Danica B.

    2012-01-01

    Full Text Available The aim of this paper was to examine the impact of the manufacturing process on the textural characteristics and sensory properties of milk chocolate. The research was conducted on the samples of chocolate produced in a ball mill during 30, 60 and 90 minutes of refining, each of them being pre-crystallized at 26, 28 and 30°C. A chocolate mass of identical ingredient composition was also produced using a standard manufacturing process at the same pre-crystallization temperatures. Chocolate hardness was examined using a piece of equipment called Texture Analyser, measuring the stress intensity which leads to chocolate crushing. Sensory analysis was performed using the point scoring method. The new manufacturing process, i.e. the manufacturing of chocolate in a ball mill improves sensory properties and hardness of milk chocolate. [Projekat Ministarstva nauke Republike Srbije, br. TR 31014

  6. Rheological and physical properties of camel and cow milk gels enriched with phosphate and calcium during acid-induced gelation

    National Research Council Canada - National Science Library

    Kamal, Mohammad; Foukani, Mohammed; Karoui, Romdhane

    2017-01-01

    .... The increase of the added CaCl2 levels improved significantly the gelation properties of camel and cow milk gels, since a reduction in the gelation time and an increase in the gel firmness were observed...

  7. Heat stability and acid gelation properties of calcium-enriched reconstituted skim milk affected by ultrasonication.

    Science.gov (United States)

    Chandrapala, Jayani; Bui, Don; Kentish, Sandra; Ashokkumar, Muthupandian

    2014-05-01

    The aggregation of proteins after heating of calcium-fortified milks has been an ongoing problem in the dairy industry. This undesirable effect restricts the manufacture of calcium rich dairy products. To overcome this problem, a completely new approach in controlling the heat stability of dairy protein solutions, developed in our lab, has been employed. In this approach, high intensity, low frequency ultrasound is applied for a very short duration after a pre-heating step at ⩾70 °C. The ultrasound breaks apart whey/whey and whey/casein aggregates through the process of acoustic cavitation. Protein aggregates do not reform on subsequent post-heating, thereby making the systems heat stable. In this paper, the acid gelation properties of ultrasonicated calcium-enriched skim milks have also been investigated. It is shown that ultrasonication alone does not change the gelation properties significantly whereas a sequence of preheating (72 °C/1 min) followed by ultrasonication leads to decreased gelation times, decreased gel syneresis and increased skim milk viscosity in comparison to heating alone. Overall, ultrasonication has the potential to provide calcium-fortified dairy products with increased heat stability. However, enhanced gelation properties can only be achieved when ultrasonication is completed in conjunction with heating.

  8. Gamma irradiation influence on physical properties of milk proteins

    Energy Technology Data Exchange (ETDEWEB)

    Ciesla, K. E-mail: kciesla@orange.ichtj.waw.pl; Salmieri, S.; Lacroix, M.; Le Tien, C

    2004-10-01

    Gamma irradiation was found to be an effective method for the improvement of both barrier and mechanical properties of the edible films and coatings based on calcium and sodium caseinates alone or combined with some globular proteins. Our current studies concern gamma irradiation influence on the physical properties of calcium caseinate-whey protein isolate-glycerol (1:1:1) solutions and gels, used for films preparation. Irradiation of solutions was carried out with Co-60 gamma rays applying 0 and 32 kGy dose. The increase in viscosity of solutions was found after irradiation connected to induced crosslinking. Lower viscosity values were detected, however, after heating of the solutions irradiated with a 32 kGy dose than after heating of the non-irradiated ones regarding differences in the structure of gels and resulting in different temperature-viscosity curves that were recorded for the irradiated and the non-irradiated samples during heating and cooling. Creation of less stiff but better ordered gels after irradiation arises probably from reorganisation of aperiodic helical phase and {beta}-sheets, in particular from increase of {beta}-strands, detected by FTIR. Films obtained from these gels are characterised by improved barrier properties and mechanical resistance and are more rigid than those prepared from the non-irradiated gels. The route of gel creation was investigated for the control and the irradiated samples during heating and the subsequent cooling.

  9. Gamma irradiation influence on physical properties of milk proteins

    Science.gov (United States)

    Cieśla, K.; Salmieri, S.; Lacroix, M.; Tien, C. Le

    2004-09-01

    Gamma irradiation was found to be an effective method for the improvement of both barrier and mechanical properties of the edible films and coatings based on calcium and sodium caseinates alone or combined with some globular proteins. Our current studies concern gamma irradiation influence on the physical properties of calcium caseinate-whey protein isolate-glycerol (1:1:1) solutions and gels, used for films preparation. Irradiation of solutions was carried out with Co-60 gamma rays applying 0 and 32 kGy dose. The increase in viscosity of solutions was found after irradiation connected to induced crosslinking. Lower viscosity values were detected, however, after heating of the solutions irradiated with a 32 kGy dose than after heating of the non-irradiated ones regarding differences in the structure of gels and resulting in different temperature-viscosity curves that were recorded for the irradiated and the non-irradiated samples during heating and cooling. Creation of less stiff but better ordered gels after irradiation arises probably from reorganisation of aperiodic helical phase and β-sheets, in particular from increase of β-strands, detected by FTIR. Films obtained from these gels are characterised by improved barrier properties and mechanical resistance and are more rigid than those prepared from the non-irradiated gels. The route of gel creation was investigated for the control and the irradiated samples during heating and the subsequent cooling.

  10. Genomic Regions Affecting Cheese Making Properties Identified in Danish Holsteins

    DEFF Research Database (Denmark)

    Gregersen, Vivi Raundahl; Bertelsen, Henriette Pasgaard; Poulsen, Nina Aagaard

    The cheese renneting process is affected by a number of factors associated to milk composition and a number of Danish Holsteins has previously been identified to have poor milk coagulation ability. Therefore, the aim of this study was to identify genomic regions affecting the technological...

  11. Genomic Regions Affecting Cheese Making Properties Identified in Danish Holsteins

    DEFF Research Database (Denmark)

    Gregersen, Vivi Raundahl; Bertelsen, Henriette Pasgaard; Poulsen, Nina Aagaard

    The cheese renneting process is affected by a number of factors associated to milk composition and a number of Danish Holsteins has previously been identified to have poor milk coagulation ability. Therefore, the aim of this study was to identify genomic regions affecting the technological...

  12. Functional properties and applications of edible films made of milk proteins.

    Science.gov (United States)

    Chen, H

    1995-11-01

    Edible films and coatings based on milk proteins have been developed to be used as a protective layer on foods or between food components. The most important functionalities of an edible film or coating include control of mass transfers, mechanical protection, and sensory appeal. Control of mass transfers involves preventing foods from desiccation, regulating microenvironments of gases around foods, and controlling migration of ingredients and additives in the food systems. Adequate mechanical strength of an edible film is necessary to protect the integrity of packaging throughout distribution. The sensory properties of an edible coating or film are a key factor for acceptance of final products. Simple milk protein films are good barriers to gas transfers because of their complex intermolecular bindings. Lipid is frequently incorporated into protein films to improve their properties as barriers to moisture vapor. Protein films are distinctly different in mechanical profiles from those films made of other materials. Approaches traditionally used in material sciences have been adapted and modified for studying the functionality of edible films. Potential uses of innovative processing technologies in film making to alter the film functionality are briefly discussed. A survey of potential applications of edible film based on milk protein is presented.

  13. Optimization of the Formulation of Prebiotic Milk Chocolate Based on Rheological Properties

    Directory of Open Access Journals (Sweden)

    Hannaneh Farzanmehr

    2009-01-01

    Full Text Available Rheological properties are very important parameters in the production of products with high-quality and desirable texture. So far, many attempts to produce low-calorie milk chocolate have not succeeded. Therefore, the present study aims to evaluate the effects of sugar substitutes on rheological characteristics of prebiotic milk chocolate using Simplex-lattice mixture design. For doing this, a prebiotic compound (inulin with two bulking agents (polydextrose and maltodextrin at different levels (0–100 % along with sucralose were used. Fifteen formulations covering the entire range of a triangular simplex were examined in order to find the optimum levels. All chocolates showed thixotropic and shear thinning behaviour and among the evaluated mathematical models, Casson model showed the best fitting for predicting rheological properties. According to our findings, chocolate formulations containing high levels of sugar substitutes (where a single component predominated had higher moisture content, Casson viscosity and yield stress than others, including the control. In contrast, the lowest moisture content, Casson viscosity and yield stress were observed at medium levels. Therefore, the optimum values for substitution of sucrose and production of a low-calorie prebiotic milk chocolate are 8–28 % and 67–86 % for inulin, 0–19 % and 31–69 % for polydextrose and 0–47 % for maltodextrin, respectively.

  14. Distinct composition of bovine milk from Jersey and Holstein-Friesian cows with good, poor or non-coagulation properties as reflected in protein genetic variants and isoforms

    DEFF Research Database (Denmark)

    Jensen, Hanne Bak; Poulsen, Nina Aagaard; Andersen, Kell Kleiner

    2012-01-01

    of minerals (Ca, P, Mg) were identified in poorly coagulating and noncoagulating milk in comparison with milk with good coagulation properties. Liquid chromatography/electrospray ionization-mass spectrometry revealed the presence of a great variety of genetic variants of the major milk proteins, namely, αS1...

  15. Effect of gel firmness at cutting time, pH, and temperature on rennet coagulation and syneresis: an in situ 1H NMR relaxation study.

    Science.gov (United States)

    Hansen, Christian Lyndgaard; Rinnan, Asmund; Engelsen, Søren Balling; Janhøj, Thomas; Micklander, Elisabeth; Andersen, Ulf; van den Berg, Frans

    2010-01-13

    The objective of this study was to monitor rennet-induced milk gel formation and mechanically induced gel syneresis in situ by low-field NMR. pH, temperature, and gel firmness at cutting time were varied in a factorial design. The new curve-fitting method Doubleslicing revealed that during coagulation two proton populations with distinct transverse relaxation times (T2,1=181, T2,2=465 ms) were present in fractions (f1=98.9%, f2=1.1%). Mechanical cutting of the gel in the NMR tube induced macrosyneresis, which led to the appearance of an additional proton population (T2,3=1500-2200 ms) identified as whey. On the basis of NMR quantification of whey water the syneresis rate was calculated and found to be significantly dependent on pH and temperature.

  16. Mechanical and permeability properties of milk protein films

    Directory of Open Access Journals (Sweden)

    Marília I.S. Folegatti

    1998-01-01

    Full Text Available Edible films present a potential alternative for replacing plastic films used for packaging in food industry. One of the major advantages is the environmental appeal of this technology, which produces no packaging waste. Some films made with other edible materials have found commercial applications, and many more are being developed using a myriad of food based components. This paper focuses on some important characteristics of films produced with sodium and calcium caseinates. The effects of caseinate type and concentration, plasticizer concentration and pH were studied. Major parameters investigated were solubility, tensile properties, water vapour and oxygen permeabilities. Caseinate films showed high solubility at pH range 6.0-8.0 and complete insolubility at pH 3.0 and 4.0. Calcium caseinate films had a higher tensile strength and a lower % elongation at break than sodium caseinate films. There was not significant difference in water vapour and oxygen permeabilities between sodium and calcium caseinate films.Filmes comestíveis representam uma alternativa potencial para a substituição de filmes plásticos .empregados em embalagem de alimentos. Uma de suas maiores vantagens relaciona-se com o problema de poluição ambiental por não gerar material residual. Filmes elaborados com outros materiais comestíveis não protéicos têm encontrado aplicação comercial e muitos outros ainda estão sendo pesquisados, usando uma grande variedade de componentes alimentares. Este trabalho estuda algumas características importantes dos filmes produzidos com caseinatos de sódio e de cálcio. Os efeitos do tipo e concentração de caseinato, concentração de plastificante e do pH são investigados. Os parâmetros pesquisados foram a solubilidade, propriedades de tração e permeabilidade a vapor de água e oxigênio. Filmes de caseinato apresentaram alta solubilidade na faixa de pH entre 6.0 e 8.0 e completa insolubilidade em pH 3.0 e 4.0. Maior

  17. Genetic variation and posttranslational modification of bovine κ-casein: effects on caseino-macropeptide release during renneting.

    Science.gov (United States)

    Jensen, Hanne B; Pedersen, Katrine S; Johansen, Lene B; Poulsen, Nina A; Bakman, Mette; Chatterton, Dereck E W; Larsen, Lotte B

    2015-02-01

    Chymosin-induced cleavage of κ-casein (κ-CN) occurs during the first enzymatic phase in milk coagulation during cheese manufacturing, where the hydrophilic C-terminal peptide of κ-CN, named caseino-macropeptide (CMP), is released into the whey. The CMP peptide is known for its rather heterogeneous composition with respect to both genetic variation and multiple posttranslational modifications, including phosphorylation and O-linked glycosylation. An approach of liquid chromatography coupled with mass spectrometry was used to investigate (1) the overall protein profile and (2) the release of various forms of CMP after addition of chymosin to individual cow milk samples from 2 breeds, Danish Jersey (DJ) and Danish Holstein-Friesian (DH). The cows were selected to represent distinct homo- and heterozygous types of the κ-CN genetic variants A, B, and E (i.e., genotypes AA, BB, AB, EE, and AE). Initially, investigation of the protein profile showed milk with κ-CN BB exhibited the highest relative content of κ-CN, whereas AE milk exhibited the lowest, and after 40min of renneting >90% of intact κ-CN was hydrolyzed by chymosin in milk representing all κ-CN genotype. By in-depth analysis of the CMP chromatographic profile, multiple CMP isoforms with 1 to 3 O-linked glycans (1-3 G) and 1 to 3 phosphate groups (1-3 P) were identified, as well as nonmodified CMP isoforms. The number of identified CMP isoforms varied to some extent between breeds (21CMP isoforms identified in DJ, 26CMP isoforms in DH) and between κ-CN genetic variants (CMP variant A being the most heterogeneous compared with CMP B and E), as well as between individual samples within each breed. The predominant forms of glycans attached to CMP were found to be the acidic tetrasaccharide {N-acetyl-neuraminic acid α(2-3)galactose β(1-3)[N-acetyl-neuraminic acid α(2-6)]N-acetyl galactose} or trisaccharides {N-acetyl-neuraminic acid α(2-3)galactose β(1-3)N-acetyl galactose and galactose β(1-3)[N

  18. Effect of ultrasonic homogenization on the Vis/NIR bulk optical properties of milk.

    Science.gov (United States)

    Aernouts, Ben; Van Beers, Robbe; Watté, Rodrigo; Huybrechts, Tjebbe; Jordens, Jeroen; Vermeulen, Daniel; Van Gerven, Tom; Lammertyn, Jeroen; Saeys, Wouter

    2015-02-01

    The size of colloidal particles in food products has a considerable impact on the product's physicochemical, functional and sensory characteristics. Measurement techniques to monitor the size of suspended particles could, therefore, help to further reduce the variability in production processes and promote the development of new food products with improved properties. Visible and near-infrared (Vis/NIR) spectroscopy is already widely used to measure the composition of agricultural and food products. However, this technology can also be consulted to acquire microstructure-related scattering properties of food products. In this study, the effect of the fat globule size on the Vis/NIR bulk scattering properties of milk was investigated. Variability in fat globule size distribution was created using ultrasonic homogenization of raw milk. Reduction of the fat globule size resulted in a higher wavelength-dependency of both the Vis/NIR bulk scattering coefficient and the scattering anisotropy factor. Moreover, the anisotropy factor and the bulk scattering coefficients for wavelengths above 600 nm were reduced and were dominated by Rayleigh scattering. Additionally, the bulk scattering properties could be well (R(2) ≥ 0.990) estimated from measured particle size distributions by consulting an algorithm based on the Mie solution. Future research could aim at the inversion of this model to estimate the particle size distributions from Vis/NIR spectroscopic measurements.

  19. The impact of manufacturing process on the content of hard triglycerides, hardness and thermal properties of milk chocolate

    OpenAIRE

    Šoronja-Simović Dragana M.; Šereš Zita I.; Dokić Ljubica P.; Pajin Biljana S.; Lončarević Ivana S.; Zarić Danica B.

    2012-01-01

    The rheological and physical properties of the chocolate mass depend on the ingredient composition as well as the manufacturing process. For the purpose of this work, a milk chocolate mass of identical composition and raw materials was manufactured by using the two different manufacturing processes: a standard manufacturing process (SM) in five-roller mills including conching, and an unconventional manufacturing process in a ball mill (R1). The quality of both milk chocolate masses was ...

  20. Minimizing photooxidation in pasteurized milk by optimizing light transmission properties of green polyethylene films.

    Science.gov (United States)

    Intawiwat, N; Wold, J P; Skaret, J; Rukke, E O; Pettersen, M K

    2013-01-01

    The effect of different amounts of transmitted green light on photooxidation in pasteurized milk was studied. Five different green films produced with combinations of pigments and additives to minimize exposure to harmful wavelengths with regard to photosensitizers (400-450 and 600-650 nm) were evaluated. In addition, a non-colored transparent film and an orange film were compared with 1 selected green film. Pasteurized milk (3.9% fat) was packed in an air atmosphere and exposed to light for 14, 20, 26, and 32 h at 4 °C under the different films. Samples stored in the dark were control samples. The results showed that the most-effective green film had low overall light transmission, and also almost completely blocked light wavelengths shorter than 450 nm and wavelengths longer than 600 nm, which prevented photooxidation of riboflavin and chlorophyllic compounds. Chlorophyll degradation was highly correlated with sensory properties (coefficient of determination = 0.80-0.94). To preserve milk quality, total blocking of all visible light would be preferable. If total blocking is not feasible, then light transmission for wavelength below 450 nm and above 650 nm should be minimized (e.g., less than 5%). The newly developed green film can be used as a prototype for protection of dairy products to reduce the degradation of photosensitizers. Copyright © 2013 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  1. Effect of Ultrasonic Treatment on the Extracting Activity of Kid Rennet

    Institute of Scientific and Technical Information of China (English)

    ZHANG Fu-xin; LI Lin-qiang

    2005-01-01

    Using 2-3 weeks kid abomasums as materials, the ultrasound intensity, extracting time, NaC1 concentration and pH value in extracting solution and ratio of abomasums to extracting solution were studied by ultrasonic method. The results showed that the main factor affecting kid rennet activity during extraction was ultrasound intensity, and then NaC1concentration, extracting time and ratio of abomasums to extracting solution in order. Kid rennet activity reached peak with ultrasound intensity 30 W cm-2, extraction time 40 min, NaC1 concentration 8%, pH value 3.0, ratio of abomasums to extracting solution 1:15.

  2. Effects of coagulating enzyme types (commercial calf rennet ...

    African Journals Online (AJOL)

    Aysegul

    2013-09-11

    Sep 11, 2013 ... According to the results, the effects of enzyme type on the titratable acidity, dry .... Rennilase (R. miehei); **Different letters in the same column indicate significant differences among the samples ..... buffaloes' milk in Egypt.

  3. Impact of preacidification of milk and fermentation time on the properties of yogurt.

    Science.gov (United States)

    Peng, Y; Horne, D S; Lucey, J A

    2009-07-01

    Casein interactions play an important role in the textural properties of yogurt. The objective of this study was to investigate how the concentration of insoluble calcium phosphate (CCP) that is associated with casein particles and the length of fermentation time influence properties of yogurt gels. A central composite experimental design was used. The initial milk pH was varied by preacidification with glucono-delta-lactone (GDL), and fermentation time (time to reach pH 4.6 from the initial pH) was altered by varying the inoculum level. We hypothesized that by varying the initial milk pH value, the amount of CCP would be modified and that by varying the length of the fermentation time we would influence the rate and extent of solubilization of CCP during any subsequent gelation process. We believe that both of these factors could influence casein interactions and thereby alter gel properties. Milks were preacidified to pH values from 6.55 to 5.65 at 40 degrees C using GDL and equilibrated for 4 h before inoculation. Fermentation time was varied from 250 to 500 min by adding various amounts of culture at 40 degrees C. Gelation properties were monitored using dynamic oscillatory rheology, and microstructure was studied using fluorescence microscopy. Whey separation and permeability were analyzed at pH 4.6. The preacidification pH value significantly affected the solubilization of CCP. Storage modulus values at pH 4.6 were positively influenced by the preacidification pH value and negatively affected by fermentation time. The value for the loss tangent maximum during gelation was positively affected by the preacidification pH value. Fermentation time positively affected whey separation and significantly influenced the rate of CCP dissolution during fermentation, as CCP dissolution was a slow process. Longer fermentation times resulted in greater loss of CCP at the pH of gelation. At the end of fermentation (pH approximately 4.6), virtually all CCP was dissolved

  4. The impact of the manufacturing process on the hardness and sensory properties of milk chocolate

    OpenAIRE

    Zarić Danica B.; Pajin Biljana S.; Lončarević Ivana S.; Šoronja-Simović Dragana M.; Šereš Zita I.

    2012-01-01

    The aim of this paper was to examine the impact of the manufacturing process on the textural characteristics and sensory properties of milk chocolate. The research was conducted on the samples of chocolate produced in a ball mill during 30, 60 and 90 minutes of refining, each of them being pre-crystallized at 26, 28 and 30°C. A chocolate mass of identical ingredient composition was also produced using a standard manufacturing process at the same pre-crystallization temperatures. Chocola...

  5. Effect of inulin and stevia on some physical properties of chocolate milk.

    Science.gov (United States)

    Homayouni Rad, Aziz; Delshadian, Zohre; Arefhosseini, Seyed Rafi; Alipour, Beitollah; Asghari Jafarabadi, Mohammad

    2012-01-01

    The aim of this study was to assess physical properties of dietetic chocolate milk produced by stevia as a sugar replacer and inulin. Along with having prebiotic effect, inulin can also participate in enhancing textural properties of beverages. Therefore, this novel food will be useful for all people especially for diabetics. This study was carried out in Quality Control Laboratory of Food Science and Technology Department, Health and Nutrition Faculty, Tabriz University of Medical Science, during 2011-2012. The assay was performed on nine treatments with three replications. Sugar was substituted with stevia in two proportions of sucrose to stevia; 50:50 and 0:100. Inulin, in four levels of 0%, 2%, 4% and 6%, was added to the treatments of 50% and 100% stevia. The control sample contained no stevia and no inulin, such as commercial ones. Precipitation amount and viscosity were measured 24 hours after production. Data analyzed by one-way ANOVA, at the significant level of 0.05, using SPSS software ver. 17. Sugar replacement with stevia caused significant increase in precipitation and significant decrease in viscosity (P0.05). The sample containing 50% stevia and 6% inulin had the lowest precipitation while having a non-significantly difference with the control. Conclusion A thickener agent, such as inulin, should be used in the chocolate milk sweetened by stevia to improve physical properties of the product.

  6. Effect of Inulin and Stevia on Some Physical Properties of Chocolate Milk

    Science.gov (United States)

    Homayouni Rad, Aziz; Delshadian, Zohre; Arefhosseini, Seyed Rafi; Alipour, Beitollah; Asghari Jafarabadi, Mohammad

    2012-01-01

    Background: The aim of this study was to assess physical properties of dietetic chocolate milk produced by stevia as a sugar replacer and inulin. Along with having prebiotic effect, inulin can also participate in enhancing textural properties of beverages. Therefore, this novel food will be useful for all people especially for diabetics. Methods: This study was carried out in Quality Control Laboratory of Food Science and Technology Department, Health and Nutrition Faculty, Tabriz University of Medical Science, during 2011-2012. The assay was performed on nine treatments with three replications. Sugar was substituted with stevia in two proportions of sucrose to stevia; 50:50 and 0:100. Inulin, in four levels of 0%, 2%, 4% and 6%, was added to the treatments of 50% and 100% stevia. The control sample contained no stevia and no inulin, such as commercial ones. Precipitation amount and viscosity were measured 24 hours after production. Data analyzed by one-way ANOVA, at the significant level of 0.05, using SPSS software ver. 17. Results: Sugar replacement with stevia caused significant increase in precipitation and significant decrease in viscosity (P0.05). The sample containing 50% stevia and 6% inulin had the lowest precipitation while having a non-significantly difference with the control. Conclusion A thickener agent, such as inulin, should be used in the chocolate milk sweetened by stevia to improve physical properties of the product. PMID:24688916

  7. Rheological, functional and thermo-physical properties of ultrasound treated whey proteins with addition of sucrose or milk powder

    Directory of Open Access Journals (Sweden)

    Anet Režek Jambrak

    2011-03-01

    Full Text Available Ultrasound represents a non-thermal food processing technique and has great potential to be used in the food industry. The objective of this research was to observe ultrasound impact on physical properties of model systems prepared with whey protein isolates (WPI or whey protein concentrates (WPC with or without sucrose or milk powder addition. This kind of systems is often used in milk beverages and milk based products. Model systems with protein and milk powder or sucrose addition were treated with high power ultrasound (HPU probe of 30 kHz frequency for 5 and 10 minutes. After sonication several properties were determined and examined: solubility, emulsifying and foaming properties, rheological and thermophysical properties. Ultrasound treatment showed severe influence on all examined properties, caused by protein denaturation as a consequence of cavitation and microstreaming effects. Ultrasound treatment caused decrease in protein solubility for whey protein isolate and whey protein concentrates model systems, compared to untreated sample. There was statistically significant increase in foam volume of model systems, prepared with sucrose or milk powder and WPI after ultrasound treatment. Statistically significant decrease in emulsion activity and emulsion stability indices was observed for model systems prepared solely with isolates and concentrates. After treatment of whey protein model systems (with or without milk powder or sucrose with 30 kHz ultrasound, the changes in consistency coefficients (k were observed, but there were no significant changes in flow behaviour indices (n. After addition of milk powder or sucrose, statistically significant decrease in initial freezing and melting temperatures was observed due to the ultrasound treatment.

  8. Qualitative Study of Functional Groups and Antioxidant Properties of Soy-Based Beverages Compared to Cow Milk

    Directory of Open Access Journals (Sweden)

    Alessandra Durazzo

    2015-07-01

    Full Text Available Soy-based beverages are a source of high quality proteins and balanced nutrients; they thus represent an alternative to milk in case of allergy to cow milk proteins or intolerance to lactose. In this research, antioxidant properties of soy-based beverages and UHT cow milk were studied. In addition, color parameters, by a quick and non-destructive methodology, were studied in order to verify a possible correlation with antioxidant properties and a qualitative analysis of the major functional groups undertaken by Fourier Transformed Infrared Spectroscopy (FTIR on Attenuated Total Reflectance (ATR was carried out. Extractable and hydrolysable polyphenols were studied in soy-based beverages. However, only the extractable fraction was studied in UHT milk, which was characterized by a small amount of polyphenols. All color parameters showed highly significant differences among soy-based beverages and between soy-based beverages and cow milk. FTIR-ATR spectra of soy-based beverages and cow milk showed several differences in the various regions depending on both the specific contribution of molecular groups and different food items.

  9. Qualitative Study of Functional Groups and Antioxidant Properties of Soy-Based Beverages Compared to Cow Milk.

    Science.gov (United States)

    Durazzo, Alessandra; Gabrielli, Paolo; Manzi, Pamela

    2015-07-15

    Soy-based beverages are a source of high quality proteins and balanced nutrients; they thus represent an alternative to milk in case of allergy to cow milk proteins or intolerance to lactose. In this research, antioxidant properties of soy-based beverages and UHT cow milk were studied. In addition, color parameters, by a quick and non-destructive methodology, were studied in order to verify a possible correlation with antioxidant properties and a qualitative analysis of the major functional groups undertaken by Fourier Transformed Infrared Spectroscopy (FTIR) on Attenuated Total Reflectance (ATR) was carried out. Extractable and hydrolysable polyphenols were studied in soy-based beverages. However, only the extractable fraction was studied in UHT milk, which was characterized by a small amount of polyphenols. All color parameters showed highly significant differences among soy-based beverages and between soy-based beverages and cow milk. FTIR-ATR spectra of soy-based beverages and cow milk showed several differences in the various regions depending on both the specific contribution of molecular groups and different food items.

  10. Qualitative Study of Functional Groups and Antioxidant Properties of Soy-Based Beverages Compared to Cow Milk

    Science.gov (United States)

    Durazzo, Alessandra; Gabrielli, Paolo; Manzi, Pamela

    2015-01-01

    Soy-based beverages are a source of high quality proteins and balanced nutrients; they thus represent an alternative to milk in case of allergy to cow milk proteins or intolerance to lactose. In this research, antioxidant properties of soy-based beverages and UHT cow milk were studied. In addition, color parameters, by a quick and non-destructive methodology, were studied in order to verify a possible correlation with antioxidant properties and a qualitative analysis of the major functional groups undertaken by Fourier Transformed Infrared Spectroscopy (FTIR) on Attenuated Total Reflectance (ATR) was carried out. Extractable and hydrolysable polyphenols were studied in soy-based beverages. However, only the extractable fraction was studied in UHT milk, which was characterized by a small amount of polyphenols. All color parameters showed highly significant differences among soy-based beverages and between soy-based beverages and cow milk. FTIR-ATR spectra of soy-based beverages and cow milk showed several differences in the various regions depending on both the specific contribution of molecular groups and different food items. PMID:26783841

  11. Rheological and physical properties of camel and cow milk gels enriched with phosphate and calcium during acid-induced gelation.

    Science.gov (United States)

    Kamal, Mohammad; Foukani, Mohammed; Karoui, Romdhane

    2017-02-01

    The rheological properties of acid-induced coagulation of camel and cow milk gels following the addition of calcium chloride (CaCl2) and hydrogen phosphate dehydrate (Na2HPO4*2H2O) were investigated using a dynamic low amplitude oscillatory rheology. For a considered condition, the final values of storage modulus (G') and loss modulus (G″) of camel milk gels were significantly lower than those of cow milk gels. The increase of the added CaCl2 levels improved significantly the gelation properties of camel and cow milk gels, since a reduction in the gelation time and an increase in the gel firmness were observed. Following the addition of Na2HPO4*2H2O at 10 and 20 mM, no significant effect on the gelation rate and the firmness of camel milk gels was observed, while, a significant decrease in the gelation rate and firmness were observed for cow milk gels.

  12. Isolation of potential probiotic Lactobacillus oris HMI68 from mother's milk with cholesterol-reducing property.

    Science.gov (United States)

    Anandharaj, Marimuthu; Sivasankari, Balayogan

    2014-08-01

    The objective of this study was to evaluate the probiotic properties of Lactobacillus strains isolated from mother's milk and their effects on cholesterol assimilation. In this study 120 isolates from mother's milk were phenotypically and genotypically characterized. Among these, only 6 predominant strains were identified as Lactobacillus spp. The following parameters were selected as important test variables in model stomach passage survival trials: acid and bile tolerance, antimicrobial activity, antibiotic susceptibility and cholesterol reduction. Results showed that the considerable variation existed among six strains. Moreover, the strain HMI68 is the most acid-tolerant and the HMI28 and HMI74 is the most acid-sensitive of all strains tested. HMI118 did not grow at 0.5% and 1% bile concentration after 5 h but the HMI68 and HMI43 showed some tolerance to such bile concentration. The differences found in the growth rate were not significant (P > 0.05). HMI68 showed resistance to most of the antibiotics as well as antagonistic activity against the tested pathogens. The amount of cholesterol reduction is increased when the media supplemented with bile salts. HMI68 assimilate 61.05 ± 0.05 μg/ml cholesterol with the presence of 0.3% bile salt this could be significantly decreased by 25.41 ± 1.09 μg/ml without bile salt. HMI68 was identified to be Lactobacillus oris HMI68 and 16S rRNA sequence was deposited in the National Center for Biotechnological Information (GenBank). For the first time the cholesterol-reducing property of L. oris isolated from mother's milk were investigated in this study. Therefore the effective L. oris HMI68 strain was regarded as a candidate probiotic.

  13. Human Milk Banking.

    Science.gov (United States)

    Haiden, Nadja; Ziegler, Ekhard E

    2016-01-01

    Human milk banks play an essential role by providing human milk to infants who would otherwise not be able to receive human milk. The largest group of recipients are premature infants who derive very substantial benefits from it. Human milk protects premature infants from necrotizing enterocolitis and from sepsis, two devastating medical conditions. Milk banks collect, screen, store, process, and distribute human milk. Donating women usually nurse their own infants and have a milk supply that exceeds their own infants' needs. Donor women are carefully selected and are screened for HIV-1, HIV-2, human T-cell leukemia virus 1 and 2, hepatitis B, hepatitis C, and syphilis. In the milk bank, handling, storing, processing, pooling, and bacterial screening follow standardized algorithms. Heat treatment of human milk diminishes anti-infective properties, cellular components, growth factors, and nutrients. However, the beneficial effects of donor milk remain significant and donor milk is still highly preferable in comparison to formula.

  14. Bioactive properties and clinical safety of a novel milk protein peptide

    Directory of Open Access Journals (Sweden)

    Chen Helen

    2011-09-01

    Full Text Available Abstract Background Milk protein fractions and peptides have been shown to have bioactive properties. This preliminary study examined the potential mechanisms of action and clinical safety of novel milk protein peptide (MP. Findings A novel MP mixture inhibits the tyrosine kinase activity of epidermal growth factor receptor (EGFR, vascular endothelial growth factor receptor 2 (VEGFR2, and insulin receptor (IR with IC50 of 9.85 μM, 7.7 μM, and 6.18 μM respectively. In vitro, this multi-kinase inhibitor causes apoptosis in HT-29 colon cancer cells, and in a C. elegans worm study, showed a weak but significant increase in lifespan. A six week double-blind, placebo-controlled study involving 73 healthy volunteers demonstrated that the MP mixture is safe to consume orally. All clinical blood markers remained within normal levels and no clinically significant side effects were reported. There was some evidence of improved insulin sensitivity, neutrophil-to-lymphocyte ratio (NLR, and quality of life assessment of role of physical function. Conclusions These data in combination with the observed in vitro anti-cancer properties warrant further clinical studies to investigate this MP mixture as a potential clinical nutrition intervention for improving the quality of life and clinical outcomes in cancer patients. Trial Registration NCT01412658

  15. Designing milk fat to improve healthfulness and functional properties of dairy products: from feeding strategies to a genetic approach

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    Marcello Mele

    2010-01-01

    Full Text Available The present review, in the first part, deals with the most effective feeding strategies applied to dairy ruminants in order to enhance the healthfulness of milk fat. The largest changes in milk fatty acid (FA composition have been obtained either by changing the amounts and the nature of forages in the diets of ruminants, particularly pasture, or by adding plant or marine oils to the diet. Alpine and legume based pastures are associated with high levels of conjugated linoleic acid (CLA, omega-3 FA and with low levels of saturated FA, but further studies are needed with the aim to better explain the effect of some plant species on milk FA composition. Linseed, soybeans safflower and sunflower are the most effective sources of unsaturated plant lipids used to enhance CLA and unsaturated FA content in milk fat. Among animal sources, marine oil is more effective than plant oils for enhancing CLA, vaccenic acid (VA and omega-3 FA in milk fat, especially when fish oil is fed in combination with oil supplements rich in linoleic acid. In the second part of the review the potential contribute of genetic improvement to modifying milk FA composition is discussed. Recent studies have suggested that the genetic improvement of the nutritional quality of milk based on FA profile may be possible. At this aim, genetic parameters of milk FA composition have been estimated in Dutch, US and Italian Holstein populations and in a Belgian multiple breed population of dairy cows. In dairy sheep and goat there is still a lack of knowledge about genetic parameters and correlations of milk FA. The develop of specific selection indexes aimed to improve the nutritional properties of milk could be supported by the new insight about potential candidate genes able to affect a significant quote of the milk FA variability. Increasing evidences indicate the Stearoyl-CoA Desaturase (SCD and Diacylglycerol acyltransferase (DGAT-1 genes as possible sources of FA variation in milk

  16. Functional properties of butter oil made from bovine milk with experimentally altered fat composition.

    Science.gov (United States)

    Ortiz-Gonzalez, G; Jimenez-Flores, R; Bremmer, D R; Clark, J H; DePeters, E J; Schmidt, S J; Drackley, J K

    2007-11-01

    Modification of milk fat composition might be desirable to alter manufacturing characteristics or produce low saturated fat dairy products that more closely meet consumer dietary preferences. The aim of this research was to evaluate functional properties of butter oil obtained from milks with fat composition modified by altering the profile of long-chain fatty acids (FA) absorbed from the small intestine of cows. A control and 5 mixtures of long-chain free FA were infused into the abomasum of lactating dairy cows in a 6 x 6 Latin square design with 21-d periods. Treatments were 1) control (no FA infused), 2) mostly saturated FA (C16:C18 = 0.72), 3) low-linoleic palm FA (C16:C18 = 0.85), 4) palm FA (C16:C18 = 0.72), 5) soy FA (C16:C18 = 0.10), and 6) high-palmitic soy FA (C16:C18 = 0.68). All treatments included meat solubles and Tween 80 as emulsifiers. Solid fat content (from 0 to 40 degrees C), melting point, and force at fracture were determined in butter oil. Milk fat from cows infused with palm FA (treatment 4) exhibited functionality equal to or better than control butter oil. Infusion with palm FA increased amounts of triglyceride (TG) fractions with 48, 52, and 54 carbon numbers but decreased TG with 32, 34, 36, and 42 carbon numbers. Infusion with soy FA increased TG with 26, 38, 40, 52, and 54 carbon numbers but decreased TG with 34, 42, and 46 carbons. Infusion of the mostly saturated FA increased TG with 38, 50, 52, and 54 carbon numbers but decreased TG with 32, 34, and 42 carbon numbers. These TG groups were consistently correlated with functional properties of butter oils from different treatments. The content of palmitic acid is important for maintaining functionality in the presence of increased polyunsaturated FA. The composition of milk fat may be able to be optimized through nutritional manipulation of diets for dairy cows if the optimal composition of FA and TG is defined for a particular dairy product.

  17. Determination of free amino acids in whole-fat Turkish White Brined Cheese produced by animal and microbial milk-clotting enzymes with and without the addition of starter culture

    Directory of Open Access Journals (Sweden)

    Ufuk Eren-Vapur

    2012-12-01

    Full Text Available Coagulating enzymes are essential ingredients for the production of different cheese varieties. The objective of this research was to summarize the effect of rennet type (calf rennet and microbial rennet from Rhizomucor miehei and starter culture on the sensory properties and free amino acids (FAA release during the ripening of Turkish White brined cheese. The concentrations of FAA and sensory properties were similar for cheeses made with both types of coagulant and starter culture. Aminoacids Phe, Leu - Ile, Gln, Val, Pro and Ala were the principal FAAs in the White brined cheeses at all stages of ripening.

  18. Effect of soya milk on nutritive, antioxidative, reological and textural properties of chocolate produced in a ball mill

    Directory of Open Access Journals (Sweden)

    Zarić Danica B.

    2011-01-01

    Full Text Available Chocolate is a complex rheological system in which non-fat cocoa particles and sugar particles are enveloped by crystal matrix of cocoa butter. Physical properties of chocolate depend on ingredient composition, method of production and properly performed pre-crystallization phase. In this work, chocolate was produced in an unconventional way, i.e. in a ball mill applying variable refining time (30, 60 and 90 min and pre-crystallization temperature in chocolate masses (26, 28 and 30⁰C. Two types of chocolate were produced: chocolate with 20% of powdered cow’s milk (R1 and chocolate with 20% of soya milk powder (R2. The quality of chocolate was followed by comparing nutritive composition, 23 polyphenol content, hardness of chocolate, solid triglyceride content (SFC and rheological parameters (Casson yield flow (Pa, Casson viscosity (Pas, the area of the thixotropic loop, elastic modulus and creep curves. The aim of this paper is determining changes caused by replacing cow’s milk with soya milk powder in respect of nutritive, rheological and sensory properties, as well as defining optimal parameters: precrystallization temperature and refining time of soya milk chocolate in order to obtain suitable sensory and physical properties identical to those of milk chocolate mass. The results show that replacing powdered cow’s milk with soya milk powder affects the increase in nutritive value of soya milk chocolate. R2 chocolate mass showed the increase in essential amino acids and fatty acids. This chocolate mass also showed the increase in total polyphenols by 28.1% comparing to R1 chocolate mass. By comparing viscosity, yield stress, shear stress and the area of the thixotropic loop, it can be observed that R1 chocolate mass represents a more organized and simpler system than the mass with soya milk (R2, as it shows lower values for all the above mentioned parameters, regardless of the refining time and pre-crystallization temperature

  19. EFFECT OF PROTEIN SHORTAGE AND CONJUGATED LINOLEIC ACID SUPPLEMENTATION ON QUALITY TRAITS AND MODELLING OF COAGULATION, CURD FIRMING AND SYNERESIS OF HOLSTEIN-FRESIAN MILK

    Directory of Open Access Journals (Sweden)

    Giacomo Cesaro

    2015-09-01

    Full Text Available Aim of the present study was to evaluate the effect of diets with optimal (CP 15% DM or suboptimal (CP 12.3% DM protein content, supplemented (CLA+ or not (CLA- with rumen-protected conjugated linoleic acid (rpCLA on some cheesemaking properties. Twenty Holstein-Fresian mid lactating dairy cows have been reared following a 4×4 Latin square experimental design of 4 periods, 3 weeks each. Individual milk samples, collected during the third week of each period, were analysed for chemical composition, traditional milk coagulation properties (MCP: RCT, k20 and a30 and for recording curd firmness (CF every 15 s over a 90 min period. Data acquired from each sample were used to model CF over time calculating the following parameters: rennet coagulation time (RCTeq, asymptotic potential CF (CFP, CF rate constant (kCF, syneresis rate constant (kCF, maximum CF achieved within 90 min (CFmax and time to CFmax (tmax. Data were analysed using period, diet and group (random as sources of variation. Cows evidenced a strong individual variability within groups and were classified as early (RCT20 min coagulating cows. Dietary protein shortage reduced milk protein and lactose content, while rpCLA supplementation depressed milk fat synthesis. Results showned that traditional MCP parameters were worsened by reduction of dietary protein in the case of milk produced by early coagulating cows, while rpCLA supplementation affected negatively all three traits on all cows. The study of CF model parameters evidenced that CP12 diets have improved CF (CFP and CFmax respect to CP15 when fed to late coagulating cows while worsened CF (CFP and CFmax and reduced kCF when fed to early coagulating cows. The results of the present study underline the complex relationship between dietary fat and protein and their consequences on milk technological properties highlighting the need for further investigations.

  20. Genome-wide association of coagulation properties, curd firmness modeling, protein percentage, and acidity in milk from Brown Swiss cows.

    Science.gov (United States)

    Dadousis, C; Biffani, S; Cipolat-Gotet, C; Nicolazzi, E L; Rossoni, A; Santus, E; Bittante, G; Cecchinato, A

    2016-05-01

    Cheese production is increasing in many countries, and a desire toward genetic selection for milk coagulation properties in dairy cattle breeding exists. However, measurements of individual cheesemaking properties are hampered by high costs and labor, whereas traditional single-point milk coagulation properties (MCP) are sometimes criticized. Nevertheless, new modeling of the entire curd firmness and syneresis process (CFt equation) offers new insight into the cheesemaking process. Moreover, identification of genomic regions regulating milk cheesemaking properties might enhance direct selection of individuals in breeding programs based on cheese ability rather than related milk components. Therefore, the objective of this study was to perform genome-wide association studies to identify genomic regions linked to traditional MCP and new CFt parameters, milk acidity (pH), and milk protein percentage. Milk and DNA samples from 1,043 Italian Brown Swiss cows were used. Milk pH and 3 MCP traits were grouped together to represent the MCP set. Four CFt equation parameters, 2 derived traits, and protein percentage were considered as the second group of traits (CFt set). Animals were genotyped with the Illumina SNP50 BeadChip v.2 (Illumina Inc., San Diego, CA). Multitrait animal models were used to estimate variance components. For genome-wide association studies, the genome-wide association using mixed model and regression-genomic control approach was used. In total, 106 significant marker traits associations and 66 single nucleotide polymorphisms were identified on 12 chromosomes (1, 6, 9, 11, 13, 15, 16, 19, 20, 23, 26, and 28). Sharp peaks were detected at 84 to 88 Mbp on Bos taurus autosome (BTA) 6, with a peak at 87.4 Mbp in the region harboring the casein genes. Evidence of quantitative trait loci at 82.6 and 88.4 Mbp on the same chromosome was found. All chromosomes but BTA6, BTA11, and BTA28 were associated with only one trait. Only BTA6 was in common between MCP

  1. Effects of adsorbents in dairy cow diet on milk quality and cheese-making properties

    OpenAIRE

    Pirlo, G.; C. Tornielli; Abeni, F.; M. P. Cattaneo; L. Migliorati

    2010-01-01

    The use of adsorbents (clinoptilolite+sepiolite) in the diet of cows was evaluated in two trials. A total of 52 Italian Friesian cows were assigned to one of two dietary treatments, control and adsorbent (CON vs. ADS). Individual and bulk milk samples were collected. On individual data, no significant difference was found between treatments in milk yield, milk fat, protein, and lactose concentrations, milk protein yield, pH, and titratable acidity, both in summer and spring. In spring only, t...

  2. Milk Allergy

    Science.gov (United States)

    ... rash, often around the mouth Colic, in babies Milk allergy or milk intolerance? A true milk allergy differs from milk ... Question ingredients when ordering in restaurants. Sources of milk products Obvious sources of allergy-causing milk proteins ...

  3. Thymol nanoemulsified by whey protein-maltodextrin conjugates: the enhanced emulsifying capacity and antilisterial properties in milk by propylene glycol.

    Science.gov (United States)

    Xue, Jia; Davidson, P Michael; Zhong, Qixin

    2013-12-26

    The objective of this research was to enhance the capability of whey protein isolate-maltodextrin conjugates in nanoemulsifying thymol using propylene glycol to improve antilisterial properties in milk. Thymol was predissolved in PG and emulsified in 7% conjugate solution. Transparent dispersions with mean diameters of propylene glycol.

  4. Metabolically Improved Exopolysaccharide Production by Streptococcus thermophilus and Its Influence on the Rheological Properties of Fermented Milk

    OpenAIRE

    Svensson, Malin; Waak, Elisabet; Svensson, Ulla; Rådström, Peter

    2005-01-01

    Altered levels of enzymes in the central carbon metabolism in Streptococcus thermophilus increased the exopolysaccharide (EPS) production 3.3 times over that of the parent strain. The influence of enhanced EPS production on the rheological properties of fermented milk is described for engineered strains of S. thermophilus which produce different levels of EPSs.

  5. Analysis of Some Physio-Chemical Properties of Milk Bush (Thevetia peruviana Seeds

    Directory of Open Access Journals (Sweden)

    O.M. Olatunji

    2011-02-01

    Full Text Available The proximate and some technological properties of milk bush (Thevetia peruviana seeds were investigated. The results obtained showed the following chemical compositions: Moisture content (2.94%, protein (7.44%, oil (57.05%, crude fibre (22.37%, ash (2:24 and carbohydrate by difference (7.76%. In the same vain, mineralogical analysis using an inductively coupled plasma atomic emission spectrometer was conducted. The results obtained showed that magnesium, potassium and sodium were the predominant elements in the seeds. The technological properties studied were unit mass, unit volume, geometric mean, diameter, sphericity, bulk density, true density and porosity with average values of 4.14 g, 4.403.57 mm3, 20.34 mm, 0.67, 657.73 kg/m3, 942.05 kg/m3 and 31%, respectively. Information of these properties could be useful in process machine design. On the other hand, knowledge of the proximate properties is important for nutritional and dietary information.

  6. Effects of adsorbents in dairy cow diet on milk quality and cheese-making properties

    Directory of Open Access Journals (Sweden)

    G. Pirlo

    2010-04-01

    Full Text Available The use of adsorbents (clinoptilolite+sepiolite in the diet of cows was evaluated in two trials. A total of 52 Italian Friesian cows were assigned to one of two dietary treatments, control and adsorbent (CON vs. ADS. Individual and bulk milk samples were collected. On individual data, no significant difference was found between treatments in milk yield, milk fat, protein, and lactose concentrations, milk protein yield, pH, and titratable acidity, both in summer and spring. In spring only, there was a trend (P = 0.07 for a higher milk fat yield and a lower somatic cell number in ADS than in CON group. In summer only, milk clotting time was higher in ADS than in CON group (P < 0.05. On bulk milk, no significant differences in components and technological features were found between the CON and ADS groups. The bulk milk contents in total and soluble Ca were 1100 vs. 1108 mg/kg and 378 vs. 369 mg/kg for CON and ADS respectively, proving to be unaffected by treatment and suggesting a lack of interference by ADS on milk Ca availability for cheese-making process.We concluded that, for a period of 12 weeks, the addition of 1% on DM of the diet for lactating cows of non-nutritional adsorbents does not negatively affect milk yield, milk composition, and cheese-making features.

  7. Degrees of Antioxidant Protection: A 2-Year Study of the Bioactive Properties of Organic Milk in Poland.

    Science.gov (United States)

    Puppel, Kamila; Sakowski, Tomasz; Kuczyńska, Beata; Grodkowski, Grzegorz; Gołębiewski, Marcin; Barszczewski, Jerzy; Wróbel, Barbara; Budziński, Arkadiusz; Kapusta, Aleksandra; Balcerak, Marek

    2017-02-01

    The aim of this study was to determine the nutritional value of organic milk in Poland, investigate the influence of diet on antioxidant capacity and degree of antioxidant protection (DAP), and to examine the effect of season on the bioactive properties of milk from organic farms. From 2014 to 2015, 820 milk samples were collected from 6 organic farms during indoor feeding season (IDS) and pasture feeding season (PS). Pasture feeding season + corn grain (PSCG) cows' daily ration during pasture feeding season was enriched with 4 kg a day of corn to improve dietary energy balance. Milk obtained during PS was found to have a higher fat content, slight but significantly lower protein content compared with milk from IDS. The study showed that the content of monounsaturated fatty acids (MUFA) in milk fat was strongly linked to the concentration of polyunsaturated fatty acids (PUFA) and, to a lesser extent, on the supply of MUFA. The IDS data (concentration of vitamin E, A, and β-carotene) showed the lowest values compared with the PS and PSCG groups. Total antioxidant status (TAS) and DAP showed an increasing trend in organic milk. PSCG was associated with highest level of DAP (9% higher than PS and 79% higher than IDS) and TAS (37% higher than PS and 79% higher than IDS). The results obtained show that supplementation of the basic ration with corn grain improved both TAS and DAP. The higher DAP and TAS value is responsible for product stability, considering the risk factor related to levels of cholesterol-oxide intake in humans.

  8. Multivariate factor analysis of Girgentana goat milk composition

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    Pietro Giaccone

    2010-01-01

    Full Text Available The interpretation of the several variables that contribute to defining milk quality is difficult due to the high degree of  correlation among them. In this case, one of the best methods of statistical processing is factor analysis, which belongs  to the multivariate groups; for our study this particular statistical approach was employed.  A total of 1485 individual goat milk samples from 117 Girgentana goats, were collected fortnightly from January to July,  and analysed for physical and chemical composition, and clotting properties. Milk pH and tritable acidity were within the  normal range for fresh goat milk. Morning milk yield resulted 704 ± 323 g with 3.93 ± 1.23% and 3.48±0.38% for fat  and protein percentages, respectively. The milk urea content was 43.70 ± 8.28 mg/dl. The clotting ability of Girgentana  milk was quite good, with a renneting time equal to 16.96 ± 3.08 minutes, a rate of curd formation of 2.01 ± 1.63 min-  utes and a curd firmness of 25.08 ± 7.67 millimetres.  Factor analysis was performed by applying axis orthogonal rotation (rotation type VARIMAX; the analysis grouped the  milk components into three latent or common factors. The first, which explained 51.2% of the total covariance, was  defined as “slow milks”, because it was linked to r and pH. The second latent factor, which explained 36.2% of the total  covariance, was defined as “milk yield”, because it is positively correlated to the morning milk yield and to the urea con-  tent, whilst negatively correlated to the fat percentage. The third latent factor, which explained 12.6% of the total covari-  ance, was defined as “curd firmness,” because it is linked to protein percentage, a30 and titatrable acidity. With the aim  of evaluating the influence of environmental effects (stage of kidding, parity and type of kidding, factor scores were anal-  ysed with the mixed linear model. Results showed significant effects of the season of

  9. Evaluation of technological properties of Enterococcus faecium CECT 8849, a strain isolated from human milk, for the dairy industry.

    Science.gov (United States)

    Cárdenas, Nivia; Arroyo, Rebeca; Calzada, Javier; Peirotén, Ángela; Medina, Margarita; Rodríguez, Juan Miguel; Fernández, Leonides

    2016-09-01

    In this work, a variety of biochemical properties of Enterococcus faecium CECT 8849, which had been isolated from breast milk, were analyzed. Its acidifying capacity and proteolytic activity were low but, in contrast, remarkable peptidase and esterase activities were observed. Ethanol and 3-hydroxy-2-butanone were the most abundant volatile compounds found in experimental model cheese manufactured with E. faecium CECT 8849. This strain inhibited the growth of several Listeria monocytogenes and Listeria innocua strains in vitro. Enterocin A and B structural genes were detected in E. faecium CECT 8849. Model fermented milk and cheeses were manufactured from milk inoculated or not with L. innocua CECT 8848 (2.5-3 log10 colony forming units mL(-1)) using E. faecium CECT 8849 or Lactococcus lactis ESI 153 as starter cultures. Although E. faecium CECT 8849 controlled Listeria growth in both dairy models, it led to lower reduction in Listeria counts when compared with L. lactis ESI 153.

  10. Effect of Inulin and Stevia on Some Physical Properties of Chocolate Milk

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    Mohammad Asghari Jafarabadi

    2012-07-01

    Full Text Available Background: The aim of this study was to assess physical properties of dietetic chocolate milkproduced by stevia as a sugar replacer and inulin. Along with having prebiotic effect, inulin canalso participate in enhancing textural properties of beverages. Therefore, this novel food will beuseful for all people especially for diabetics.Methods: This study was carried out in Quality Control Laboratory of Food Science and TechnologyDepartment, Health and Nutrition Faculty, Tabriz University of Medical Science, during2011-2012. The assay was performed on nine treatments with three replications. Sugar was substitutedwith stevia in two proportions of sucrose to stevia; 50:50 and 0:100. Inulin, in four levelsof 0%, 2%, 4% and 6%, was added to the treatments of 50% and 100% stevia. The control samplecontained no stevia and no inulin, such as commercial ones. Precipitation amount and viscositywere measured 24 hours after production. Data analyzed by one-way ANOVA, at the significantlevel of 0.05, using SPSS software ver. 17.Results: Sugar replacement with stevia caused significant increase in precipitation and significantdecrease in viscosity (P0.05. The sample containing50% stevia and 6% inulin had the lowest precipitation while having a non-significantlydifference with the control.Conclusion: A thickener agent, such as inulin, should be used in the chocolate milk sweetenedby stevia to improve physical properties of the product.

  11. Comparative evaluation of Bacillus licheniformis 5A5 and Aloe variegata milk-clotting enzymes

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    S. A. Ahmed

    2012-03-01

    Full Text Available The properties of a milk clotting enzyme (MCE produced by bacteria (Bacillus licheniformis 5A5 were investigated and compared to those of rennet extracted from a plant (Aloe variegata. Production of MCE by B. licheniformis 5A5 was better in static than in shaken cultures. Maximum activity (98.3 and 160.3 U/ml of clotting was obtained at 75ºC and 80ºC with bacterial and plant rennet, respectively. In the absence of substrate, the clotting activity of Aloe MCE was found to be less sensitive to heat inactivation up to 80ºC for 75 min, retaining 63.8% of its activity, while bacterial MCE was completely inhibited. CaCl2 stimulated milk clotting activity (MCA up to 2% and 1.5% for bacterial and plant enzymes. NaCl inhibited MCA for both enzymes, even at low concentration (1%. Plant MCE was more sensitive to NaCl at 3% concentration it retained 30.2% of its activity, whereas bacterial MCE retained 64.1%. Increasing skim milk concentration caused a significant increase in MCA up to 6% for both enzymes. Mn2+ stimulated the activity of bacterial and plant enzymes to 158.6 and 177.9%, respectively. EDTA and PMSF increased the activity of plant MCE by 34.4 and 41.1%, respectively, which is higher than those for the bacterial MCE (19.1 and 20.9%. Some natural materials activated MCE, the highest activation of bacterial MCE (128.1% was obtained in the presence of Fenugreek (with acid extraction. However Lupine Giza 1 (with neutral extraction gave the highest activation of plant MCE (137.9%. All extracts from Neem plant increased MCA at range from 105.6% to 136.4%. Plant MCE exhibited much better stability when stored at room temperature (25-30ºC for 30 days, retaining 51.2% of its activity. Bacterial MCE was highly stabile when stored under freezing (-18ºC, retaining 100% of its activity after 30 days. Moreover, bacterial MCE was highly tolerant to repeated freezing and thawing without loss of activity for 8 months.

  12. The influence of various factors on milk clotting time

    Directory of Open Access Journals (Sweden)

    Jovanović Snežana T.

    2002-01-01

    Full Text Available The influence of pH (6.5 and 5.8, amount of added CaCl2 (0, 200 and 400 mg/l, coagulation temperature (30ºC and 35ºC and heat treatment of milk (65ºC/30 min and 87ºC/10 min on the rate of rennet induced milk coagulation (s were investigated. The time (s from rennet addition to onset of gelation (as indicated by the first visible floccules was measured. The milk samples heat-treated at 87ºC/10 min, with 400 mg/l added CaCl2, which were coagulated at 35ºC and pH 5.8, coagulated 23.28-fold faster than the same samples without added CaCl2, which were coagulated at 30ºC and pH 6.5. The results of investigations related to the influence of particular coagulation factors on the coagulation rate of heat-treated milk showed that at pH 6.5 the most pronounced influence was demonstrated by the amount of Ca2+ and temperature of coagulation. At pH 5.8, different amounts of Ca2 and used temperatures of coagulation did not influence coagulation rate regardless of the used heat treatment of milk. The influence of used heat treatment of milk was particularly pronounced during coagulation of samples without added CaCl2 that coagulated at 30ºC and pH 6.5. The used heat treatment of milk practically did not influence the milk coagulation rate at pH 5.8. The greatest influence on milk coagulation rate was showed by pH. This influence was the most marked in coagulation of samples in which the coaggregates were formed, regardless of the amount of added Ca2+ and used coagulation temperatures.

  13. The evolution of chemical and microbiological properties of fresh goat milk cheese during its shelf life.

    Science.gov (United States)

    Masotti, F; Battelli, G; De Noni, I

    2012-09-01

    This study investigated the changes in chemical and microbiological properties of fresh goat milk cheese stored in an open deck refrigerated display cabinet (6 ± 2°C) or in a dark cold room (4 ± 1°C). The effects of partial-vacuum packaging and fluorescent lighting were studied during the cheese shelf life (45 d) and 15 d after. Storage conditions did not affect the pH values (4.3), whereas a slight decrease in moisture (ca. 1%) and in water activity (cheese packaged in the presence of air and stored in a lighted cabinet. The proteolytic trend was also studied through capillary zone electrophoresis by monitoring the degradation of the main casein fractions and the formation of new peptides. In particular, 2 indices, based on peak area ratio of new-formed peptides and casein fractions were related to cheese age. Lipolysis, measured by solid-phase microextraction gas chromatography coupled to mass spectrometry of volatile fatty acids, was unaffected by air or light and did not proceed through storage. As expected, hexanal formed mainly in cheeses stored under light and packaged in air. Evaluation of sensorial quality, performed using a hedonic scale, showed significantly lower scores of cheeses kept under light compared with those kept in the dark, both at 45 and 60 d storage. Overall, the microbiological and chemical results suggested that the shelf life of soft goat milk cheese would be extended from 45 to 60 d. Such conclusion was supported also by the sensory quality evaluation.

  14. Relationship between concentration of health important groups of fatty acids and components and technological properties in cow milk

    Directory of Open Access Journals (Sweden)

    Oto Hanuš

    2010-01-01

    Full Text Available Groups of fatty acids (FAs in milk fat can have positive and negative impact on consumer health. Profile of FAs could be influenced by dairy cow nutrition, breed, milk yield level et cetera. The question is what relationships the FAs could have to quality of milk products? Relationships between FAs and their groups to selected milk indicators were studied in Czech Fleckvieh and Holstein cows (64 bulk milk samples. There were 8 herds in 2-year investigation during winter and summer season. The relationship of saturated FAs (SAFA; 66.22% was significant only to lactose (L content (0.290; P < 0.05. The relationships of monounsaturated FAs (MUFA; 29.21% to milk indicators (MIs were in­si­gni­fi­cant (P > 0.05. The relationships of polyunsaturated FAs (PUFA, beneficial for consumer health; 4.53% to MIs were narrower: fat (T, 0.321; P < 0.05; lactose (L, 0.458; P < 0.01; milk alcohol stability (AL, 0.447; P < 0.01; titration acidity (SH, 0.342; P < 0.01; cheese curd quality (KV, 0.427; P < 0.01; milk fermentationability (JSH, 0.529; P < 0.001, streptococci count in yoghurt (Strepto, 0.316; P < 0.05; total count of noble bacteria in yoghurt (CPMUK, 0.314; P < 0.05; streptococci/lactobacilly ratio (StreptoLacto, 0.356; P < 0.01. The relationships of conjugated linoleic acid (CLA; markedly beneficial for health; 0.68% to MIs were: T (0.379; P < 0.01; L (–0.542; P < 0.001; AL (0.266; P < 0.05; KV (0.411; P < 0.01; Strepto (0.260; P < 0.05; StreptoLacto (0.270; P < 0.05. The higher CLA levels were connected in this way with: higher fat content; lower lactose content; lower alcohol stability; lower streptococci count in yoghurt; lower streptococci/lactobacilly ratio in yoghurt. The PUFA and CLA representation decreased with L increase. Simultaneously some technological milk properties such as alcohol sta­bi­li­ty and fermentationability were slightly improved.

  15. Online evaluation of milk quality according to coagulation properties for its optimal distribution for industrial applications.

    Science.gov (United States)

    Leitner, G; Lavi, Y; Merin, U; Lemberskiy-Kuzin, L; Katz, G

    2011-06-01

    The potential for application of online devices for providing real-time analysis of milk-clotting parameters during milking was studied. The experiment tested established relationships between glandular-level bacterial infection and milk-clotting parameters as evaluated by visible or near-infrared spectroscopy. The parameters yielded by the AfiLab (S.A.E. Afikim, Afikim, Israel) online device were shown to be applicable to derivation of real-time estimations of milk-clotting parameters on the individual cow level. The ability of the AfiLab to perform this task was validated online and statistically by calibration against laboratory testing procedures.

  16. Why does the increase of plasmin worsen the coagulation properties of milk in dairy sheep?

    Directory of Open Access Journals (Sweden)

    G. Enne

    2010-01-01

    Full Text Available The concentrations of whole casein and fat are the factors which play the most important role in determining the cheese-making qualities of milk. Plasmin (PL is the main proteolytic enzyme in milk and has been found to be associated with enhanced casein hydrolysation.

  17. Exposure of fluid milk to LED light negatively affects consumer perception and alters underlying sensory properties.

    Science.gov (United States)

    Martin, Nicole; Carey, Nancy; Murphy, Steven; Kent, David; Bang, Jae; Stubbs, Tim; Wiedmann, Martin; Dando, Robin

    2016-06-01

    Fluid milk consumption per capita in the United States has been steadily declining since the 1940s. Many factors have contributed to this decline, including the increasing consumption of carbonated beverages and bottled water. To meet the challenge of stemming the decline in consumption of fluid milk, the dairy industry must take a systematic approach to identifying and correcting for factors that negatively affect consumers' perception of fluid milk quality. To that end, samples of fluid milk were evaluated to identify factors, with a particular focus on light-emitting diode (LED) light exposure, which negatively affect the perceived sensory quality of milk, and to quantify their relative effect on the consumer's experience. Fluid milk samples were sourced from 3 processing facilities with varying microbial postprocessing contamination patterns based on historical testing. The effect of fat content, light exposure, age, and microbiological content were assayed across 23 samples of fluid milk, via consumer, descriptive sensory, and instrumental analyses. Most notably, light exposure resulted in a broad negative reaction from consumers, more so than samples with microbiological contamination exceeding 20,000 cfu/mL on days approaching code. The predominant implication of the study is that a component of paramount importance in ensuring the success of the dairy industry would be to protect fluid milk from all sources of light exposure, from processing plant to consumer.

  18. Contribution of macrophages to plasmin activity in ewe bulk milk

    Directory of Open Access Journals (Sweden)

    M. Albenzio

    2010-04-01

    Full Text Available A total of 225 bulk sheep milk samples were collected throughout lactation to assess the contribution of macrophages to the regulation of the plasmin/plasminogen system. Samples were analyzed for composition, milk renneting parameters, and for activities of plasmin (PL, plasminogen (PG and plasminogen activators (PA. Isolation of macrophages from milk was performed using a magnetic positive separation; separated cells were lysed and activity of urokinase-PA was determined. PL activity in milk decreased during lactation (P < 0.001. The reduction in plasmin activity recorded in the mid and late lactation milk matched with the increase in PG/PL ratio (P < 0.001. The activity of PA increased throughout lactation (P < 0.001, the highest value being recorded in the late lactation milk.The amount of isolated and concentrated macrophages was higher in early and mid lactation milk than in late lactation milk (P < 0.01. Stage of lactation did not influence the activity of u-PA detected in isolated macrophages. The activity of u-PA associated with macrophages was lower than total PA activity detected in milk. Our results lend support to the hypothesis that in ewe bulk milk from healthy flocks macrophages only slightly contributed to the activation of plasmin/plasminogen system.

  19. Feeding restriction impairs milk yield and physicochemical properties rendering it less suitable for sale

    Directory of Open Access Journals (Sweden)

    Vilmar Fruscalso

    2013-08-01

    Full Text Available Feed shortages are relatively frequent in subtropical pasture-based dairy production systems. The effect of feed restriction on milk yield and physical-chemical traits was evaluated in this study. The experiment was carried out in Brazil's south region. Treatments consisted of control and restricted diet. Six multiparous and six primiparous cows, with 499 ± 47.20 kg body weight (BW, at mid-lactation (188 ± 124 days in milk, producing 19.35 ± 4.10 kg of milk were assigned to two groups, balanced for parity, each group receiving a different sequence of the dietary treatments for 56 days, in a crossover design. Diet nominated as control included 8 kg DM 100 kg BW-1 of Bermuda grass var. Tifton pasture (Cynodon dactylon (L. Pers., 5.00 kg of concentrate and 2.50 kg of Tifton hay per day. The restriction diet consisted of 50 % of the quantity offered in the control diet. Milk production and physicochemical composition were evaluated. Feed restriction reduced milk production by 40 %, body condition score by 5 %, milk magnesium by 14.3 %, lactose by 1.7 %, titratable acidity by 10 % and stability to the ethanol test by 9 % and it tended to increase (7 % milk potassium content. No changes were found for the remaining characteristics. Since feed restriction is quite frequent in Brazil's extensive dairy production systems, our concern is that besides decreased milk production, changes can occur in the physiochemical attributes of the milk, mainly a reduction in the stability to the ethanol test, which may increase the volume of milk rejected by the industry.

  20. Effect of fortification with various types of milk proteins on the rheological properties and permeability of nonfat set yogurt.

    Science.gov (United States)

    Peng, Y; Serra, M; Horne, D S; Lucey, J A

    2009-01-01

    Yogurt base was prepared from reconstituted skim milk powder (SMP) with 2.5% protein and fortified with additional 1% protein (wt/wt) from 4 different milk protein sources: SMP, milk protein isolate (MPI), micellar casein (MC), and sodium caseinate (NaCN). Heat-treated yogurt mixes were fermented at 40 degrees C with a commercial yogurt culture until pH 4.6. During fermentation pH was monitored, and storage modulus (G') and loss tangent (LT) were measured using dynamic oscillatory rheology. Yield stress (sigma(yield)) and permeability of gels were analyzed at pH 4.6. Addition of NaCN significantly reduced buffering capacity of yogurt mix by apparently solubilizing part of the indigenous colloidal calcium phosphate (CCP) in reconstituted SMP. Use of different types of milk protein did not affect pH development except for MC, which had the slowest fermentation due to its very high buffering. NaCN-fortified yogurt had the highest G' and sigma(yield) values at pH 4.6, as well as maximum LT values. Partial removal of CCP by NaCN before fermentation may have increased rearrangements in yogurt gel. Soluble casein molecules in NaCN-fortified milks may have helped to increase G' and LT values of yogurt gels by increasing the number of cross-links between strands. Use of MC increased the CCP content but resulted in low G' and sigma(yield) at pH 4.6, high LT and high permeability. The G' value at pH 4.6 of yogurts increased in the order: SMP = MC yogurt. Practical Application: In yogurt processing, it is common to add additional milk solids to improve viscosity and textural attributes. There are many different types of milk protein powders that could potentially be used for fortification purposes. This study suggests that the type of milk protein used for fortification impacts yogurt properties and sodium caseinate gave the best textural results.

  1. Prediction of bovine milk technological traits from mid-infrared spectroscopy analysis in dairy cows.

    Science.gov (United States)

    Visentin, G; McDermott, A; McParland, S; Berry, D P; Kenny, O A; Brodkorb, A; Fenelon, M A; De Marchi, M

    2015-09-01

    Rapid, cost-effective monitoring of milk technological traits is a significant challenge for dairy industries specialized in cheese manufacturing. The objective of the present study was to investigate the ability of mid-infrared spectroscopy to predict rennet coagulation time, curd-firming time, curd firmness at 30 and 60min after rennet addition, heat coagulation time, casein micelle size, and pH in cow milk samples, and to quantify associations between these milk technological traits and conventional milk quality traits. Samples (n=713) were collected from 605 cows from multiple herds; the samples represented multiple breeds, stages of lactation, parities, and milking times. Reference analyses were undertaken in accordance with standardized methods, and mid-infrared spectra in the range of 900 to 5,000cm(-1) were available for all samples. Prediction models were developed using partial least squares regression, and prediction accuracy was based on both cross and external validation. The proportion of variance explained by the prediction models in external validation was greatest for pH (71%), followed by rennet coagulation time (55%) and milk heat coagulation time (46%). Models to predict curd firmness 60min from rennet addition and casein micelle size, however, were poor, explaining only 25 and 13%, respectively, of the total variance in each trait within external validation. On average, all prediction models tended to be unbiased. The linear regression coefficient of the reference value on the predicted value varied from 0.17 (casein micelle size regression model) to 0.83 (pH regression model) but all differed from 1. The ratio performance deviation of 1.07 (casein micelle size prediction model) to 1.79 (pH prediction model) for all prediction models in the external validation was <2, suggesting that none of the prediction models could be used for analytical purposes. With the exception of casein micelle size and curd firmness at 60min after rennet addition

  2. Flow properties of ice cream mix prepared from palm oil: anhydrous milk fat blends.

    Science.gov (United States)

    Rosnani, A I Wan; Aini, I Nor; Yazid, A M M; Dzulkifly, M H

    2007-05-15

    Ice cream mixes containing 33.4% total solids including 10% fat, 11.1% milk solid-non fat (MSNF), 12% sugar, 0.35% commercial blend of emulsifier/ stabiliser and water were produced. The blending of PO with AMF were conducted at three different ratios 30: 70, 50: 50 and 70: 30, respectively. The experimental ice cream mixes were compared with a control ice cream mix prepared from AMF. The flow properties were measured after ageing at 0, 1, 1.5, 2 and 24 h and determined using a controlled stress rheometer (Haake RS 100). The Power Law and Casson equation was employed to estimate the yield stress of an ice cream mixes. The regression coefficients (r) was represented well by the Casson model (r > 0.99) for all the samples, indicating goodness of fit. The profiles of the consistency coefficients (K(c)) were quite similar for all experimental samples, which could be attributed to the fact that all the samples exhibited similar viscoelastic behaviour. The flow behaviour index (n) of an ice cream mix prepared from PO and their blends with AMF were less then 1.0 (range 0.04-0.08) indicating that they were psuedoplastic fluid. The eta(o) at shear rate 20(-1) indicated higher degree of viscosity in AMF.

  3. Comparing milk yield, chemical properties and somatic cell count from organic and conventional mountain farming systems

    Directory of Open Access Journals (Sweden)

    Marcello Bianchi

    2010-01-01

    Full Text Available A study was undertaken to investigate the effects of farming systems (organic vs. conventional, diet (hay/concentrate vs. pasture and their interaction on milk yield, gross composition and fatty acid (FA profile of dairy cows bred in mountainous areas. For this purpose four dairy farms (two organic and two conventional were chosen in the alpine territory of Aosta Valley (NW Italy; individual milk yield was recorded daily and bulk milk samples were collected monthly from February to September 2007 to cover dietary variations. Higher levels of milk production (P<0.05 and lower milk protein amounts (P<0.01 were observed in the organic farms with respect to the conventional ones, while no significant differences were noticed in milk fat and lactose contents and in somatic cell count. Concerning fatty acids, only small differences were detected between organic and conventional milk and such differences seemed to be related mainly to the stabled period. Diet affected almost all variables studied: pasture feeding provided a significant improvement in the fatty acid composition in both organic and conventional systems leading to lower hypercholesterolemic saturated fatty acids, higher mono- and polyunsaturated fatty acids and conjugated linoleic acid amounts (P<0.001.

  4. Evaluation of probiotic properties of Lactobacillus plantarum WLPL04 isolated from human breast milk.

    Science.gov (United States)

    Jiang, Meiling; Zhang, Fen; Wan, Cuixiang; Xiong, Yonghua; Shah, Nagendra P; Wei, Hua; Tao, Xueying

    2016-03-01

    Lactobacillus plantarum WLPL04, a specific strain isolated from human breast milk, was investigated for its survival capacity (acid and bile salt tolerance, survival in simulated gastrointestinal tract, inhibition of pathogens, antibiotic susceptibility, yield of exopolysaccharides) and probiotic properties (antiadhesion of pathogens, protection from harmful effect of sodium dodecyl sulfate, and antiinflammatory stress on Caco-2 cells). The results showed that Lb. plantarum WLPL04 had broad-spectrum activity against gram-positive strains (Listeria monocytogenes CMCC54007, Bacillus cereus ATCC14579, and Staphylococcus aureus CMCC26003) and gram-negative strains (Pseudomonas aeruginosa MCC10104, Shigella sonnei ATCC25931, Enterobacter sakazakii ATCC29544, Salmonella typhimurium ATCC13311, and Escherichia coli O157:H7). Antibiotic susceptibility tests showed that Lb. plantarum WLPL04 was susceptible to 8 of 14 antibiotics (e.g., erythromycin and nitrofurantoin) and resistant to 6 of 14 antibiotics (e.g., kanamycin and bacitracin). Lactobacillus plantarum WLPL04 was able to survive at pH 2.5 for 3h and at 0.45% bile salt for 12h, suggesting that it can survive well in the gastrointestinal tract. In addition, the exopolysaccharide yield of Lb. plantarum WLPL04 reached 426.73 ± 65.56 mg/L at 24h. With strategies of competition, inhibition, and displacement, Lb. plantarum WLPL04 reduced the adhesion of E. coli O157:H7 (35.51%), Sal. typhimurium ATCC 13311 (8.10%), and Staph. aureus CMCC 26003 (40.30%) on Caco-2 cells by competition, and subsequently by 59.80, 62.50, and 42.60%, respectively, for the 3 pathogens through inhibition, and by 75.23, 39.97, and 52.88%, respectively, through displacement. Lactobacillus plantarum WLPL04 attenuated the acute stress induced by sodium dodecyl sulfate on Caco-2 cells and significantly inhibited the expression of inflammatory cytokines (IL-6, IL-8 and tumor necrosis factor-α) on Caco-2 cells but increased IL-10 expression in vitro

  5. Composition and Some Properties of Spray-Dried Retentates Obtained by the Ultrafiltration of Milk

    OpenAIRE

    Kalab, Miloslav; Caric, Marijana; Zaher, Mansour; Harwalkar, V. R.

    1989-01-01

    Retentates containing 20, 27, and 34% total solids, obtained on commercial scale by the ultrafiltration of milk were spray-dried on laboratory scale using centrifugal atomization and single stage drying with the inlet air temperature of 220 C and the outlet air temperature of 90 C. The protein content in the powders was 31% to 35% compared to 24.8% protein in the control whole-milk powder. Lactose contents were markedly lower in the retentate powders (-10.6%) than in the milk powder (40.4...

  6. Relationship between the metabolite profile and technological properties of bovine milk from two dairy breeds elucidated by NMR-based metabolomics.

    Science.gov (United States)

    Sundekilde, Ulrik Kræmer; Frederiksen, Pernille Dorthea; Clausen, Morten Rahr; Larsen, Lotte Bach; Bertram, Hanne Christine

    2011-07-13

    The aim of the present study was to investigate the relationship between the metabolite profile of milk and important technological properties by using nuclear magnetic resonance (NMR)-based metabolomics. The metabolomics approach was introduced for the metabolic profiling of a set of milk samples from two dairy breeds representing a wide span in coagulation properties. The milk metabolite profiles obtained by proton and carbon NMR spectroscopy could be correlated to breed and, more interestingly, also with the coagulation profile, as established by traditional methods by using principal component analysis (PCA). The metabolites responsible for the separation into breed could mainly be ascribed to carnitine and lactose, whereas the metabolites varying in the samples with respect to coagulation properties included citrate, choline, carnitine, and lactose. The results found in the present study demonstrated a promising potential of NMR-based metabolomics for a rapid analysis and classification of milk samples, both of which are useful for the dairy industry.

  7. Nutritional and biochemical properties of human milk: II. Lipids, micronutrients, and bioactive factors.

    Science.gov (United States)

    Rodriguez-Palmero, M; Koletzko, B; Kunz, C; Jensen, R

    1999-06-01

    Human milk lipids contain preformed LCPUFA in considerable amounts, which serve as precursors for the formation of prostaglandins, prostacyclins, and other lipid mediators, as well as essential components in membrane-rich tissues (such as the brain and the retina), thus affecting functional outcomes. Besides a balanced nutrient composition and a number of conditionally essential nutrients, human milk provides different types and classes of bioactive factors, such as enzymes, hormones, and growth factors, many of which appear to have a role in supporting infantile growth and development. The bioactive agents include antimicrobial factors (e.g., secretory IgA, oligosaccharides, FA); anti-inflammatory agents; transporters (e.g., lactoferrin); and digestive enzymes (e.g., BSSL). Several nonpeptide hormones (thyroid hormones, cortisol, progesterone, pregnanediol, estrogens, and artificial contraceptive) and peptide hormones and growth factors (erythropoietin, hHG, gonadotropin-releasing hormone, epidermal growth factor insulin, insulin-like growth factor-I, nerve growth factor, transforming growth factor-alpha, gastrointestinal regulatory peptides and thyroid-parathyroid hormones) have been isolated and quantitated in human milk. Some of these components are also involved in the maturation of the gastrointestinal tract of the infant. In addition to the passive benefits provided by human milk, several data support the hypothesis that breastfeeding promotes the development of the infant's own immune system, which might confer long-term benefits for the newborn infant. The risk of IDDM, Crohn's disease, and atopic disease is lower in individuals who had been breastfed during infancy. Areas of major interest in human milk research include the study of human milk synthesis and the contributions of dietary composition and maternal metabolism to human milk composition, infantile utilization of human milk components, and the study of bioactive components, such as

  8. Composition and properties of milk and butter from cows fed fish oil.

    Science.gov (United States)

    Baer, R J; Ryali, J; Schingoethe, D J; Kasperson, K M; Donovan, D C; Hippen, A R; Franklin, S T

    2001-02-01

    A control diet and a fish oil diet were fed to 12 multiparous Holstein cows to determine how the incorporation of Menhaden fish oil in the diet would influence the fatty acid composition, especially the conjugated linoleic acid and transvaccenic acid, contents of milk and butter. The control diet consisted of a 50:50 ratio of forage to concentrate, and the fish oil diet consisted of the control diet with 2% (on a dry matter basis) added fish oil. Milk from cows fed the control diet contained higher average concentrations of milk fat (3.37%) compared with milk from cows fed the fish oil diet (2.29%). Milk from cows fed fish oil contained higher concentrations of conjugated linoleic acid, transvaccenic acid, and total unsaturated fatty acids (0.68 and 2.51; 1.42 and 6.28; and 30.47 and 41.71 g/100 g of fat, respectively). Butter made from the fish oil diet milk also had higher concentrations of conjugated linoleic acid, transvaccenic acid, and unsaturated fatty acids. Penetrometer readings indicated fish oil diet butters were softer at 4 and 20 degrees C than the control diet butters. Acid degree values were similar in the fish oil butters compared with the control butters. No significant difference was found in the flavor characteristics of milk and butter from cows fed the control and fish oil diets. Production of milk and butter with increased amounts of conjugated linoleic acid, transvaccenic acid, and other beneficial fatty acids may have a desirable impact on the health of consumers and lead to increased sales.

  9. Milk phospholipids: Organic milk and milk rich in conjugated linoleic acid compared with conventional milk.

    Science.gov (United States)

    Ferreiro, T; Gayoso, L; Rodríguez-Otero, J L

    2015-01-01

    The objective of this study was to compare the phospholipid content of conventional milk with that of organic milk and milk rich in conjugated linoleic acid (CLA). The membrane enclosing the fat globules of milk is composed, in part, of phospholipids, which have properties of interest for the development of so-called functional foods and technologically novel ingredients. They include phosphatidylethanolamine (PE), phosphatidylinositol (PI), phosphatidylcholine (PC), phosphatidylserine (PS), and the sphingophospholipid sphingomyelin (SM). Milk from organically managed cows contains higher levels of vitamins, antioxidants, and unsaturated fatty acids than conventionally produced milk, but we know of no study with analogous comparisons of major phospholipid contents. In addition, the use of polyunsaturated-lipid-rich feed supplement (extruded linseed) has been reported to increase the phospholipid content of milk. Because supplementation with linseed and increased unsaturated fatty acid content are the main dietary modifications used for production of CLA-rich milk, we investigated whether these modifications would lead to this milk having higher phospholipid content. We used HPLC with evaporative light scattering detection to determine PE, PI, PC, PS, and SM contents in 16 samples of organic milk and 8 samples of CLA-rich milk, in each case together with matching reference samples of conventionally produced milk taken on the same days and in the same geographical areas as the organic and CLA-rich samples. Compared with conventional milk and milk fat, organic milk and milk fat had significantly higher levels of all the phospholipids studied. This is attributable to the differences between the 2 systems of milk production, among which the most influential are probably differences in diet and physical exercise. The CLA-rich milk fat had significantly higher levels of PI, PS, and PC than conventional milk fat, which is also attributed to dietary differences: rations for

  10. Short communication: Genetic correlation and heritability of milk coagulation traits within and across lactations in Holstein cows using multiple-lactation random regression animal models.

    Science.gov (United States)

    Pretto, D; Vallas, M; Pärna, E; Tänavots, A; Kiiman, H; Kaart, T

    2014-12-01

    Genetic parameters of milk rennet coagulation time (RCT) and curd firmness (a30) among the first 3 lactations in Holstein cows were estimated. The data set included 39,960 test-day records from 5,216 Estonian Holstein cows (the progeny of 306 sires), which were recorded from April 2005 to May 2010 in 98 herds across the country. A multiple-lactation random regression animal model was used. Individual milk samples from each cow were collected during routine milk recording. These samples were analyzed for milk composition and coagulation traits with intervals of 2 to 3 mo in each lactation (7 to 305 DIM) and from first to third lactation. Mean heritabilities were 0.36, 0.32, and 0.28 for log-transformed RCT [ln(RCT)] and 0.47, 0.40, and 0.62 for a30 for parities 1, 2, and 3, respectively. Mean repeatabilities for ln(RCT) were 0.53, 0.55, and 0.56, but 0.59, 0.61, and 0.68 for a30 for parities 1, 2 and 3, respectively. Mean genetic correlations between ln(RCT) and a30 were -0.19, -0.14, and 0.02 for parities 1, 2, and 3, respectively. Mean genetic correlations were 0.91, 0.79, and 0.99 for ln(RCT), and 0.95, 0.94, and 0.94 for a30 between parities 1 and 2, 1 and 3, and 2 and 3, respectively. Due to these high genetic correlations, we concluded that for a proper genetic evaluation of milk coagulation properties it is sufficient to record RCT and a30 only in the first lactation. Copyright © 2014 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  11. Effects of carbonation on probiotic survivability, physicochemical, and sensory properties of milk-based symbiotic beverages.

    Science.gov (United States)

    Walsh, Helen; Cheng, Jianjun; Guo, Mingruo

    2014-04-01

    Drinkable yogurt is a popular beverage in the United States and there may be a niche for carbonated drinkable yogurt in the functional foods market. Pomegranate (P) and vanilla (V) yogurt beverages were formulated, containing inulin as a prebiotic, along with probiotic bacteria Lactobacillus acidophilus and Bifidobacterium, to produce symbiotic products. These beverages were stabilized with high-methoxyl pectin and whey protein concentrate and compared to samples with approximately 2 volumes of added carbon dioxide (CO2 ). Samples were stored in sealed glass bottles at 4 °C for 9 wk for evaluation of physicochemical and functional properties. Trials were carried out in triplicate and 3 replicates from each trial were analyzed. Physicochemical attributes were analyzed using standard AOAC methods. Survivability of the probiotics and changes in pH and viscosity were measured weekly. Chemical composition of the carbonated beverages was: protein: 1.58 ± 0.05%, 1.59 ± 0.06%, fat: 1.24 ± 0.2%, 1.18 ± 0.11%, total solids: 14.78 ± 0.11%, 14.93 ± 0.05%, ash: 0.49 ± 0.02%, 0.46 ± 0.03%, and carbohydrate (by difference): 11.47 ± 0.12%, 11.69 ± 0.14% for P and V, respectively. Both L. acidophilus and Bifidobacterium were stable and remained above 10(6) CFU/g for both flavors of beverage both with and without carbonation. The new manufacturing technology for these prototypes may have potential for commercialization of carbonated symbiotic milk-based beverages. © 2014 Institute of Food Technologists®

  12. Milk demystified by chemistry.

    Science.gov (United States)

    Obladen, Michael

    2014-09-01

    This article traces the decline of milk from a heavenly elixir to a tradeable food. Early cultures regarded milk not as a simple nutrient, but a living fluid. Heroes and gods were believed to have been nurtured by animals after being abandoned. Character traits were assumed to be transmitted by milk; infantile diseases were attributed to "bad milk", whereas "good milk" was used as a remedy. With chemical methods developed at the end of the 18th century, it became known that human milk was higher in sugar and lower in protein than cow's milk. During the 19th century, "scientific" feeding emerged that meant modifying cow's milk to imitate the proportion of nutrients in human milk. In Boston from 1893, Rotch initiated the "percentage" method, requiring a physician's prescription. In Paris from 1894, Budin sterilized bottled infant milk. In Berlin in 1898, Rubner measured oxygen and energy uptake by calorimetry, prompting feeding by calories, and Czerny introduced regulated feeding by the clock. These activities ignored the emotional dimension of infant nutrition and the anti-infective properties of human milk. They may have also enhanced the decline in breastfeeding, which reached an all-time low in 1971. Milk's demystification made artificial nutrition safer, but paved the way for commercially produced infant formula.

  13. Adhesive properties of predominant bacteria in raw cow's milk to bovine mammary gland epithelial cells.

    Science.gov (United States)

    Hagi, Tatsuro; Sasaki, Keisuke; Aso, Hisashi; Nomura, Masaru

    2013-11-01

    Various bacteria have been found in raw cow's milk, and identifying milk microflora and its functions is critical for maintaining cow health and farm hygiene. Although studies on pathogens and spoilage bacteria in milk have been widely reported, the relationship between milk bacteria, including nonpathogenic bacteria, and the bovine udder is poorly understood. We investigated milk microflora over 1 year using a culture-dependent method and culture-independent analysis by denaturing gradient gel electrophoresis. Among 240 isolates, Lactococcus lactis (81/240) was predominant. The predominant genera were Lactococcus, Stenotrophomonas, Microbacterium, Chryseobacterium, Serratia and Pseudomonas. Among seven strains belonging to these predominant genera, two strains of L. lactis (ssp. lactis and ssp. cremoris) exhibited the highest adherence to bovine mammary gland epithelial cells (BMECs) derived from the bovine udder; 3.4 % of the inoculated bacteria adhered to BMECs. This was followed by Serratia sp. (1.6 %), Microbacterium sp. (0.8 %), Stenotrophomonas maltophilia (0.5 %), Pseudomonas sp. (0.3 %) and Chryseobacterium sp. (0.1 %). The two L. lactis isolates exhibited higher adherence to BMECs than type strains and isolates of various origins.

  14. The impact of manufacturing process on the content of hard triglycerides, hardness and thermal properties of milk chocolate

    Directory of Open Access Journals (Sweden)

    Šoronja-Simović Dragana M.

    2012-01-01

    Full Text Available The rheological and physical properties of the chocolate mass depend on the ingredient composition as well as the manufacturing process. For the purpose of this work, a milk chocolate mass of identical composition and raw materials was manufactured by using the two different manufacturing processes: a standard manufacturing process (SM in five-roller mills including conching, and an unconventional manufacturing process in a ball mill (R1. The quality of both milk chocolate masses was examined by the comparison of thermal (differential scanning calorimetry analysis, textural properties (texture analysis, and the content of hard triglycerides (nuclear magnetic resonance spectroscopy. The main goal of this work was to determine whether chocolate can be produced in a ball mill, using the manufacturing process which results in significant savings, without causing drastic changes to the chocolate physical properties. The new manufacturing process rationalises the standard method by combining two phases, namely conching, and refining into a single one. This results in reduced initial and maintenance costs, as well as costs of workforce and fuel, etc. The results have shown that the new chocolate manufacturing process has a positive impact on texture and thermal properties, while the content of hard triglycerides remains the same.

  15. Electrophoretic and immunological properties of folate-binding protein isolated from bovine milk

    Energy Technology Data Exchange (ETDEWEB)

    Iwai, Kazuo; Tani, Masako; Fushiki, Tohru (Kyoto Univ. (Japan). Faculty of Agriculture)

    1983-07-01

    Changes of the folate-binding protein (FBP) concentration in bovine milk after parturition were investigated. The FBP was highly purified from mature milk by affinity chromatography. The purified FBP showed a single protein band in polyacrylamide gel electrophoresis and was immunologically homogenous in double immunodiffusion. However, in two-dimensional gel electrophoresis, the FBP was separated into several spots in isoelectric focusing in the first dimension, and each spot also showed two molecular weights in SDS-gel electrophoresis in the second dimension. But these FBP molecules were immunologically identical with each other. The neuraminidase treatment obviously diminished the number of isoelectric points of the FBP. Thus, the variety of FBP molecules was at least partially due to the variability of the sialic acid content in the carbohydrate moieties. Moreover, the milk FBP showed species-specificity among mammals immunologically as well as physicochemically.

  16. Properties and stability of butter oil obtained from milk and yoghurt.

    Science.gov (United States)

    Kaya, A

    2000-04-01

    The physical and chemical characteristics and thermal stability of butter oil produced from cow's milk by two different methods were studied. Butter oil samples from cow's milk were made (i) directly from milk and (ii) from yoghurt. Samples were autoxidized at 60, 70 and 80 degrees C in the dark and the reaction monitored by peroxide, thiobarbituric acid and free fatty acid values. Peroxide and thiobarbituric acid values increased as the temperature increased. The increase of the acid value was not significant. The thermal stability was highest in butter oil produced from yoghurt. Oxidative changes compared to hydrolytic changes are of greater significance in the thermal stability of butter oil samples. Arrhenius parameters and activation energies were calculated for the peroxide value data. The percent loss of linolenic acid was about 3 times faster than that of linoleic acid.

  17. The properties and acceptability of fresh cheese produced using the mixture probiotic culture

    Directory of Open Access Journals (Sweden)

    Rajka Božanić

    2002-06-01

    Full Text Available Investigation and production of dairy food with probiotic cultures isincreasing due to its health and nutritive benefits. In this paper the probiotic fresh cheese was produced from skim milk samples with 0,1% fat (A and 1,0% fat (B. Fermentation of skim milk samples was conducted at 40°C by 2% addition of DVS-ABT4 mixture probiotic cultures inoculum with selected bacteria (Lactobacillus acidophilus, Bifidobacterium ssp. and Streptococcus thermophilus and without rennet addition. After milk coagulation (about 7-9 hours, the curd was gently cut and drained overnight. Produced of skim milk cheese samples (A had approximately 23.4% total solids, 1.8% fat in total solids and yield about 24.5% (w/v, while the low fat cheese samples (B had 26.2% total solids, 16.2% fat in total solids and yield about 27.3% (w/v. The skim milk cheeses (A had higher protein and mineral matter content compared to low fat cheeses (B. All samples of probiotic fresh cheese were a like to traditional fresh cheese according to general appearance and consistency. However, they had slightly lower aroma and acidity, expecially skim milk cheese samples (A. Better sensory properties had low fat cheesesamples (B during total time of storage (14 days. Acceptability of probiotic fresh cheese was evalueted by hedonic scale from 63 consumers. Statistic shows that all samples were 100% desirable, but average score for skim milk cheese (A was some lower (x = 7.33 than average score (x = 8.11 for low fat cheese (B. Variance analysis also shows that there is significantly important difference (p= 0,05 between analysed fresh cheese samples

  18. The linear relationship between the proportion of fresh grass in the cow diet, milk fatty acid composition, and butter properties.

    Science.gov (United States)

    Couvreur, S; Hurtaud, C; Lopez, C; Delaby, L; Peyraud, J L

    2006-06-01

    Fresh grass in the cow diet improves the rheological and nutritional properties of butter. However, the relationship between the proportion of fresh grass in the diet and these properties is still unknown. The objective of the study was to determine the relationship between the proportion of fresh grass in the diet and the properties of milk and butter. Four groups of 2 cows were fed 4 isoenergetic diets characterized by increasing amounts of fresh grass (0, 30, 60, and 100% dry matter of forage) according to a Youden square design. Energy levels were similar among all diets. Thus, no effect of mobilization was observed and the results were only due to the proportion of fresh grass in the diet. Milk yield linearly increased with the proportion of fresh grass in the diet (+0.21 kg/d per 10% of grass). Fat yield remained unchanged. Thus, by effect of dilution, increasing the proportion of fresh grass in the diet induced a linear decrease in fat content. Milk fat globule size decreased by 0.29 mum when the proportion of grass reached 30% in the diet. Increasing the proportion of fresh grass in the diet induced a linear increase in unsaturated fatty acids percentages at the expense of saturated fatty acids. Relationships were +0.38, +0.12, +0.05 and -0.69 points/10% of fresh grass in the diet for C18:1 trans-11, C18:2 cis-9,trans-11, C18:3n-3, and C16:0, respectively. These modifications in fatty acid composition, and in particular in the spreadability index, C16:0/C18:1, were responsible for linear decreases in final melting temperature and solid fat content in butter fat, perceived in sensory analysis by a linear decrease in firmness in mouth. The nutritional value of butter was also linearly improved by the proportion of fresh grass in the diet by halving the atherogenicity index.

  19. Probe mobility in native phosphocaseinate suspensions and in a concentrated rennet gel: effect of probe flexibility and size

    NARCIS (Netherlands)

    Salami, S.; Rondeau-Mouro, C.; Duynhoven, van J.P.M.; Mariette, F.

    2013-01-01

    Pulsed field gradient nuclear magnetic resonance and proton nuclear magnetic resonance relaxometry were used to study the self-diffusion coefficients and molecular dynamics of linear (PEGs) and spherical probes (dendrimers) in native phosphocaseinate suspensions and in a concentrated rennet gel. It

  20. Milk fat threshold determination and the effect of milk fat content on consumer preference for fluid milk.

    Science.gov (United States)

    McCarthy, K S; Lopetcharat, K; Drake, M A

    2017-03-01

    Milk consumption in the United States has been in decline since the 1960s. Milk fat plays a critical role in sensory properties of fluid milk. The first objective of this study was to determine the change in percent milk fat needed to produce a detectable or just noticeable difference (JND) to consumers in skim, 1%, 2%, and whole milks. The second objective was to evaluate how milk fat affected consumer preferences for fluid milk. Threshold tests were conducted to determine the JND for each reference milk (skim, 1%, 2%, and whole milk), with a minimum of 60 consumers for each JND. The JND was determined for milks by visual appearance without tasting and tasting without visual cues. Serving temperature effect (4, 8, or 15°C) on tasting JND values were also investigated. The established JND values were then used to conduct ascending forced-choice preference tests with milks. Consumers were assigned to 3 groups based on self-reported milk consumption: skim milk drinkers (n = 59), low-fat milk drinkers (consumed 1% or 2% milk, n = 64), and whole milk drinkers (n = 49). Follow-up interviews were conducted where consumers were asked to taste and explain their preference between milks that showed the most polarization within each consumer segment. Descriptive sensory analysis was performed on the milks used in the follow-up interviews to quantify sensory differences. Visual-only JND were lower than tasting-only JND values. Preference testing revealed 3 distinct preference curves among the consumer segments. Skim milk drinkers preferred skim milk and up to 2% milk fat, but disliked milk higher in fat due to it being "too thick," "too heavy," "flavor and texture like cream," "too fatty," and "looks like half and half." Low-fat milk drinkers preferred 2% milk up to 3.25% (whole milk), but then disliked higher milk fat content. Whole milk drinkers preferred whichever milk was higher in milk fat regardless of how high the fat content was, distinct from skim and low-fat milk

  1. Effect of bee pollen supplement on antimicrobial, chemical, rheological, sensorial properties and probiotic viability of fermented milk beverages

    Directory of Open Access Journals (Sweden)

    Oktay Yerlikaya

    2014-11-01

    Full Text Available In this research, effect of bee pollen supplement on antimicrobial, chemical, rheological, sensorial properties and probiotic viability of fermented milk beverages was studied. Bee pollens were added in the rate of 2.5 mg•mL-1 (B, 5 mg•mL-1 (C, 7.5 mg•mL-1 (D, 10 mg•mL-1 (E, and 20 mg•mL-1 (F. Control sample (A was not supplemented with bee pollen. Control and supplemented milk samples were fermented by a commercial ABT1 starter culture (Chr. Hansen, Hørsholm, Denmark containing Lactobacillus acidophilus La 5, Bifidobacterium animalis subs. lactis Bb 12, and Streptococcus thermophilus. While no antimicrobial impact was observed against L. monocytogenes, S. aureus, P. fluorescens, P. aeruginosa and A. hydrophilia upto 7.5 mg•mL-1 pollen addition, addition between 10 mg•mL-1 to 20 mg•mL-1 resulted in activity, and positive effect only in inhibition rates against bacteria such as S. thyphimurium and E. coli. Bee pollen supplements has shown a positive effect on probiotic viability and occurred on increase apparent viscosity, but their effect on sensorial properties was negative. Furthermore an improvement with increasing concentration of pollen addition that yielded no negative effect on physicochemical properties was detected.

  2. Immunomodulating properties of protein hydrolysates for application in cow's milk allergy

    NARCIS (Netherlands)

    Kiewiet, M. B. G.; Gros, M.; van Neerven, R. J. J.; Faas, M. M.; de Vos, P.

    2015-01-01

    Cow's milk proteins cause allergic symptoms in 2-3% of all infants. In these individuals, the tolerogenic state of the intestinal immune system is broken, which can lead to sensitization against antigens and eventually to allergic responses. Although a true treatment for food allergy is not availabl

  3. Immunomodulating properties of protein hydrolysates for application in cow's milk allergy

    NARCIS (Netherlands)

    Kiewiet, M. B. G.; Gros, M.; van Neerven, R. J. J.; Faas, M. M.; de Vos, P.

    Cow's milk proteins cause allergic symptoms in 2-3% of all infants. In these individuals, the tolerogenic state of the intestinal immune system is broken, which can lead to sensitization against antigens and eventually to allergic responses. Although a true treatment for food allergy is not

  4. Toll-like receptor mediated activation is possibly involved in immunoregulating properties of cow's milk hydrolysates

    NARCIS (Netherlands)

    Kiewiet, M. B. Gea; Dekkers, Renske; Gros, Marjan; van Neerven, R. J. Joost; Groeneveld, Andre; de Vos, Paul; Faas, Marijke M.

    2017-01-01

    Immunomodulating proteins and peptides are formed during the hydrolysis of cow's milk proteins. These proteins are potential ingredients in functional foods used for the management of a range of immune related problems, both in infants and adults. However, the mechanism behind these effects is

  5. [Correlation between the degree of reaction to the rapid mastitis test and the changes in the chemical makeup and properties of bulk cow's milk].

    Science.gov (United States)

    Velov, S; Ivanova, M

    1979-01-01

    Samples of trade cow milk from the milk combine in Stara Zagora were investigated using the quick mastitis tests "Sofia" and "Bernburg". It was established that 38% of the samples studied react positively (+). The samples reacting in a varying degree to the test were investigated for content of total protein, caseine, whey protein, lactose, chlorides, calcium and number of somatic cells. An electrophoretic separation of the caseine fractions was performed on acrylamide gel. The refraction number of milk serum was determined. No composition and property changes were observed in milk samples reacting positively to the test and having a cell content lower than 1 000 000/cm3. Changes of the protein components in favour of whey proteins were evident in milk samples having a positive reaction to the test as well as cell content higher than 1 000 000/cm3. The electrophoretic picture of caseine from milk samples reacting positively to the test and having higher than 1 000 000/cm3 cell content includes all caseine fractions typical for cow milk, but a reduction in the Ls and beta caseine fractions and an increase of kappa- and gamma fractions is observed.

  6. Effect of dextran and dextran sulfate on the structural and rheological properties of model acid milk gels.

    Science.gov (United States)

    Pachekrepapol, U; Horne, D S; Lucey, J A

    2015-05-01

    with 0.5% DS exhibited larger pores than the control gels. This study demonstrated that low concentrations of uncharged DX did not significantly affect the rheological properties of model acid milk gels; high concentrations of DX resulted in earlier gelation, possibly caused by depletion-induced attractions between casein particles, which altered the microstructure and created weaker gels. At pH values gels, which might be due to attractive crosslinking by electrostatic interactions between DS and caseins at pH values below the isoelectric pH of casein (i.e., positively charged casein regions interacted with negatively charged DS molecules).

  7. Influence of feeding Mediterranean food industry by-products and forages to Awassi sheep on physicochemical properties of milk, yoghurt and cheese.

    Science.gov (United States)

    Abbeddou, Souheila; Rischkowsky, Barbara; Hilali, Muhi El-Dine; Hess, Hans Dieter; Kreuzer, Michael

    2011-11-01

    Feeding agro-industrial by-products and unconventional forages, rich in potentially anti-nutritional factors, may influence the quality of the raw milk and the dairy products prepared therefrom. The aim of the present study was to determine side-effects on physicochemical properties of milk, yoghurt and cheese of feeding diets where one third were feeds either rich in lipids (tomato pomace and olive cake) or phenols (olive leaves and lentil straw) or electrolytes (Atriplex leaves). The diets, including a control diet, were designed to be isoenergetic and isonitrogenous. They were fed in amounts of 25 kg dry matter/day per head during 50 days to 6×10 multiparous fat-tailed Awassi ewes. Milk samples were analysed for various physicochemical traits and fatty acid composition on days 0, 24, 36 and 48. Three times, milk pooled by group was processed to yoghurt and non-aged farmer-type cheese, which were analysed for their gross and fatty acid composition and texture, and were subjected to sensory evaluation. Feeding olive cake and tomato pomace reduced milk casein, but increased proportions of monounsaturated fatty acids. There were some variations in minerals among test diets but, contrary to expectations, Atriplex did not increase milk sodium. The nutritional composition of yoghurt and cheese was not varied much by the test feeds, except for some changes in fatty acid profile similar to the milk. Yoghurt firmness declined with all test diets, but texture score tended to be lower only for olive cake and leaf diets relative to control. Cheese firmness was increased by feeding the Atriplex leaf and olive cake diets which was also reflected in the texture scores. No off-flavours were reported. Possible reasons for effects on the dairy products are discussed. In conclusion, the feeds investigated had certain effects on the physicochemical properties of dairy products, but these were neither very systematic nor large thus not prohibiting their use in Mediterranean sheep

  8. Characterization of Lactobacillus from Algerian goat's milk based on phenotypic, 16S rDNA sequencing and their technological properties

    Directory of Open Access Journals (Sweden)

    Ahmed Marroki

    2011-03-01

    Full Text Available Nineteen strains of Lactobacillus isolated from goat's milk from farms in north-west of Algeria were characterized. Isolates were identified by phenotypic, physiological and genotypic methods and some of their important technological properties were studied. Phenotypic characterization was carried out by studying physiological, morphological characteristics and carbohydrate fermentation patterns using API 50 CHL system. Isolates were also characterized by partial 16S rDNA sequencing. Results obtained with phenotypic methods were correlated with the genotypic characterization and 13 isolates were identified as L. plantarum, two isolates as L. rhamnosus and one isolate as L. fermentum. Three isolates identified as L. plantarum by phenotypic characterization were found to be L. pentosus by the genotypic method. A large diversity in technological properties (acid production in skim milk, exopolysaccharide production, aminopeptidase activity, antibacterial activity and antibiotic susceptibility was observed. Based on these results, two strains of L. plantarum (LbMS16 and LbMS21 and one strain of L. rhamnosus (LbMF25 have been tentatively selected for use as starter cultures in the manufacture of artisanal fermented dairy products in Algeria.

  9. Concentration dependent effects of dextran on the physical properties of acid milk gels.

    Science.gov (United States)

    Mende, Susann; Peter, Michaela; Bartels, Karin; Dong, Tingting; Rohm, Harald; Jaros, Doris

    2013-11-06

    The effect of dextran from Leuconostoc mesenteroides (DEX500), added to milk prior to acidification with glucono-δ-lactone (GDL) or Streptococcus thermophilus DSM20259, was studied with respect to polysaccharide concentration. The incorporation of 5-30 g/kg DEX500 significantly affected gelation behavior. Increasing DEX500 concentrations resulted in a linear increase of gel stiffness (GDL gels: R(2)=0.96; microbial acidification: R(2)=0.94; Pgels without polysaccharide. The respective stirred gels depicted a significant reduction in syneresis, which decreased from 30.4% (0 g/kg DEX500) to 22.0% (30 g/kg DEX500) for chemically acidified gels after 1 d of storage. Physical characteristics of DEX500 in aqueous solution were helpful to explain its behavior in the complex system milk.

  10. The principal fucosylated oligosaccharides of human milk exhibit prebiotic properties on cultured infant microbiota

    OpenAIRE

    Yu, Zhuo-Teng; Chen, Ceng; Kling, David E.; Liu, Bo; McCoy, John M.; Merighi, Massimo; Heidtman, Matthew; Newburg, David S.

    2012-01-01

    Breast-fed infant microbiota is typically rich in bifidobacteria. Herein, major human milk oligosaccharides (HMOS) are assessed for their ability to promote the growth of bifidobacteria and to acidify their environment, key features of prebiotics. During in vitro anaerobic fermentation of infant microbiota, supplementation by HMOS significantly decreased the pH even greater than supplementation by fructooligosaccharide (FOS), a prebiotic positive control. HMOS elevated lactate concentrations,...

  11. Lipid complex effect on fatty acid profile and chemical composition of cow milk and cheese.

    Science.gov (United States)

    Bodkowski, R; Czyż, K; Kupczyński, R; Patkowska-Sokoła, B; Nowakowski, P; Wiliczkiewicz, A

    2016-01-01

    The effect of administration of lipid complex (LC) on cow milk and cheese characteristics was studied. Lipid complex was elaborated based on grapeseed oil with synthesized conjugated linoleic acid (CLA) and Atlantic mackerel oil enriched in n-3 fatty acids. The 4-wk experiment was conducted on 30 Polish Holstein Friesian cows. The experimental group cow diet was supplemented with 400 g/d of LC (containing 38% CLA, and eicosapentaenoic acid + docosahexaenoic acid in a relative amount of 36.5%) on a humic-mineral carrier. The chemical composition and fatty acid profile of milk and rennet cheese from raw fresh milk were analyzed. Lipid complex supplementation of the total mixed ration had no effect on milk yield and milk composition, except fat content, which decreased from 4.6 to 4.1%, a 10.9% decrease. Milk from cows treated with LC had greater relative amounts of unsaturated fatty acids, particularly polyunsaturated fatty acids, and lesser relative amounts of saturated fatty acids. Lipid complex addition changed milk fat fatty acid profile: C18:2 cis-9,trans-11 and trans-10,cis-12 isomer (CLA) contents increased by 278 and 233%, respectively, as did eicosapentaenoic acid (C20:5) and docosahexaenoic acid (C22:6) contents. Milk fat fatty acid profile changes were correlated with the modifications in rennet cheese fatty acid profile. Lipid complex supplementation of dairy cows produced considerable changes in the biological value of milk and cheese fat. Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  12. Evaluation of different drying techniques on the nutritional and biofunctional properties of a traditional fermented sheep milk product.

    Science.gov (United States)

    Alu'datt, Muhammad H; Rababah, Taha; Alhamad, Mohammad N; Obaidat, Mohammad M; Gammoh, Sana; Ereifej, Khalil; Al-Ismail, Khaild; Althnaibat, Rami M; Kubow, Stan

    2016-01-01

    The purpose of this study was to evaluate the effect of solar and freeze drying techniques on the physicochemical, nutritional and biofunctional properties of salted or unsalted Jameed from fermented sheep milk product. The highest yield of Jameed was obtained via the salted-solar drying process. As measured by colorimetry, salted freeze-dried Jameed showed improved consumer characteristics in terms of increased lightness and decreased red and yellow color components. When unsalted Jameed was prepared by solar or freeze drying, additional major peptide bands were detected by SDS-PAGE treatments as compared to the solar or freeze drying of the salted Jameed. Use of salt in the preparation of solar dried Jameed also led to the highest ACE inhibitory activities whereas antioxidant activity was lowest in unsalted solar dried Jameed. The study findings indicate that both greater yield and better overall nutritional and biofunctional properties were associated with solar dried salted Jameed.

  13. Continuous fast Fourier transforms cyclic voltammetry as a new approach for investigation of skim milk k-casein proteolysis, a comparative study.

    Science.gov (United States)

    Shayeh, Javad Shabani; Sefidbakht, Yahya; Siadat, Seyed Omid Ranaei; Niknam, Kaveh

    2017-10-01

    Cheese production is relied upon the action of Rennet on the casein micelles of milk. Chymosin assay methods are usually time consuming and offline. Herein, we report a new electrochemical technique for studying the proteolysis of K-casein. The interaction of rennet and its substrate was studied by fast Fourier transform continuous cyclic voltammetry (FFTCCV) based on a determination of k-casein in aqueous solution. FFTCCV technique is a very useful method for studying the enzymatic procedures. Fast response, no need of modified electrodes or complex equipment is some of FFTCCV advantages. Various concentrations of enzyme and substrate were selected and the increase in the appearance of charged species in solution as a result of the addition of rennet was studied. Data obtained using FFTCCV technique were also confirmed by turbidity analysis. The results show that rennet proteolysis activity occurs in much shorter time scales compare with its aggregation. Hence, following the appearance of charged segments as a result of proteolysis could be under consideration as a rapid and online method. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. Some Technological Properties of Lactic Acid Bacteria Isolated from Dahi and Datshi, Naturally Fermented Milk Products of Bhutan

    Science.gov (United States)

    Shangpliang, H. N. J.; Sharma, Sharmila; Rai, Ranjita; Tamang, Jyoti P.

    2017-01-01

    Dahi and datshi are common naturally fermented milk (NFM) products of Bhutan. Population of lactic acid bacteria (LAB) in dahi (pH 3.7) and datshi (pH 5.2) was 1.4 × 107 and 3.9 × 108 cfu/ml, respectively. Based on 16S rRNA gene sequencing isolates of LAB from dahi and datshi were identified as Enterococcus faecalis, E. faecium, Lactococcus lactis subsp. lactis. LAB strains were tested for some technological properties. All LAB strains except E. faecalis CH2:17 caused coagulation of milk at both 30°C for 48 h. Only E. faecium DH4:05 strain was resistant to pH 3. No significant difference (P > 0.05) of viable counts was observed in MRS broth with and without lysozyme. All LAB strains grew well in 0.3% bile showing their ability to tolerate bile salt. None of the LAB strains showed >70% hydrophobicity. This study, being the first of its microbiological analysis of the NFM of Bhutan, has opened up to an extent of research work that gives a new insight to the products. PMID:28203227

  15. Properties of a milk clotting protease isolated from fruits of Bromelia balansae Mez.

    Science.gov (United States)

    Pardo, M F; López, L M; Caffini, N O; Natalucci, C L

    2001-05-01

    Unripe fruit extracts of Bromelia balansae Mez (Bromeliaceae), whose principal endopeptidase is balansain I (isolated for anion exchange chromatography: pI = 5.45, molecular weight = 23192), exhibit a pH profile with a maximum activity around pH 9.0 and are inhibited only by cysteine peptidases inhibitors. The alanine and glutamine derivatives of N-alpha-carbobenzoxy-L-amino acid p-nitrophenyl esters were strongly preferred by the enzyme. Enzymatic hydrolysis of milk and soy proteins yield characteristic patterns at pH 9.0. The N-terminal sequence showed a very high homology (85-90%) with other known Bromeliaceae endopeptidases.

  16. Properties of Folate Binding Protein Purified from Cow’s Milk

    Directory of Open Access Journals (Sweden)

    SUBANDRATE

    2012-09-01

    Full Text Available Folic acid played an important role in the metabolism of the body. To measure the serum folic acid levels could use the folate binding protein (FBP from cow’s milk with a technique analogous to ELISA. The aims of this study were to identify characteristics of FBP from cow’s milk and binding capacity of FBP to folic acid and to purify FBP from other whey protein passed through DEAE-cellulose chromatography column. Each of DEAE-cellulose peaks was passed in affinity chromatography column. FBP was released from affinity column with sodium acetate buffer pH 3.5. The purity of obtained FBP was demonstrated by a single spot in SDS-PAGE analysis and the estimated molecular weight of FBP was around 31 kDa. Our study indicated that 1 mol FBP bound 1 mol folic acid. Alkylation with iodoacetic acid decreased the binding capacity of FBP which suggested the presence of a–SH or imidazol group in its active site. The importance of disulfide bridge was proven by decreasing of folate binding capacity of FBP after -mercaptoethanol treatment. In contrary, the folate binding didn need Ca2+ ion, as indicated by EDTA test which gave the same result as control.

  17. 牛奶蛋白纤维的特性及其应用%Properties and Applications of Milk Protein Fiber

    Institute of Scientific and Technical Information of China (English)

    丁艳梅

    2012-01-01

    文章分析了牛奶蛋白纤维所具有的特性,探讨了其在纺织面料上的广泛应用。%The properties of milk protein fiber were analysed. The applications in textile fabrics were discussed.

  18. Modeling of coagulation, curd firming, and syneresis of milk from Sarda ewes.

    Science.gov (United States)

    Vacca, G M; Pazzola, M; Dettori, M L; Pira, E; Malchiodi, F; Cipolat-Gotet, C; Cecchinato, A; Bittante, G

    2015-04-01

    This study investigated the modeling of curd-firming (CF) over time (CF(t)) of sheep milk. Milk samples from 1,121 Sarda ewes from 23 flocks were analyzed for coagulation properties. Lactodynamographic analyses were conducted for up to 60 min, and 240 CF individual observations from each sample were recorded. Individual sample CFt equation parameters (RCT(eq), rennet coagulation time; CF(P), asymptotic potential value of curd firmness; k(CF), curd-firming instant rate constant; and k(SR), curd syneresis instant rate constant) were estimated, and the derived traits (CF(max), the point at which CF(t) attained its maximum level, and tmax, the time at which CF(max) was attained) were calculated. The incidence of noncoagulating milk samples was 0.4%. The iterative estimation procedure applied to the individual coagulation data showed a small number of not-converged samples (4.4%), which had late coagulation and an almost linear pattern of the ascending part of the CF(t) curve that caused a high value of CF(P), a low value of k(CF), and a high value of k(SR). Converged samples were classified on the basis of their CF(t) curves into no-k(SR) (18.0%), low-k(SR) (72.6%), and high-k(SR) (4.5%). A CF(t) that was growing continuously because of the lack of the syneresis process characterized the no-k(SR) samples. The high-k(SR) samples had a much larger CFP, a smaller k(CF), and an anticipation of tmax, whereas the low-k(SR) samples had a fast k(CF) and a slower k(SR). The part of the average CF(t) curves that showed an increase was similar among the 3 different syneretic groups, whereas the part that decreased was different because of the expulsion of whey from the curd. The traditional milk coagulation properties recorded within 30 min were not able to detect any appreciable differences among the 4 groups of coagulating samples, which could lead to a large underestimation of the maximum CF of all samples (if predicted by a30), with the exception of the no-k(SR) samples

  19. Milk yield, composition and qua­li­ty of organic milk of ewes crossbreeds of Lacaune, East Friesian and Improved Wallachian during lactation

    Directory of Open Access Journals (Sweden)

    Michaela Pokorná

    2009-01-01

    Full Text Available Evaluation of milk yield, composition and quality of organic milk of crossbreeds of Lacaune (L, East Friesian (EF and Improved Wallachian (IW, (n = 10, L 50 EF 43.75 IW 6.25 during lactation was carried out on organic farm in Valašská Bystřice in 2007. All sheep were on the third lactation and during study they were reared on permanent pasture. The stage of lactation (SL had a highly significant effect on milk yield (MY and contents of total solids (TS, fat (F, protein (P, casein (C, lactose (L and urea (U. The SL had also a highly significant effect on pH and titrable acidity (TA, whereas on rennet clotting time (RCT the SL had a significant effect. On the other hand the SL had not a significant effect on somatic cell counts (SCC and rennet curd quality (RCQ. The highest contents of TS, F and C were found at the end of the lactation, whereas their lowest contents were found on the 120th day. Between the second and the last sampling the lactose content decreased. The content of U and RCT were the most variable indicators whithin the frame of our study. On the other hand SCCs were, during the whole lactation, very well-balanced and relatively low. Between pH and SCC was found positive correlation. TA gradually increased and RCT gradually prolonged with advanced lactation.

  20. Simultaneous Effects of Total Solids Content, Milk Base, Heat Treatment Temperature and Sample Temperature on the Rheological Properties of Plain Stirred Yogurt

    Directory of Open Access Journals (Sweden)

    Attilio Converti

    2006-01-01

    Full Text Available Response surface methodology was used to establish a relationship between total solids content, milk base, heat treatment temperature, and sample temperature, and consistency index, flow behaviour index, and apparent viscosity of plain stirred yogurts. Statistical treatments resulted in developments of mathematical models. All samples presented shear thinning fluid behaviour. The increase of the content of total solids (9.3–22.7 % and milk base heat treatment temperature (81.6–98.4 °C resulted in a significant increase in consistency index and a decrease in flow behaviour index. Increase in the sample temperature (1.6–18.4 °C caused a decrease in consistency index and increase in flow behaviour index. Apparent viscosity was directly related to the content of total solids. Rheological properties of yogurt were highly dependent on the content of total solids in milk.

  1. PARTIAL PURIFICATION OF MILK-CLOTTING ENZYME FROM THE SEEDS OF MORINGA OLEIFERA

    Directory of Open Access Journals (Sweden)

    Amna E. Tajalsir

    2014-08-01

    Full Text Available The aim of the present study was to search for milk clotting substitute from different parts (flowers, seeds, stem, leaves, ripe and unripe fruits of Moringa oleifera. The samples were blended and extracted using different types of extracting solutions. The most reliable, quick and efficient enzyme extracting solution was found to be 5% NaCl in 100 mM sodium acetate buffer, pH 5.0, which was used throughout the study. The milk clotting activity was only observed in the seeds extract while the other parts were either deficient or has very low milk clotting activity. Thus, the moringa seeds were used as source of milk clotting enzyme. The extracted proteins were fractionated with ammonium sulfate at concentration of 20, 30, 40, 50 and 60 %. Highest milk clotting activity was observed in the 20 % fraction. This fraction was assumed to contain the clotting enzymes and characterized for its heating stability (30 – 90°C and optimum temperature (30 – 90°C. The results demonstrated that moringa seeds milk clotting enzyme is stable up to 50°C with an optimum milk clotting activity of 70°C. The high ratio of milk-clotting to proteolytic activity of the partially purified enzyme indicates the potential of this enzyme as suitable rennet substitute in dairy industry. However, further study is needed to completely purify and characterize this promising milk clotting enzyme from moringa seeds.

  2. Effects of temperature and supplementation with skim milk powder on microbial and proteolytic properties during storage of cottage cheese.

    Science.gov (United States)

    Oh, Nam Su; Lee, Hyun Ah; Myung, Jae Hee; Joung, Jae Yeon; Lee, Ji Young; Shin, Yong Kook; Baick, Seung Chun

    2014-06-28

    The aim of this study was to determine the effects of temperature and supplementation with skim milk powder (SMP) on the microbial and proteolytic properties during the storage of cottage cheese. Cottage cheese was manufactured using skim milk with 2% SMP and without SMP as the control, and then stored at 5°C or 12°C during 28 days. The chemical composition of the cottage cheese and the survival of the cheese microbiota containing starter lactic acid bacteria (SLAB) and non-starter culture lactic acid bacteria (NSLAB) were evaluated. In addition, changes in the concentration of lactose and lactic acid were analyzed, and proteolysis was evaluated through the measurement of acid soluble nitrogen (ASN) and nonprotein nitrogen (NPN), as well as electrophoresis profile analysis. The counts of SLAB and NSLAB increased through the addition of SMP and with a higher storage temperature (12°C), which coincided with the results of the lactose decrease and lactic acid production. Collaborating with these microbial changes, of the end of storage for 28 days, the level of ASN in samples at 12°C was higher than those at 5°C. The NPN content was also progressively increased in all samples stored at 12°C. Taken together, the rate of SLAB and NSLAB proliferation during storage at 12°C was higher than at 5°C, and consequently it led to increased proteolysis in the cottage cheese during storage. However, it was relatively less affected by SMP fortification. These findings indicated that the storage temperature is the important factor for the quality of commercial cottage cheese.

  3. Properties and stability of oil-in-water emulsions stabilized by coconut skim milk proteins.

    Science.gov (United States)

    Onsaard, Ekasit; Vittayanont, Manee; Srigam, Sukoncheun; McClements, D Julian

    2005-07-13

    Protein fractions were isolated from coconut: coconut skim milk protein isolate (CSPI) and coconut skim milk protein concentrate (CSPC). The ability of these proteins to form and stabilize oil-in-water emulsions was compared with that of whey protein isolate (WPI). The solubility of the proteins in CSPI, CSPC, and WPI was determined in aqueous solutions containing 0, 100, and 200 mM NaCl from pH 3 to 8. In the absence of salt, the minimum protein solubility occurred between pH 4 and 5 for CSPI and CSPC and around pH 5 for WPI. In the presence of salt (100 and 200 mM NaCl), all proteins had a higher solubility than in distilled water. Corn oil-in-water emulsions (10 wt %) with relatively small droplet diameters (d32 approximately 0.46, 1.0, and 0.5 mum for CSPI, CSPC, and WPI, respectively) could be produced using 0.2 wt % protein fraction. Emulsions were prepared with different pH values (3-8), salt concentrations (0-500 mM NaCl), and thermal treatments (30-90 degrees C for 30 min), and the mean particle diameter, particle size distribution, zeta-potential, and creaming stability were measured. Considerable droplet flocculation occurred in the emulsions near the isoelectric point of the proteins: CSPI, pH approximately 4.0; CSPC, pH approximately 4.5; WPI, pH approximately 4.8. Emulsions with monomodal particle size distributions, small mean droplet diameters, and good creaming stability could be produced at pH 7 for CSPI and WPI, whereas CSPC produced bimodal distributions. The CSPI and WPI emulsions remained relatively stable to droplet aggregation and creaming at NaCl concentrations of < or =50 and < or =100 mM, respectively. In the absence salt, the CSPI and WPI emulsions were also stable to thermal treatments at < or =80 and < or =90 degrees C for 30 min, respectively. These results suggest that CSPI may be suitable for use as an emulsifier in the food industry.

  4. Herpesviruses and breast milk

    Directory of Open Access Journals (Sweden)

    C. Pietrasanta

    2014-06-01

    Full Text Available Breast milk has always been the best source of nourishment for newborns. However, breast milk can carry a risk of infection, as it can be contaminated with bacterial or viral pathogens. This paper reviews the risk of acquisition of varicella-zoster virus (VZV and cytomegalovirus (CMV, herpesviruses frequently detected in breastfeeding mothers, via breast milk, focusing on the clinical consequences of this transmission and the possible strategies for preventing it. Maternal VZV infections are conditions during which breastfeeding may be temporarily contraindicated, but expressed breast milk should always be given to the infant. CMV infection acquired through breast milk rarely causes disease in healthy term newborns; an increased risk of CMV disease has been documented in preterm infants. However, the American Academy of Pediatrics (AAP does not regard maternal CMV seropositivity as a contraindication to breastfeeding; according to the AAP, in newborns weighing less than 1500 g, the decision should be taken after weighing the benefits of breast milk against the risk of transmission of infection. The real efficacy of the different methods of inactivating CMV in breast milk should be compared in controlled clinical trials, rigorously examining the negative consequences that each of these methods can have on the immunological and nutritional properties of the milk itself, with a view to establish the best risk-benefit ratio of these strategies before they are recommended for use in clinical practice.

  5. Preparation of dietary fiber powder from tiger nut (Cyperus esculentus) milk ("Horchata") byproducts and its physicochemical properties.

    Science.gov (United States)

    Sánchez-Zapata, Elena; Fuentes-Zaragoza, Evangélica; Fernández-López, Juana; Sendra, Esther; Sayas, Estrella; Navarro, Casilda; Pérez-Alvarez, Jose Angel

    2009-09-09

    "Horchata" is a vegetable milk obtained from tiger nuts. The solid waste from horchata production was analyzed for physicochemical and microbial properties, aiming to determine its potential use as a fiber source for the food industry. The solid waste contains a high proportion of total dietary fiber (59.71 g/100 g), composed mainly of insoluble dietary fiber (99.8%). It has a high water-holding capacity (8.01 g/g) and oil-holding capacity (6.92 g/g) and a low water absorption (1.79 g/g) and water adsorption (0.23 g/g) capacities, in comparison with other dietary fiber sources. The emulsifying ability was 70.33 mL/100 mL, and the wastes showed high emulsion stability (100 mL/100 mL). The physicochemical properties indicate that tiger nut byproducts are rich in fiber and may be considered a potential ingredient in a healthy diet. However, the microbial quality was poor, meaning that it must be pasteurized prior to its addition to any food product.

  6. Effect of concentration, homogenization and stabilizing salts on heat stability and rheological properties of cow skim milk ultrafiltered retentate.

    Science.gov (United States)

    Meena, Ganga Sahay; Singh, Ashish Kumar; Borad, Sanket; Panjagari, Narender Raju

    2016-11-01

    Ultrafiltration (UF) of skimmed milk altered the composition of UF retentate and decreased the heat stability. Heat stability further reduced upon its subsequent homogenization or diafiltration. Poor heat stability of UF retentate restricts its processing at elevated temperatures. Therefore, this study was aimed to investigate the effect of protein concentration, homogenization and addition of stabilizing salts on the heat stability and rheological properties of UF retentates. Changes in the heat stability of fivefold homogenized UF retentate (5× HUFR) was studied in the pH range of 6.1-7.0. Disodium phosphate and trisodium citrate significantly increased the heat coagulation time (HCT) from 1.45 min (pH 6.41) to 120 min (at pH 6.5, 6.6, 7.0) and 80 min (pH 6.6), respectively. Significant reduction in ζ-potential of UF retentates was observed with an increase in calcium and reduction in pH during UF process. Rheological behaviour of retentates above threefold concentration exhibited Herschel-Bulkley behavior with linear increase in flow behavior index (n). Changes in the viscosity of the homogenized retentates were measured at the respective pH of maximum heat stability as a function of temperature (20-80 °C). Promising approaches that might improve the heat stability, solubility and other functional properties of protein rich powders have been discussed in this article.

  7. 内蒙古双峰驼乳及乳制品中乳杆菌的分离及其%STUDIES ON BIOLOGICAL PROPERTIES OF LACTOBACILLUS FROM TOW-HUMPED CAMEL MILK AND ITS MILK PRODUCTS IN INNER MONGOLIAR

    Institute of Scientific and Technical Information of China (English)

    孟和毕力格; 敖墩格日勒; 李少英; 王锂韫; 乌尼

    2001-01-01

    16 strains of lactobacillus were isolated from 11 samples oftow-humped camel milk and its milk products.Their biological properties were studied.According to the morphological character,physiological and biochemical reaction,they respectively belonged to 3 genus 6 species:5 strains of Lactobacillus casei subsp.casei,4 strains of Lactobacillus plantarum and strain of Lactobacillus delbruekii subsp.lactis. Most of strains belong to homofermentation.But AZ41-1 and AZ44-1 strains belong to heterofermentation Lactobacillus.Most strains had weak acid-producing abilities to solidify milk.%本实验主要对11份双峰骆驼乳样品进行了乳酸杆菌的分离和生物学特性的研究。将分离到的16株革兰氏阳性、过氧化氢酶试验阴性杆菌,分别鉴定为Lactobacilluscasei subsp. casei(5株)、Lactobacillus plantarum(4株)和Lactobacillus delbruekii subsp.lactis等同型发酵乳杆菌和2株异型发酵乳杆菌(AZ41-1和AZ44-1)。多数菌株为15℃生长良好,以中温性菌株占优势。脱脂乳中产酸量较低。

  8. Milk Thistle

    Science.gov (United States)

    ... R S T U V W X Y Z Milk Thistle Share: On This Page Background How Much ... Foster This fact sheet provides basic information about milk thistle—common names, usefulness and safety, and resources ...

  9. Milk Allergy

    Science.gov (United States)

    ... Events Blog Media Shop Alerts Donate About Food Allergies Home About Food Allergy Food Allergy Basics Facts ... Registration Create Your Own Events Educational Events Milk Allergy Allergy to cow’s milk is the most common ...

  10. Purification of bovine milk lactoperoxidase and investigation of antibacterial properties at different thiocyanate mediated.

    Science.gov (United States)

    Uğuz, M T; Ozdemir, H

    2005-01-01

    Bovine lactoperoxidase (LPO) was purified with amberlite CG 50 H+ resin, CM sephadex C-50 ion-exchange chromatography, and sephadex G-100 gel filtration chromatography from skim milk. The activity of lactoperoxidase was measured by using 2.2-azino-bis (3-ethylbenzthiazoline-6 sulfonic acid) diammonium salt (ABTS) as a choromogenic substrate at pH 6.0. Purification degree for the purified enzyme was controlled with SDS-PAGE and Rz value (A412/A280). Rz value for the purified LPO was 0.8. Km value at pH 6.0 at 20 degrees C for the LPO was 0.20 mM. Vmax value was 7.87 micromol/ml min at pH 6.0 at 20 degrees C. Bovine LPO showed high antibacterial activity in 100 mM thiocyanate--100 mM H2O2 medium for some pathogenic bacteria, such as Aeromonas hydrophila ATCC 7966, Micrococcus luteus LA 2971, Mycobacterium smegmatis RUT, Bacillus subtilis IMG 22, Pseudomonas pyocyanea, Bacillus subtilis var. niger ATCC 10, Pseudomonas aeruginosa ATCC 27853, Enterococcus faecalis ATCC 15753, Bacillus brevis FMC3, Klebsiella pneumoniae FMC 5, Corynebacterium xerosis UC 9165, Bacillus cereus EU, Bacillus megaterium NRS, Yersinia enterocolytica, Listeria monocytogenes scoot A, Bacillus megaterium EU, Bacillus megaterium DSM32, Klebsiella oxytocica, Staphylococcus aerogenes, Streptococcus faecalis, Mycobacterium smegmatis CCM 2067 and compared with well known antibacterial substances such as penicilline, ampicilline, amoxicillin-clavulanate and ceftriaxon. The LPO--100 mM thiocyanate--100 mM H2O2 system was purposed as an effective agent against many of the diseases causing organisms in human and animals.

  11. Preterm milk.

    Science.gov (United States)

    Baum, J D

    1980-03-01

    This editorial addresses the question of how best to feed the low birth weight infant. A study by Atkinson et al. on the composition of preterm mothers' milk found the nitrogen concentration in preterm milk to be considerably higher than in term milk. Preterm milk may be uniquely suited to the growth requirements of preterm infants. With the exception of calcium and phosphorus, preterm milk fits the requirements for preterm infant growth. Because of the difficulties of sustaining lactation without the infant sucking at the breast, partly due to the mother's motivation in the face of all the difficulties of having a baby in a Special Care Baby Unit, and partly due to the associated socioeconomic disadvantages, it is not possible for all mothers who deliver preterm babies to sustain their lactation. The composition of preterm milk should be used as a guide for the preparation of a human milk formula built from human milk products from a milk bank. The development of a human milk formula must take into account variations in the absorption of nutrients in low birth weight infants which may be affected by the processing of the milk, and variations in fat absorption in preterm infants which occur even when they are fed their mothers' fresh unprocessed milk.

  12. Characterization of partially purified milk-clotting enzyme from sunflower (Helianthus annuus) seeds.

    Science.gov (United States)

    Nasr, Assia I A M; Mohamed Ahmed, Isam A; Hamid, Omer I A

    2016-09-01

    This study was aimed to extract milk-clotting enzyme from sunflower seeds and to determine its potentiality for manufacturing white soft cheese from cows and goats milk. The seeds were blended and extracted using two types of buffers and milk-clotting and proteolytic activities were evaluated. The enzyme was partially purified using ammonium sulfate fractionation techniques. Results indicated that sunflower seeds extracted with 5% NaCl in 50 mmol/L acetate buffer, pH 5.0, had the highest milk-clotting activity (MCA) and lowest coagulation time compared to that extracted with only acetate buffer (pH 5.0). Ammonium sulfate at 30-50% saturation purified the enzyme to 4.3 folds with MCA of 241.0 U/mL and final enzyme yield of 10.9%. The partially purified enzyme was characterized by SDS-PAGE that showed two bands with molecular weight of 120 and 62 kDa. When compared with other plant enzymes, the partially purified sunflower enzyme was found to have higher milk-clotting activity and lower proteolytic activity. Also, both milk sources and enzyme types significantly affected the cheese yield and curd formation time. The cheese made from cow milk using sunflower enzyme had higher yield compared to that obtained using commercial rennet, whereas the opposite was observed when using goat milk.

  13. 莎能奶山羊羊乳凝乳特性初探%Pilot Study on Coagulating Property of Saanen Goat Milk

    Institute of Scientific and Technical Information of China (English)

    周强; 刘蒙佳; 张富新

    2012-01-01

    The effects of calcium concentration, pH value, temperature and chelating agents on coagulating property of Saanen goat milk were pilot studied. The results showed that the coagulation time of goat milk was increased with the increase in pH (6.4 ~ 7.2) values, and decreased with the addition of Ca2+ (0.01 -0.06 g/L). The coagulation time of goat milk was increased markedly by the addition of chelating agents (Na2HPO4, Na5P3O10, Na4P2O7, Na3C6H5O7·2H2O). Different chelating agents had different efficiency to coagulating property of goat milk, and Na5P3O10 had the highest efficiency to the coagulating time of goat milk.%初探了Ca2+浓度、pH值、温度、螯合剂对莎能奶山羊羊乳凝乳特性的影响.结果表明:在pH值为6.4 ~7.2范围内,随着pH值的增大,羊乳的凝乳时间延长;在0.01 ~0.06 g/L范围内,随着Ca2+浓度的增加,羊乳的凝乳时间逐渐缩短;随着螯合剂(磷酸氢二钠、三聚磷酸钠、焦磷酸钠和柠檬酸钠)添加量的增加,羊乳的凝乳时间延长,其中以三聚磷酸钠对羊乳凝乳时间的影响最大.

  14. Bayesian regression models outperform partial least squares methods for predicting milk components and technological properties using infrared spectral data.

    Science.gov (United States)

    Ferragina, A; de los Campos, G; Vazquez, A I; Cecchinato, A; Bittante, G

    2015-11-01

    The aim of this study was to assess the performance of Bayesian models commonly used for genomic selection to predict "difficult-to-predict" dairy traits, such as milk fatty acid (FA) expressed as percentage of total fatty acids, and technological properties, such as fresh cheese yield and protein recovery, using Fourier-transform infrared (FTIR) spectral data. Our main hypothesis was that Bayesian models that can estimate shrinkage and perform variable selection may improve our ability to predict FA traits and technological traits above and beyond what can be achieved using the current calibration models (e.g., partial least squares, PLS). To this end, we assessed a series of Bayesian methods and compared their prediction performance with that of PLS. The comparison between models was done using the same sets of data (i.e., same samples, same variability, same spectral treatment) for each trait. Data consisted of 1,264 individual milk samples collected from Brown Swiss cows for which gas chromatographic FA composition, milk coagulation properties, and cheese-yield traits were available. For each sample, 2 spectra in the infrared region from 5,011 to 925 cm(-1) were available and averaged before data analysis. Three Bayesian models: Bayesian ridge regression (Bayes RR), Bayes A, and Bayes B, and 2 reference models: PLS and modified PLS (MPLS) procedures, were used to calibrate equations for each of the traits. The Bayesian models used were implemented in the R package BGLR (http://cran.r-project.org/web/packages/BGLR/index.html), whereas the PLS and MPLS were those implemented in the WinISI II software (Infrasoft International LLC, State College, PA). Prediction accuracy was estimated for each trait and model using 25 replicates of a training-testing validation procedure. Compared with PLS, which is currently the most widely used calibration method, MPLS and the 3 Bayesian methods showed significantly greater prediction accuracy. Accuracy increased in moving from

  15. Isoelectric focusing and ELISA for detecting adulteration of donkey milk with cow milk.

    Science.gov (United States)

    Pizzano, Rosa; Salimei, Elisabetta

    2014-06-25

    Donkey milk has been recently revalued intensely due to its nutritional properties. Moreover, donkey milk has been proposed as an effective alternative food for some infants with cow milk allergy. Two fast analytical methods were proposed to detect the fraudulent practice of blending cow milk to donkey milk. Detection of cow αs1-casein bands along the profiles of experimental donkey-cow milk mixtures analyzed by isoelectric focusing was adequate to estimate cow milk used as adulterant of donkey milk starting from 5% (v/v). An ELISA-based method using the antipeptide antibodies raised against the 1-28 sequence stretch of cow β-casein was also developed for an accurate definition of composition of donkey-cow milk mixtures. The presence of cow milk at levels as low as 0.5% (v/v) was detected in donkey-cow milk mixtures prepared at laboratory scale and assayed by ELISA.

  16. Effect of enzymatic hydrolysis of starch on pasting, rheological and viscoelastic properties of milk-barnyard millet (Echinochloa frumentacea) blends meant for spray drying.

    Science.gov (United States)

    Kumar, P Arun; Pushpadass, Heartwin A; Franklin, Magdaline Eljeeva Emerald; Simha, H V Vikram; Nath, B Surendra

    2016-10-01

    The influence of enzymatic hydrolysis of starch on the pasting properties of barnyard millet was studied using a rheometer. The effects of blending hydrolyzed barnyard millet wort with milk at different ratios (0:1, 1:1, 1:1.5 and 1:2) on flow and viscoelastic behavior were investigated. From the pasting curves, it was evident that enzymatically-hydrolyzed starch did not exhibit typical pasting characteristics expected of normal starch. The Herschel-Bulkley model fitted well to the flow behaviour data, with coefficient of determination (R(2)) ranging from 0.942 to 0.988. All milk-wort blends demonstrated varying degree of shear thinning with flow behavior index (n) ranging from 0.252 to 0.647. Stress-strain data revealed that 1:1 blend of milk to wort had the highest storage modulus (7.09-20.06Pa) and an elastically-dominant behavior (phase angle <45°) over the tested frequency range. The crossover point of G' and G" shifted to higher frequencies with increasing wort content. From the flow and viscoelastic behavior, it was concluded that the 1:1 blend of milk to wort would have least phase separation and better flowability during spray drying.

  17. Shiga Toxin-Producing Escherichia coli Isolated from Bovine Mastitic Milk: Serogroups, Virulence Factors, and Antibiotic Resistance Properties

    Science.gov (United States)

    Momtaz, Hassan; Safarpoor Dehkordi, Farhad; Taktaz, Taghi; Rezvani, Amir; Yarali, Sajad

    2012-01-01

    The aim of this study was to detect the virulence factors, serogroups, and antibiotic resistance properties of Shiga toxin-producing Escherichia coli, by using 268 bovine mastitic milk samples which were diagnosed using California Mastitis Test. After E. coli identification, PCR assays were developed for detection of different virulence genes, serogroups, and antibiotic resistance genes of Escherichia coli. The antibiotic resistance pattern was studied using disk diffusion method. Out of 268 samples, 73 (27.23%) were positive for Escherichia coli, and, out of 73 positive samples, 15 (20.54%) were O26 and 11 (15.06%) were O157 so they were the highest while O111 was not detected in any sample so it was the lowest serogroup. Out of 73 STEC strains, 11 (15.06%) and 36 (49.31%) were EHEC and AEEC, respectively. All of the EHEC strains had stx1, eaeA, and ehly, virulence genes, while in AEEC strains stx1 had the highest prevalence (77.77%), followed by eaeA (55.55%). Totally, aadA1 (65.95%) had the highest while blaSHV (6.38%) had the lowest prevalence of antibiotic resistance genes. The disk diffusion method showed that the STEC strains had the highest resistance to penicillin (100%), followed by tetracycline (57.44%), while resistance to cephalothin (6.38%) was the lowest. PMID:23213293

  18. Saccharomyces cerevisiae from Brazilian kefir-fermented milk: An in vitro evaluation of probiotic properties.

    Science.gov (United States)

    Lima, Meire Dos Santos Falcão de; Souza, Karoline Mirella Soares de; Albuquerque, Wendell Wagner Campos; Teixeira, José António Couto; Cavalcanti, Maria Taciana Holanda; Porto, Ana Lúcia Figueiredo

    2017-09-01

    The therapeutic use of probiotics for supporting the antibiotic action against gastrointestinal disorders is a current trend and emerging applications have gained popularity because of their support for various microbiological activities in digestive processes. Microorganisms isolated from kefir with great probiotic properties, in addition to high resistance to harsh environmental conditions, have been widely researched. Administration of probiotic yeasts offers a number of advantages, when compared to bacteria, because of particular characteristics as their larger cell size. In the present study, 28 strains of Saccharomyces cerevisiae were isolated, after in vitro digestion of kefir-fermented milk, and identified by molecular based approaches. A screening was performed to determine important quality requirements for probiotics including: antagonistic and antioxidant activities, β-galactosidase synthesis, autoaggregation, surface hydrophobicity and adhesion to epithelial cells. The results showed strains: with antagonistic activity against microbial pathogens such as Klebsiella pneumoniae, Pseudomonas aeruginosa, Staphylococcus aureus, Bacillus subtilis; able to produce β-galactosidase; with antioxidant activity levels higher than 90%; with hydrophobicity activity and autoaggregation ability (evaluated by adhesion test, where all the strains presented adhesion to mice ileal epithelial cells). These findings are relevant and the strains are recommended for further in vivo studies as well as for potential therapeutic applications. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. MELT AND THERMAL PROPERTIES OF INJECTION MOLDED MILK-PROTEIN-BASED BIOPOLYMERS

    Science.gov (United States)

    The need to reduce the use of petroleum products has focused research efforts on using agricultural materials as substitutes for petroleum based plastics. Dairy proteins, such as whey and casein, offer significant property advantages over other agricultural materials and are compatible with biosynt...

  20. [Milk fever].

    Science.gov (United States)

    Dumont, M

    1989-05-01

    Infectious complications following delivery were, in the past, attributed to "milk fever": these were milk congestion, milk deposits, rancid milk, etc., that were held responsible. The milk was reabsorbed into the blood of the patient and settled in the peritoneum ("milk peritonitis"), in the broad ligaments (pelvic abscess), in the thighs (phlebitis) and also in the breasts (breast abscess). This belief, originated by Aristotle, was accepted by excellent authors like Andre Levret (1703-1780), one of the most famous French obstetricians and Nicolas Puzos, at the same time. More recently, authors alluded to it and blamed "milk fever" for being at the origin of dramatic pictures which they described in their novels, like Victor Hugo and Guy de Maupassant, for instance.

  1. The heat treatment and the gelation are strong determinants of the kinetics of milk proteins digestion and of the peripheral availability of amino acids.

    Science.gov (United States)

    Barbé, Florence; Ménard, Olivia; Le Gouar, Yann; Buffière, Caroline; Famelart, Marie-Hélène; Laroche, Béatrice; Le Feunteun, Steven; Dupont, Didier; Rémond, Didier

    2013-02-15

    This study aimed to determine the kinetics of milk protein digestion and amino acid absorption after ingestion of four dairy matrices by six minipigs: unheated or heated skim milk and corresponding rennet gels. Digestive contents and plasma samples were collected over a 7 h-period after meal ingestion. Gelation of milk slowed down the outflow of the meal from the stomach and the subsequent absorption of amino acids, and decreased their bioavailability in peripheral blood. The gelled rennet matrices also led to low levels of milk proteins at the duodenum. Caseins and β-lactoglobulin, respectively, were sensitive and resistant to hydrolysis in the stomach with the unheated matrices, but showed similar digestion with the heated matrices, with a heat-induced susceptibility to hydrolysis for β-lactoglobulin. These results suggest a significant influence of the meal microstructure (resulting from heat treatment) and macrostructure (resulting from gelation process) on the different steps of milk proteins digestion. Copyright © 2012 Elsevier Ltd. All rights reserved.

  2. Crude glycerol as glycogenic precursor in feed; effects on milk coagulation properties and metabolic profiles of dairy cows.

    Science.gov (United States)

    Harzia, Hedi; Kilk, Kalle; Ariko, Tiia; Kass, Marko; Soomets, Ursel; Jõudu, Ivi; Kaart, Tanel; Arney, David; Kärt, Olav; Ots, Meelis

    2013-05-01

    As grain prices rise, the search for alternative glycogenic precursors in animal feed becomes increasingly important, and this study was conducted to determine if the replacement of starch with glycerol, as an alternative glycogenic precursor, affects the milk metabolic profile and milk coagulation ability, and therefore the quality of the milk. Eight primiparous mid-lactation Holstein cows were fed during a replicated 4 × 4 Latin square trial with four different isoenergetic rations: (1) control (T0) fed a total mixed ration (TMR) with barley meal; (2) group T1, decreased barley content, replaced isoenergetically with 1 kg crude glycerol; (3) group T2, the barley meal was replaced with 2 kg of crude glycerol; and (4) group T3 the barley meal was replaced with 3 kg of crude glycerol. Rumen, blood and milk samples were collected at the end of every 21-d treatment period. Rumen samples were analysed for proportion of total volatile fatty acid (VFA), blood samples for insulin and glucose, and milk for metabolites (e.g. citric-acid cycle compounds). The change in glycogenic precursors had a positive effect on rumen VFA proportions; the proportion of propionic acid increased (P < 0.001). Milk protein (P < 0.001) and curd firmness (P < 0.001) both increased. The increase in milk protein concentration may have been due to an increase in microbial protein. Regarding the milk metabolic profiles, different signals were positively associated with coagulation ability and change in the diet. Based on this study, changing the glycogenic precursor in animal diet in this way is possible, and may have no immediate deleterious consequences on milk quality or cow health. Indeed, there is evidence for benefits from this substitution.

  3. Cow's milk and goat's milk.

    Science.gov (United States)

    Turck, Dominique

    2013-01-01

    Cow's milk is increasingly suggested to play a role in the development of chronic degenerative, non-communicable disorders whereas goat's milk is advocated as having several health benefits. Cow's milk is a rich and cheap source of protein and calcium, and a valuable food for bone health. Despite their high content in saturated fats, consumption of full-fat dairy products does not seem to cause significant changes in cardiovascular disease risk variables. Early introduction of cow's milk is a strong negative determinant of iron status. Unmodified cow's milk does not meet nutritional requirements of infants although it is acceptable to add small volumes of cow's milk to complementary foods. Cow's milk protein allergy has a prevalence ranging from 2 to 7%, and the age of recovery is usually around 2-3 years. The evidence linking cow's milk intake to a later risk of type 1 diabetes or chronic degenerative, non-communicable disorders (obesity, metabolic syndrome, type 2 diabetes, hypertension) is not convincing. Milk probably protects against colorectal cancer, diets high in calcium are a probable cause of prostate cancer, and there is limited evidence suggesting that high consumption of milk and dairy products increases the risk for prostate cancer. There is no evidence to support the use of a cow's milk-free diet as a primary treatment for individuals with autistic spectrum disorders. Unmodified goat's milk is not suitable for infants because of the high protein and minerals content and of a low folate content. Goat's milk has no clear nutritional advantage over cow's milk and is not less allergenic. The European Food Safety Authority recently stated that proteins from goat's milk can be suitable as a protein source for infant and follow-on formula, provided the final product complies with the compositional criteria laid down in Directive 2006/141/EC.

  4. Purification and separation of multiple forms of lactophorin from bovine milk whey and their immunological and electrophoretic properties.

    Science.gov (United States)

    Kanno, C

    1989-04-01

    Lactophorin is designated as a glycoprotein, which is present in bovine milk whey and reacts to the antiserum of the soluble glycoprotein of bovine milk fat globule membrane. The lactophorin was purified by DEAE-cellulose (pH 7.7), Sephadex G-100, and then Bio Gel A-15m from the component-3 fraction of the proteose-peptone fraction of bovine milk whey. The purified lactophorin was separated into seven components by DEAE-cellulose chromatography at pH 8.6. The seven components (LP-1 to -7) of lactophorin were almost homogeneous, but the respective bands were somewhat broad and varied in mobilities on disc electrophoresis. The seven lactophorin components fused completely to the antisoluble glycoprotein of milk fat globule membrane on double immunodiffusion but showed different mobilities of precipitation lines on immunoelectrophoresis. The results indicated that lactophorin consisted of multiple forms but had a common set of antigenic determinant groups against anti-soluble glycoprotein.

  5. Designing milk fat to improve healthfulness and functional properties of dairy products: from feeding strategies to a genetic approach

    OpenAIRE

    2010-01-01

    The present review, in the first part, deals with the most effective feeding strategies applied to dairy ruminants in order to enhance the healthfulness of milk fat. The largest changes in milk fatty acid (FA) composition have been obtained either by changing the amounts and the nature of forages in the diets of ruminants, particularly pasture, or by adding plant or marine oils to the diet. Alpine and legume based pastures are associated with high levels of conjugated linoleic acid (CLA), ome...

  6. Effects of duodenal infusions of palmitic, stearic, or oleic acids on milk composition and physical properties of butter.

    Science.gov (United States)

    Enjalbert, F; Nicot, M C; Bayourthe, C; Moncoulon, R

    2000-07-01

    Four dairy cows fitted with a duodenal cannula were used in a 4 x 4 Latin square design to investigate the effects of daily duodenal infusion of 500 g of fatty acids (containing mainly C16:0, C18:0, or cis-C18:1) on fecal concentrations of fatty acids, fatty acid profiles of milk fat, and solid fat content of butter. Fecal concentrations of C16:0 and especially of C18:0 were increased by duodenal infusion. Infusion with C16:0 increased the proportion of C16:0 in milk fat and delayed softening of butter when the temperature rose. Infusion with C18:0 resulted only in a slight increase of C18:0 proportion in milk fat and did not significantly affect solid fat in butter between -10 and 30 degrees C. With the infusion of cis-C18:1, the proportion of cis-C18:1 in milk fat was more than twice that of control, to the detriment of C16:0. Butter contained low proportion of solid fat, even at low temperatures. Increasing C16:0 or cis-C18:1 in milk fatty acid via duodenal infusion can be used to study their specific effects on butter characteristics, but, because of a low transfer from infusion to milk, this method is less efficient with C18:0.

  7. Effects of different forms of canola oil fatty acids plus canola meal on milk composition and physical properties of butter.

    Science.gov (United States)

    Bayourthe, C; Enjalbert, F; Moncoulon, R

    2000-04-01

    Twenty multiparous Holstein cows were used in a 16-wk trial. A block of 10 cows received a control diet, based on corn silage, and the other block of 10 cows successively received four diets with 1) an extruded blend of canola meal and canola seeds, 2) canola meal and whole canola seeds, 3) canola meal and ground canola seeds, or 4) canola meal and calcium salts of canola oil fatty acids. Canola fat represented about 2% of dietary dry matter. Compared to control cows, treated cows had similar dry matter intake, milk production, and daily milk output of true protein or fat. Protein contents of milk was decreased by all treatments, with a lower effect of extruded or whole canola seeds. Milk fat contents was lowered by all treatments, extruded seeds and calcium salts resulting in most important effects. All treatments lowered the percentage of fatty acids with 12 to 16 carbons in milk fat, increased C18:0 and cis-C18:1 percentages, and the proportion of liquid fat in butter between 0 and 12 degrees C. Calcium salts and, to a lesser extent extruded seeds, resulted in most important improvements of milk fatty acid profile and butter softness, whereas whole seeds had low effects.

  8. Chemical species in cheese and their origin in milk components.

    Science.gov (United States)

    Hill, A R

    1995-01-01

    Cheese making is the process of concentrating milk fat and protein by separation from water and soluble components. The objective of the cheese maker is to maximize yield efficiency by optimum utilization of each milk component while not compromising cheese quality. Cheese yielding potential of milk may be increased by selective breeding for specific protein genotypes, especially the BB variant of both kappa-casein and beta-lactoglobulin. Milk fat is included in cheese by occlusion into the protein coagulum. Participation of casein in both lactic and rennet coagulation is nearly complete so that casein losses to the whey occur mainly during cutting and the early stages of cooking. In lactic cheese, excepting cottage cheese, it is possible to eliminate losses of fines by centrifugal or membrane separation of curd. In heat-acid precipitated varieties protein recovery is increased by inclusion of whey proteins but fat recovery is very dependent on coagulation conditions. In ripened cheese obtaining the correct basic structure and composition is critical to texture and flavour development during curing.

  9. Nutritional composition, antioxidant properties, and toxicology evaluation of the sclerotium of Tiger Milk Mushroom Lignosus tigris cultivar E.

    Science.gov (United States)

    Kong, Boon-Hong; Tan, Nget-Hong; Fung, Shin-Yee; Pailoor, Jayalakshmi; Tan, Chon-Seng; Ng, Szu-Ting

    2016-02-01

    The Tiger Milk Mushroom (Lignosus spp.) is an important medicinal mushroom in Southeast Asia and has been consumed frequently by the natives as a cure for a variety of illnesses. In this study, we hypothesized that Lignosus tigris (cultivar E) sclerotium may contain high nutritional value and antioxidant properties, is nontoxic and a potential candidate as a dietary supplement. The chemical and amino acid compositions of the sclerotium were evaluated and antioxidant activities of the sclerotial extracts were assessed using ferric reducing antioxidant power; 1,1-diphenyl-2-picrylhydrazyl; and superoxide anion radical scavenging assays. Acute toxicity of the L. tigris E sclerotium was assessed using a rat model study. The sclerotium was found to be rich in carbohydrate, protein, and dietary fibers with small amounts of fat, calories, and sugar. The amino acid composition of the protein contains all essential amino acids, with a protein score of 47. The sclerotial extracts contain phenolics, terpenoids, and glucan. The ferric reducing antioxidant power values of the various sclerotial extracts (hot water, cold water, and methanol) ranged from 0.008 to 0.015 mmol min(-1) g(-1) extract, while the 1,1-diphenyl-2-picrylhydrazyl and superoxide anion radical scavenging activities ranged from 0.11 to 0.13, and -2.81 to 9.613 mmol Trolox equivalents g(-1) extract, respectively. Acute toxicity assessment indicated that L. tigris E sclerotial powder was not toxic at the dose of 2000 mg kg(-1). In conclusion, L. tigris E sclerotium has the potential to be developed into a functional food and nutraceutical.

  10. The effects of sucrose on the mechanical properties of acid milk proteins-kappa-carrageenan gels

    Directory of Open Access Journals (Sweden)

    E. Sabadini

    2006-03-01

    Full Text Available Mechanical properties have been widely correlated with textural characteristics to determine the interactions during the process formation of dairy gel. These interactions are strongly affected by process conditions and system composition. In the present study, the rheological of acid-induced protein dairy gels with (2(7-3 and without (2(6-2 sucrose and subjected to small and large deformations were studied using an experimental design. The independent variables were the sodium caseinate, whey protein concentrate (WPC, carrageenan and sucrose concentrations as well as stirring speed and heat treatment time and temperature. Mechanical deformation tests were performed at 0.1, 1, 5, and 9 mm/s up to 80% of initial height. A heavy dependence of rupture stress on increasing crosshead speed and the formation of harder gels with the addition of sucrose were observed. Moreover the elastic and viscous moduli, obtained by fitting the Maxwell model to stress relaxation data, increased with increasing addition of sucrose. These results can be explained by preferential hydration of the casein with sucrose, causing an induction of casein-polysaccharide and casein-casein interactions.

  11. Binding of aflatoxin M1 to different protein fractions in ovine and caprine milk.

    Science.gov (United States)

    Barbiroli, A; Bonomi, F; Benedetti, S; Mannino, S; Monti, L; Cattaneo, T; Iametti, S

    2007-02-01

    The affinity of aflatoxin M1 toward the main milk protein fractions in ewe and goat milk was investigated by using an ELISA. This study took into account the possible effects of common dairy processes such as ultrafiltration, acidic or rennet curding, and production of ricotta from acidic or rennet whey. Treatments that allowed the separation of casein from whey proteins under conditions that do not alter the physical or chemical status of the proteins (such as ultracentrifugation) were used as a reference. None of the treatments used in typical dairy processes caused significant release of the toxin, in spite of the relevant changes they induced in the interactions among proteins. Only the combined heat and acidic treatment used for production of ricotta cheese altered the structure of whey proteins to the point where they lost their ability to bind the toxin. This study also showed that, regardless of the physical state of the sample, a commercial electronic nose device, in combination with appropriate statistical tools, was able to discriminate among different levels of sample contamination.

  12. Effect of feeding goats with distilled and non-distilled thyme leaves (Thymus zygis subp. gracilis) on milk and cheese properties.

    Science.gov (United States)

    Boutoial, Khalid; García, Victor; Rovira, Silvia; Ferrandini, Eduardo; Abdelkhalek, Oussama; López, María Belén

    2013-11-01

    The aim of this study was to evaluate the effect of feeding goats with distilled and non-distilled thyme leaves (Thymus zygis subsp. gracilis) on the physicochemical composition and technological properties of pasteurised goat milk, and on the physicochemical composition, phenolic content, oxidative stability, microbiology, sensory and texture profile of Murcia al Vino goat cheese. One group of goats was fed the basal diet (control), the second and third groups were fed with different levels of distilled (10 and 20%) or non-distilled (3·75 and 7·5%) thyme leaves. Goat milk physicochemical composition was significantly affected by the substitution of 7·5% of basal goat diet with non-distilled thyme leaves (increase in fat, protein, dry matter and PUFA content), while goat milk clotting time was increased significantly by the introduction of 20% distilled thyme leaves, which reduces its technological suitability. Microbiology, sensory and texture profiles were not affected by the introduction of distilled thyme leaves. The introduction of distilled and non-distilled thyme leaves as an alternative feed to diet can lead to an inhibition of lipids oxidation. The introduction of distilled and non-distilled thyme leaves into goat's diet can be successfully adopted as a strategy to reduce feeding costs and to take advantage of the waste from the production of essential oils, minimising waste removing costs and the environmental impact.

  13. Biochemical and milk-clotting properties and mapping of catalytic subsites of an extracellular aspartic peptidase from basidiomycete fungus Phanerochaete chrysosporium.

    Science.gov (United States)

    da Silva, Ronivaldo Rodrigues; de Oliveira, Lilian Caroline Gonçalves; Juliano, Maria Aparecida; Juliano, Luiz; de Oliveira, Arthur H C; Rosa, Jose C; Cabral, Hamilton

    2017-06-15

    For a long time, proteolytic enzymes have been employed as key tools of industrial processes, especially in the dairy industry. In the present work, we used Phanerochaete chrysosporium for biochemical characterization and analysis of catalytic specificity of an aspartic peptidase. Our results revealed an aspartic peptidase with molecular mass ∼38kDa, maximal activity at pH 4.5 and 50°C, and stability above 80% in the pH range of 3-8 and temperature up to 55°C for 1h. In a milk-clotting assay, this peptidase showed maximal milk clotting activity at 60-65°C and maintenance of enzymatic activity above 80% in the presence of 20mM CaCl2. In a specificity assay, we observed stronger restriction of catalysis at the S1 subsite, with a preference for lysine, arginine, leucine, tyrosine, and phenylalanine residues. The restricted proteolysis and milk-clotting potential are attractive properties for the use in cheese production. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. Immobilization of Bacillus licheniformis 5A1 milk-clotting enzyme and characterization of its enzyme properties

    OpenAIRE

    Esawy, Mona A.; Combet-Blanc, Yannick

    2006-01-01

    Milk-clotting enzyme from Bacillus licheniformis 5A1 was immobilized on Amberlite IR-120 by ionic binding. Almost all the enzyme activity was retained on the support. The immobilized milk-clotting enzyme was repeatedly used to produce cheese in a batch reactor. The production of cheese was repeated 5 times with no loss of activity. The specific activity calculated on a bound-protein basis was slightly higher than that of free enzyme. The free and immobilized enzyme were highly tolerant to rep...

  15. Effects of Pleurotus eryngii polysaccharides on bacterial growth, texture properties, proteolytic capacity, and angiotensin-I-converting enzyme-inhibitory activities of fermented milk.

    Science.gov (United States)

    Li, Siqian; Shah, Nagendra P

    2015-05-01

    Pleurotus eryngii is one of the most favored oyster mushrooms and contains various beneficial bioactive compounds. Polysaccharide extracted from P. eryngii (PEPS) was added as a natural-source ingredient to milk before fermentation, and the effects of additional PEPS on fermented milk were investigated in this study. The PEPS were extracted and added to reconstituted skim milk (12%, wt/vol) at 0.5, 0.25, and 0.125% (wt/vol) and fermented by a non-exopolysaccharide-producing strain, Streptococcus thermophilus Australian Starter Culture Collection (ASCC) 1303 (ST 1303), or an exopolysaccharide-producing Strep. thermophilus ASCC 1275 (ST 1275). Bacterial growth, texture properties, microstructure, proteolytic capacity, and angiotensin-I-converting enzyme-inhibitory activities of fermented milk (FM) were determined during refrigerated storage at 4°C for 21d. Viable counts of starter bacteria in FM with 0.5% PEPS added were the highest. Changes in pH were consistent with changes in titratable acidities for all samples. The FM samples with added PEPS showed denser protein aggregates containing larger serum pores in confocal micrographs compared with those without PEPS at d 0 and 21during refrigerated storage. The values for spontaneous whey separation of FM with added PEPS were significantly higher than those of FM fermented by ST 1303 or ST 1275 without PEPS. The proteolytic activities of ST 1303 of FM with added PEPS were higher than those of FM fermented by ST 1303 without PEPS. The FM with added 0.125% PEPS had similar angiotensin-I-converting enzyme-inhibitory activity to that fermented by ST 1303 without PEPS; both were higher than those of other samples during refrigerated storage. Firmness and gumminess values of FM with added PEPS were higher than those of FM fermented by ST 1303 or ST 1275 without PEPS.

  16. Membrane fractionation of milk: state of the art and challenges

    NARCIS (Netherlands)

    Brans, G.B.P.W.; Schroën, C.G.P.H.; Sman, van der R.G.M.; Boom, R.M.

    2004-01-01

    Separation of milk into well-defined fractions will lead to a more optimal use of milk components (milk fat, casein, serum proteins) and their functional properties. In principle, membrane separation technology is well capable of large-scale fractionation of milk. Membrane processes for the isolatio

  17. Producing imitation camembert cheese using rennet casein%利用酶凝干酪素制造模拟培尔干酪

    Institute of Scientific and Technical Information of China (English)

    金太花; 金泽林

    2013-01-01

    In order to explore the possibilities of production of imitation camembert cheese, rennet casein as the source of proteins,inoculated mold starter,produced imitation camembert cheese through ripening was studied. And the cheese was carried out the analysis of sensory quality and physico-chemical properties during the period of ripening.The result indicated that there were no significant differences in evaluation scores of appearance, texture and flavor as well as the total scores between imitation camembert cheese and commercial camembert cheese(p>0.05).During the period of ripening,NPN of imitation camembert cheese was significantly increased with increasing time of ripening(p<0.01),but it's hardness and shearing force were significantly decreased with increasing the time(p <0.01).The result of electron microscope observation indicated that the structure changed from the relatively dense structure of the initial stage to the relatively macroporous net structure of medium stage. Finally,the structure became more slim,and its holes became larger,more sparse and inhomogenous.and formed fat groove shape.The research indicated that rennet casein could give us imitation camembert cheese production which was similar to traditional camembert cheese in sensory quality.%为探讨生产模拟卡门培尔干酪的可行性,以酶凝干酪素为蛋白质原料制造模拟干酪,接种霉菌发酵剂,经成熟而制得模拟卡门培尔干酪,并分析其感官品质及成熟期间的理化特性.结果表明,模拟卡门培尔干酪的外观、质地、风味评定分数及感官评定分数,均与商品卡门培尔干酪无显著差异(p>0.05):成熟期间,随模拟卡门培尔干酪成熟时间的增加,非蛋白氮含量显著增加(p <0.01),硬度与剪切力显著降低(p<0.01);电镜观察显示,干酪的结构由最初的较为致密,在中期转变为空隙相对较大的纤维网状立体结构,并于后期变纤细,空穴变大、变稀疏、

  18. Partial purification of new milk-clotting enzyme produced by Nocardiopsis sp.

    Science.gov (United States)

    Cavalcanti, M T H; Teixeira, M F S; Lima Filho, J L; Porto, A L F

    2004-05-01

    Numerous attempts have been made to replace calf rennet with other milk clotting proteases because of limited supply and increasingly high prices. The aim of this work was to investigate the characteristic of the milk-clotting enzyme from Nocardiopsis sp. The partial purification extract was obtained by fractional precipitation with ammonium sulphate. Of the fractions obtained by precipitation, 40-60% possessed the milk-clotting activity (156.25 U/mg). The chromatography of 40-100% ammonium sulphate fraction in DEAE-cellulose yielded four fractions (F4, F5, F6, F7) with milk-clotting activity. The F5 yielded the best milk-clotting activity (20 U/ml). Both crude and partially purified extract were active at the range pH 4.5-11.0, however, optimum activity was displayed at pH 11.0 and pH 7.5, respectively. The milk-clotting activity was highest at 55 degrees C for both crude and partially purified extract. The crude and partial purification extract were inactivated at 65 and 75 degrees C after 30 min.

  19. Cooperative action of bioactive components in milk fat with PPARs may explain its anti-diabetogenic properties.

    Science.gov (United States)

    Parodi, Peter W

    2016-04-01

    Type 2 diabetes and its comorbidity insulin resistance is a major public health problem in developed countries and those with the disorder have up to a fourfold increased risk of cardiovascular disease relative to those without the disease. The cardiovascular complications are believed to be due largely to multiple mechanisms relating to hyperglycemia that defines the disease. Overweight and obesity are the predominant risk factors and lifestyle changes aimed at reducing weight and increasing physical activity are the basis for prevention and treatment of type 2 diabetes. The role of diet in type 2 diabetes has been investigated widely, but the results have been inconclusive. Recently two large meta-analyses of prospective cohort studies found that dairy product consumption was inversely associated with the risk of type 2 diabetes. Numerous observational studies including large prospective studies found that a high intake of dairy fat or markers of dairy fat were inversely associated with the risk of type 2 diabetes. These observations suggest that dairy fat could contain components with anti-diabetogenic properties. Candidates for the antidiabetic affect are rumenic and vaccenic acids, phytanic and pristanic acids vitamin A and β-carotene and butyric acid. The role of these compounds in glucose homeostasis and energy balance is discussed. A common feature is that all are agonists for one or more of the three PPAR isoforms that are expressed in metabolically active tissue, such as the liver, skeletal muscle and adipose tissue where they play a critical role in regulating energy balance and the metabolism of fatty acids and glucose, the main energy sources. Because PPARs have a larger ligand binding pocket than other nuclear receptors they can be activated by a wide range of agonists. Whereas individual components may not be present in sufficient concentration to produce a physiological effect such an effect may be obtained by several components acting in concert

  20. Development of navy bean-soybean milk substitute beverages and evaluation of its nutritional and physical properties

    Science.gov (United States)

    As health-conscious consumers are increasingly looking for plant-based milk substitute beverages for weight management, cancer prevention, and overall cardiovascular health, we are exploring pulse based healthful beverages with soybean-navy bean blends of 100:0, 80:20, 60:40, 20:80, and 0:100 ratios...

  1. Correlation between somatic cell count and chemical composition of cooled raw milk in properties of Rio Grande do Norte, Brazil

    Directory of Open Access Journals (Sweden)

    Adriano Henrique do Nascimento Rangel

    2014-06-01

    Full Text Available Due to the damage caused by subclinical mastitis in loss of production and quality of milk, the present study aimed to verify the correlation between somatic cell count (SCC and the chemical composition of cooled raw milk collected in the Agreste region of Rio Grande do Norte, Brazil, in drought and rain seasons. Samples were collected in seven dairy farms during morning time, between January 2010 and March 2012, and sent to the Brazilian et of Milk Quality Laboratory (ESALQ/USP. The contents of protein, fat, lactose, casein, total solids, nonfat dry extract and urea nitrogen, besides of SCC and total bacterial count were performed. Data were submitted to analysis of variance, correlation analysis and comparison of means by Tuckey test , 5%. The average SCC was 604,000 cells/mL and had significant variation in the dry period (558 000 cells/mL and rainy (650 000 cells/mL. The SCC was positively correlated with fat and total solids but negatively with the lactose cow’s milk of bulk tank, regardless of the season in the Agreste of Rio Grande do Norte.

  2. Influence of variable water-soluble soy extract and inulin contents on the rheological, technological and sensory properties of grapeflavored yogurt-like beverages made from caprine milk

    Directory of Open Access Journals (Sweden)

    José Evangelista Santos Ribeiro

    2016-04-01

    Full Text Available The present study aimed to evaluate the influences of the partial substitution of caprine milk for water-soluble soy extract (WSSE and the addition of inulin on the rheological, technological and sensory properties of grapeflavored yogurt-like beverages. For this purpose, a Central Composite Design (CCD in conjunction with Response Surface Methodology (RSM was employed. WSSE and inulin influenced the overall acceptability of the product, whereas syneresis, water holding capacity and rheological properties (the consistency index and the flow behavior index were influenced only by the WSSE content. RSM was shown to be an adequate statistical tool that can be used for the development of formulations with specified properties in the range of the ingredient concentrations studied.

  3. Effects of gelation temperature on Mozzarella-type curd made from buffalo and cows' milk: 2. Curd yield, overall quality and casein fractions.

    Science.gov (United States)

    Hussain, Imtiaz; Yan, Jen; Grandison, Alistair S; Bell, Alan E

    2012-12-01

    The overall quality of Mozzarella-type curds made from buffalo and cows' milks were measured at gelation temperatures of 28, 34 and 39°C, and cutting times of 45, 60, 75 and 90min after chymosin addition. The curd yield and moisture content decreased with increasing gelation temperature, while whey fat losses increased. The effect of higher gelation temperature (39°C) was more pronounced in cows' milk than buffalo milk. This results in more fat losses and lower yields in both milk samples at a gelation temperature of 39°C. The minimum losses of fat and protein in rennet whey occurred at a gelation temperature of 34°C in both milk samples. The curd yield was higher in buffalo milk as compared to cows' milk. This is due to difference in total solids (fat and protein contents) of the two types of bovine milk. The different cutting times had a small effect on the yield and overall quality of curds made from both milk types. Curd moisture and loss tangent have a strong relationship with respect to effects of gelation temperature. Two different curd drainage methods (centrifugation and Buchner funnel filtration) were used to compare the final overall quality of Mozzarella-type curds made from both milk types. The α(s1) and β casein fractions were found to be in different proportions in the two milk types. The total- and casein bound-calcium were higher in buffalo milk than cows' milk. The total protein, casein and fat were also found to be higher in buffalo milk than cows' milk. Copyright © 2012 Elsevier Ltd. All rights reserved.

  4. Milk Allergy

    Science.gov (United States)

    ... lactoferrin, lactulose non-dairy creamers whey, whey hydrolysate Vegan foods are made without animal products, such as eggs or milk. You can buy vegan products at health food stores. Be careful to ...

  5. Milk fat triacylglycerols and their relations with milk fatty acid composition, DGAT1 K232A polymorphism, and milk production traits

    NARCIS (Netherlands)

    Tzompa-Sosa, D.A.; Valenberg, van H.J.F.; Aken, van G.A.; Bovenhuis, H.

    2016-01-01

    Milk fat (MF) triacylglycerols (TAG) determine the physical and functional properties of butter and products rich in MF. To predict these properties, it is necessary to understand the variability of fatty acids, TAG, their associations, and their effect on milk productive traits, days in milk (DI

  6. Propriedades fisiológicas-funcionais das proteínas do soro de leite Physiological-functional properties of milk whey proteins

    Directory of Open Access Journals (Sweden)

    Valdemiro Carlos Sgarbieri

    2004-12-01

    Full Text Available O presente artigo coloca em destaque as propriedades multifuncionais das proteínas presentes no soro de leite bovino, a começar pelo colostro que contém essas proteínas em concentrações muito elevadas e que tem por função garantir a proteção e a imunidade dos recém-nascidos. Essas mesmas proteínas continuam no leite, porém em concentrações bastante reduzidas. A utilização dessas proteínas nas formas de concentrados e isolados protéicos evidenciam propriedades muito favoráveis à saúde no sentido de diminuir o risco de doenças infecciosas e também as consideradas crônicas e/ou degenerativas. Enfatizou-se as propriedades das proteínas do soro de leite e de peptídios delas resultantes no estímulo ao sistema imunológico, na proteção contra microrganismos patogênicos e contra alguns tipos de vírus como o HIV e o vírus da hepatite C, na proteção contra vários tipos de câncer, particularmente de cólon, na proteção da mucosa gástrica contra agressão por agentes ulcerogênicos, evidenciou-se várias linhas de ação protetora das proteínas de soro contra agentes condicionadores de problemas cardiovasculares. Com base em várias propriedades funcionais das proteínas do soro de leite, discutiu-se a vantagem e os benefícios de seu uso como suplemento alimentar para atletas e esportistas em geral. Os possíveis benefícios de vários fatores de crescimento celular, presentes no soro de leite também foram discutidos.This article emphasizes the multifunctional properties of the bovine milk whey proteins, starting with the colostrum where these proteins occur in high concentrations and are reputed as responsible for the protection and passive immunization of the newborn babies. The same proteins found in colostrum in high concentrations are found in milk although at much lower concentrations. The utilization of the milk whey proteins in the form of concentrates or isolates has been found to be highly beneficial to

  7. Characterization and Selection of Lactobacilli with Probiotic Properties from Cow’s Raw Milk of “Bororo” Cattle Breeders in Dschang (Cameroon

    Directory of Open Access Journals (Sweden)

    Zambou Ngoufack François

    2012-03-01

    Full Text Available This study aimed at isolating potential probiotic lactobacilli strains from cow’s raw milk collected near the small cattle breeders in Dschang (Cameroon and applying established in vitro tests to screen those strains that could be used as novel probiotic strains in the food industry. Thirty four lactobacilli isolates obtained from raw cow’s milk were characterized and selected according to their preliminary probiotic properties including tolerance to acid and bile salts, ability to assimilate cholesterol, sensitivity to antibiotics and antimicrobial activities. Among the several requirements, the acid tolerance as well as the bile salt tolerance was strain dependent. Nine isolates exhibited the highest surviving percentage at pH 3 and 2. Six acid tolerant isolates presented an excellent tolerance at 0.2 and 0.4 % bile salts. The acid tolerant and bile tolerant isolates were sensitive to most of the antibiotics tested. Six acid and bile tolerant isolates (6M, 11M, 12M, 21M, 48M exhibited antimicrobial activity against Staphylococcus aureus, Salmonella typhi, Pseudomonas aeruginosa, Escherichia coli. These isolates reduced between 20.35 and 45.21 mg of cholesterol per g (dry weight of cells in vitro. They were identified using API 50CH kits and repetitive genomic element-PCR (Rep-PCR fingerprinting as Lactobacillus plantarum. According to the obtained results, these Lactobacillus plantarum strains (6M 11M, 12M, 21M and 48M were found to be the most promising strains with preliminary probiotic properties.

  8. Effects of gelation temperature on Mozzarella-type curd made from buffalo and cows' milk. 1: rheology and microstructure.

    Science.gov (United States)

    Hussain, Imtiaz; Grandison, Alistair S; Bell, Alan E

    2012-10-01

    The rheology and microstructure of Mozzarella-type curds made from buffalo and cows' milk were measured at gelation temperatures of 28, 34 and 39 °C after chymosin addition. The maximum curd strength (G') was obtained at a gelation temperature of 34 °C in both types of bovine milk. The viscoelasticity (tan δ) of both curds was increased with increasing gelation temperature. The rennet coagulation time was reduced with increase of gelation temperature in both types of milk. Frequency sweep data (0.1-10 Hz was recorded 90 min after chymosin addition, and both milk samples showed characteristics of weak viscoelastic gel systems. When both milk samples were subjected to shear stress to break the curd system at constant shear rate, 95 min after chymosin addition, the maximum yield stress was obtained at the gelation temperatures of 34 °C and 28 °C in buffalo and cows' curd respectively. The cryo-SEM and CLSM techniques were used to observe the microstructure of Mozzarella-type curd. The porosity was measured using image J software. The cryo-SEM and CLSM micrographs showed that minimum porosity was observed at the gelation temperature of 34 °C in both types of milk. Buffalo curd showed minimum porosity at similar gelation temperature when compared to cows' curd. This may be due to higher protein concentration in buffalo milk. Copyright © 2012 Elsevier Ltd. All rights reserved.

  9. Evaluation of the catalytic specificity, biochemical properties, and milk clotting abilities of an aspartic peptidase from Rhizomucor miehei.

    Science.gov (United States)

    da Silva, Ronivaldo Rodrigues; Souto, Tatiane Beltramini; de Oliveira, Tássio Brito; de Oliveira, Lilian Caroline Gonçalves; Karcher, Daniel; Juliano, Maria Aparecida; Juliano, Luiz; de Oliveira, Arthur H C; Rodrigues, André; Rosa, Jose C; Cabral, Hamilton

    2016-08-01

    In this study, we detail the specificity of an aspartic peptidase from Rhizomucor miehei and evaluate the effects of this peptidase on clotting milk using the peptide sequence of k-casein (Abz-LSFMAIQ-EDDnp) and milk powder. Molecular mass of the peptidase was estimated at 37 kDa, and optimum activity was achieved at pH 5.5 and 55 °C. The peptidase was stable at pH values ranging from 3 to 5 and temperatures of up 45 °C for 60 min. Dramatic reductions in proteolytic activity were observed with exposure to sodium dodecyl sulfate, and aluminum and copper (II) chloride. Peptidase was inhibited by pepstatin A, and mass spectrometry analysis identified four peptide fragments (TWSISYGDGSSASGILAK, ASNGGGGEYIFGGYDSTK, GSLTTVPIDNSR, and GWWGITVDRA), similar to rhizopuspepsin. The analysis of catalytic specificity showed that the coagulant activity of the peptidase was higher than the proteolytic activity and that there was a preference for aromatic, basic, and nonpolar amino acids, particularly methionine, with specific cleavage of the peptide bond between phenylalanine and methionine. Thus, this peptidase may function as an important alternative enzyme in milk clotting during the preparation of cheese.

  10. Tratamiento Térmico de Leche: Influencia del pH y CaCl2 en la Elaboración de Queso Cuartirolo Thermally Treated Milk: Influence of pH and CaCl2 on Cuartirolo Cheese-Making

    Directory of Open Access Journals (Sweden)

    Oscar A Sbodio

    2010-01-01

    Full Text Available Con el objeto de mejorar la propiedad de coagular de leche entera tratada bajo condiciones moderadas de temperatura, 10 minutos a 73 °C, se estudió el efecto del pH (6.2-6.6 y la adición de CaCl2 (200 y 600 mg L-1. El proceso de la coagulación enzimática, con la acidificación de Glucono-5-Lactona, fue medido con el método del alambre caliente. A pH 6.4 y 6.6 los coágulos obtenidos a partir de leche entera tratada, mostraron tiempos de coagulación significativamente inferiores (PThe effect of pH (6.2-6.6 and CaCl2 addition (200 - 600 mg L-1 was studied, with the objective of improving the coagulation properties of whole milk treated under mild condition of temperature, 10 min at 73 °C. The hot wire method to monitor rennet coagulation induced through acidification with Glucono-5-Lactone was employed. At pH 6.4 and 6.6 the coagulum of heated milk presented lower coagulation time (P<0.05, increased máximum voltage and time where they reach máximum voltage, and a decreased in whey separation, compared to those of coagulum produced by unheated milk. The selected conditions of pH 6.4 and CaCl2 added 400 mg L-1, used in the process of cuartirolo cheese proved to be the best condition to increase the yield in 8.9% on a dry basis, without loosing consumer's acceptance.

  11. Milk digesta and milk protein fractions influence the adherence of Lactobacillus gasseri R and Lactobacillus casei FMP to human cultured cells.

    Science.gov (United States)

    Volstatova, Tereza; Havlik, Jaroslav; Potuckova, Miroslava; Geigerova, Martina

    2016-08-10

    Adhesion to the intestinal epithelium is considered an important feature of probiotic bacteria, which may increase their persistence in the intestine, allowing them to exert their beneficial health effect or promote the colonisation process. However, this feature might be largely dependent on the host specificity or diet. In the present study, we investigated the effect of selected milks and milk protein fractions on the ability of selected lactobacilli to adhere to the cells of an intestinal model based on co-culture Caco-2/HT29-MTX cell lines. Most milk digesta did not significantly affect bacterial adhesion except for UHT-treated milk and sheep milk. The presence of UHT-treated milk digesta reduced the adhesion of Lactobacillus gasseri R by 61% but not that of Lactobacillus casei FMP. However, sheep milk significantly increased the adherence of L. casei FMP (P < 0.05) but not of L. gasseri R. Among the protein fractions, rennet casein (RCN) and bovine serum albumin (BSA) showed reproducible patterns and strain-specific effects on bacterial adherence. While RCN reduced the adherence of L. gasseri R to <50% compared to the control, it did not have a significant effect on L. casei FMP. In contrast, BSA reduced L. casei FMP adherence to a higher extent than that of L. gasseri R. Whey protein (WH) tended to increase the adherence of both strains by 130%-180%. Recently, interactions between the host diet and its microbiota have attracted considerable interest. Our results may explain one of the aspects of the role of milk in the development of microbiota or support of probiotic supplements. Based on our data, we conclude that the persistence of probiotic strains supplemented as part of dairy food or constitutional microbiota in the gut might be affected negatively or positively by the food matrix through complex strain or concentration dependent effects.

  12. Newly identified mutations at the CSN1S1 gene in Ethiopian goats affect casein content and coagulation properties of their milk.

    Science.gov (United States)

    Mestawet, T A; Girma, A; Adnøy, T; Devold, T G; Vegarud, G E

    2013-08-01

    Very high casein content and good coagulation properties previously observed in some Ethiopian goat breeds led to investigating the αs1-casein (CSN1S1) gene in these breeds. Selected regions of the CSN1S1 gene were sequenced in 115 goats from 5 breeds (2 indigenous: Arsi-Bale and Somali, 1 exotic: Boer, and 2 crossbreeds: Boer × Arsi-Bale and Boer × Somali). The DNA analysis resulted in 35 new mutations: 3 in exons, 3 in the 5' untranslated region (UTR), and 29 in the introns. The mutations in exons that resulted in an amino acid shift were then picked to evaluate their influence on individual casein content (αs1-, αs2-, β-, and κ-CN), micellar size, and coagulation properties in the milk from the 5 goat breeds. A mutation at nucleotide 10657 (exon 10) involved a transversion: CAG→CCG, resulting in an amino acid exchange Gln77→Pro77. This mutation was associated with the indigenous breeds only. Two new mutations, at nucleotide 6072 (exon 4) and 12165 (exon 12), revealed synonymous transitions: GTC→GTT in Val15 and AGA→AGG in Arg100 of the mature protein. Transitions G→A and C→T at nucleotides 1374 and 1866, respectively, occurred in the 5' UTR, whereas the third mutation involved a transversion T→G at nucleotide location 1592. The goats were grouped into homozygote new (CC), homozygote reference (AA), and heterozygote (CA) based on the nucleotide that involved the transversion. The content of αs1-CN (15.32g/kg) in milk samples of goats homozygous (CC) for this newly identified mutation, Gln77→Pro77 was significantly higher than in milks of heterozygous (CA; 9.05g/kg) and reference (AA; 7.61g/kg) genotype animals. The αs2-, β-, and κ-CN contents showed a similar pattern. Milk from goats with a homozygous new mutation had significantly lower micellar size. Milk from both homozygote and heterozygote new-mutation goats had significantly shorter coagulation rate and stronger gel than the reference genotype. Except the transversion, the

  13. Mediterranean milk and milk products.

    Science.gov (United States)

    Hinrichs, Jörg

    2004-03-01

    Milk and dairy products are part of a healthy Mediterranean diet which, besides cow's milk, also consists of sheep's, goat's and buffalo's milk--alone or as a mixture---as raw material. The fat and protein composition of the milk of the various animal species differs only slightly, but in every case it has a high priority in human nutrition. The milk proteins are characterized by a high content of essential amino acids. Beyond that macromolecules,which have various biological functions, are available or may be formed by proteolysis in milk. Taking this into consideration, the technology of different well-known Italian and German cheese types is presented and the differences as well as correspondences regarding nutrition are discussed. Especially Ricotta and Mascarpone are discussed in detail. Ricotta represents a special feature as this cheese is traditionally made of whey and cream. Thus the highly valuable whey proteins which contain a higher amount of the amino acids lysine, methionine and cysteic acid in comparison to casein and, additionally, to soy protein, are made usable for human nutrition. Finally, it is pointed out on the basis of individual examples that technologies to enrich whey proteins in cheese are already available and in use. Thus, the flavor of low fat cheese is improved and the nutritional value is increased.

  14. Evaluation of lipolysis and volatile compounds produced by three Penicillium roqueforti commercial cultures in a blue-type cheese made from ovine milk

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    E. Salvatore

    2015-12-01

    Full Text Available The aim of this work was to compare the effect of three different Penicillium roqueforti commercial cultures (named PS1, PS2 and PS3 on proteolysis, lipolysis and volatile flavour profile of a blue cheese made from ovine milk and lamb paste rennet. Proteolytic parameters were not significantly affected by the Penicillium roqueforti culture, while cheeses manufactured using PS2 and PS3 cultures showed the higher amount of free fatty acids (FFA and volatile FFA when compared with PS1 culture after 30 days of ripening. This study can provide important information for obtainingthe desired extent of lipolysis in this type of blue cheese.

  15. Milk production characteristics in Southern Brazil

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    Tony Picoli

    2015-07-01

    Full Text Available This paper aimed to describe milk production in Southern Rio Grande do Sul state, Brazil, and to identify factors that affect milk quality at this region. The average age of regional dairy farmers is 49, and 67.9% has not concluded elementary school. Dairy farming is carried out on properties with an average of 26.06 hectares and 8.4 lactating cows. Most of them (32.83% yield 50 to 100 L/day. Among the properties, 13.21% yield up to 30 L/day, and only 1.89% produces over 500 milk liters a day. Average yield was 6.8 L/day. Regarding to milking procedure, 39.3% farmers milk manually the animals, only 14.2% performed pre-milking teat disinfection, and 53.9% uses a single cloth to dry all animal teats. For infrastructure, 52.8% milks animals in wooden cowsheds. We observed that the average somatic cell count (SCC was within legal parameters, presenting negative correlation with milk production (r = -0.23 and lactose content (r = -0.39. However, the total bacterial count (TBC was above legal parameters. Education level seems to interfere in management and milk quality, because the less educated groups are, the less adequate are infrastructure, management, and product quality. Data show that there is a lower quality milk production where poor management techniques are adopted and owner education level affects milk quality.

  16. The effect of non-standard heat treatment of sheep's milk on physico-chemical properties, sensory characteristics, and the bacterial viability of classical and probiotic yogurt.

    Science.gov (United States)

    Zamberlin, Šimun; Samaržija, Dubravka

    2017-06-15

    Classical and probiotic set yogurt were made using non-standard heat treatment of sheep's milk at 60°C/5min. Physico-chemical properties, sensory characteristics, and the viability of bacteria that originated from cultures in classical and probiotic yogurt were analysed during 21days of storage at 4°C. For the production of yogurt, a standard yogurt culture and a probiotic strain Lactobacillus rhamnosus GG were used. At the end of storage time of the classical and probiotic yogurt the totals of non-denatured whey proteins were 92.31 and 91.03%. The viability of yogurt culture bacteria and Lactobacillus rhamnosus GG were higher than 10(6)cfu/g. The total sensory score (maximum - 20) was 18.49 for the classical and 18.53 for the probiotic. In nutritional and functional terms it is possible to produce classical and probiotic sheep's milk yogurt by using a non-standard temperature of heat treatment with a shelf life of 21days.

  17. Influence of different emulsifiers on characteristics of eggless cake containing soy milk: Modeling of physical and sensory properties by mixture experimental design.

    Science.gov (United States)

    Rahmati, Nazanin Fatemeh; Mazaheri Tehrani, Mostafa

    2014-09-01

    Emulsifiers of different structures and functionalities are important ingredients usually used in baking cakes with satisfactory properties. In this study, three emulsifiers including distilled glycerol mono stearate (DGMS), lecithin and sorbitan mono stearate (SMS) were used to bake seven eggless cakes containing soy milk and optimization was performed by using mixture experimental design to produce an eggless cake sample with optimized properties. Physical properties of cake batters (viscosity, specific gravity and stability), cake quality parameters (moisture loss, density, specific volume, volume index, contour, symmetry, color and texture) and sensory attributes of eggless cakes were analyzed to investigate functional potential of the emulsifiers and results were compared with those of control cake containing egg. Almost in all cases emulsifiers, compared to the control cake, changed properties of eggless cakes significantly. Regarding models of different response variables (except for some properties) and their high R(2) (99.51-100), it could be concluded that models obtained by mixture design were significantly fitted for the studied responses.

  18. 全脂乳粉和脱脂乳粉在1kHz~10MHz下的介电特征研究%Dielectric properties of whole milk powder and skimmed milk powder from 1kHz to 10MHz

    Institute of Scientific and Technical Information of China (English)

    金亚美; 王宁; 孟彤; 崔文华; 郭光辉; 杨哪; 金征宇; 徐学明

    2012-01-01

    The dielectric constant and loss factor of powder of four whole milk and skimmed milk over the frequency range from lkHz to 10MHz were measured at room temperature.The results indicated that the dielectric constant, loss factor and depth of penetration of powder of whole milk and skimmed milk decreased monotonically as frequency increased,and there were no obvious difference between the cultivars of powder on whole milk and skimmed milk.The dielectric constant and loss factor of whole milk powder were higher than those of skimmed milk.The whole milk powder exhibited significant drop in loss factor and inverse proportion linear relationships were evident between the log of frequency and loss factor below 10^5Hz, but this was not found in the skimmed milk powder.The contents of fat and lactose were related with dielectric properties.%分别研究了各4种不同品种的全脂乳粉和脱脂乳粉在1kHz~10MHz波段的介电特性。结果发现:随着频率的增加,全脂乳粉和脱脂乳粉的ξ'和ξ″值呈单调递减趋势;全脂乳粉的ξ'和ξ″值都高于脱脂乳粉,相同类型乳粉各品种间的ξ'和ξ″差异不大;全脂乳粉的ξ″值在103~105Hz频率段减小趋势明显,且ξ″值的对数与频率的对数成线性反比关系,而脱脂乳粉无此规律;全脂乳粉和脱脂乳粉的穿透深度Dp随频率的提高而减小,两类乳粉的介电特性差异可能与它们各自的脂肪和乳糖含量有关。

  19. PENGARUH DEKSTRIN DAN GUM ARAB TERHADAP SIFAT KIMIA DAN FISIK BUBUK SARI JAGUNG MANIS (Zeamays saccharata [The Effects of Dextrin and Arabic Gum on Chemical and Physical Properties of Sweet Corn (Zeamays saccharata Milk-like Powder

    Directory of Open Access Journals (Sweden)

    Sutardi*

    2010-12-01

    Full Text Available The aim of this research was to determine the effects of type and amount of binder on the chemical and physical properties of sweet corn milk-like powder. Sweet corn milk-like powder was prepared from sweet corn kernel extracted with water with ratio of water and kernel of 2:1 (v/w, then dehydrated by spray dryer. Dextrin and arabic gum in various amount i.e. 2.5; 5.0; and 7.5% (w/v, respectively were added to the sweet corn milk-like before drying, and control was also made. The reducing sugar and total sugar, protein, fat, and moisture content, and as well as bulk density, colour, and solubility of the powder were then analyzed. The chemical and physical properties of sweet corn milk-like powder with addition of dextrin and arabic gum in the amount of 2.5; 5.0; and 7.5% (w/v were significantly different (p > 0.05. According to all aspects studied, sweet corn milk-like powder with addition of dextrin in the amount of 2.5% was the best product of all, which had reducing sugar of 5.00% (db; total sugar 17.01% (db; protein13.67% (db; fat 5.97% (db; moisture 5.38%; bulk density 0.47 g/cm3; and solubility of 93.70%.

  20. Characteristics of dietary and quality attributes of mare milk lyophilisates

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    Romualda Danków

    2013-12-01

    Full Text Available Mare milk due to its 40% share of whey proteins is defined as albumin milk. It is rich in polyunsaturated fatty acids, as well as lysozyme and lactoferrin, exhibiting antibacterial properties. Since mare milk is a seasonal product, it was attempted to lyophilise it to provide its supply throughout the year. The aim of the study was to characterise selected functional properties of lyophilised mare milk, determine the composition of fatty acids and aroma compounds in mare milk lyophilisate, as well as evaluate liquid milk as a raw material for the production of lyophilised milk. Milk for the production of lyophilisate was characterised by very high hygienic quality and low contents of fat and protein. Results of analyses indicated a slight deterioration of physico-chemical, microbiological and organoleptic characteristics of cold-stored milk lyophilisate.

  1. Effects of Homogenization and Ultra-high Temperature Processing on the Properties of Whole Milk Concentrated by a Multiple-Membrane Separation System

    OpenAIRE

    Chang, Chien-Ti

    1995-01-01

    Three different concentrated whole milks (2.5x, 2.75x, and 3.0x) were produced by mixing equal parts of ultrafiltration retentate of whole milk and reverse osmosis retentate of the UF milk permeate. The concentrated whole milks were ultra-high temperature processed by direct steam injection (140.6°C) followed by flash cooling and two-stage homogenization pressures (2500/500 psi, 3500/700 psi, or 4500/900 psi). The milk concentrates were packaged aseptically and stored at room temperature. On ...

  2. Milk Money

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    China’s leading food company has expanded its business into the dairy industry A combined financial venture between China’s largest agricultural trading and processing company and a private equity firm formed to milk profits from the dairy business has led to

  3. Storage of Human Breast Milk

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    Gamze Can

    2007-10-01

    Full Text Available Storage of human breast milk by freezing or refrigeration of milk has been recommended especially at some social circumstances of most mothers who are regularly separated from their infants because of work. The greatest fear that has hindered the prospects of in - vitro storage of breast milk for any considerable period of time is the possibility of bacterial contamination and growth of infectious pathogens in the stored milk, there by rendering them unsafe for human consumption. The storage container can influence the cell content of milk, as the cells adhere to the walls of a glass container but not to polyethylene or polypropylene containers. Bacteriological examination of refrigerated milks has proven their safety for human consumption for even up to 72 h. For a storage over longer periods up to 1 month, freezing at - 20 0C could be recommended, but the most preferred method, especially for longer storage would be fresh freezing at - 70 0C, if affordable or available. The nutrient value of human milk is essentially unchanged, but the immunological properties are reduced by various storage techniques. Boiling and microwave radiation have not been recommended. [TAF Prev Med Bull 2007; 6(5.000: 375-379

  4. An odor timer in milk? Synchrony in the odor of milk effluvium and neonatal chemosensation in the mouse.

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    Syrina Al Aïn

    Full Text Available Mammalian newborns exhibit avid responsiveness to odor compounds emanating from conspecific milk. Milk is however developmentally heterogeneous in composition as a function of both evolved constraints and offspring demand. The present study aimed to verify whether milk odor attractivity for neonates is equally distributed along lactation in Mus musculus (Balb-c strain. Therefore, we exposed pups varying in age to milk samples collected from females in different lactational stages. The pups were assayed at postnatal days 2 (P2, 6 (P6 and 15 (P15 in a series of paired-choice tests opposing either murine milk and a blank (water, or two samples of milk collected in different stages of lactation [lactation days 2 (L2, 6 (L6, and 15 L15]. Pups of any age were able to detect, and were attracted to, the odor of the different milk. When milk from different lactational stages were simultaneously presented, P2 pups oriented for a similar duration to the odors of L2 and of L6 milk, but significantly less to the odor of L15 milk. Next, P6 pups roamed equivalently over L2 and L6 milk odors, but still less over the odor of L15 milk. Finally, P15 pups explored as much L15 milk odor as the odors of both L2 and L6 milk. This developmental shift in milk attractivity is discussed in terms of changing chemosensory properties of milk and of shifting chemosensory abilities/experience of pups.

  5. An odor timer in milk? Synchrony in the odor of milk effluvium and neonatal chemosensation in the mouse.

    Science.gov (United States)

    Al Aïn, Syrina; Belin, Laurine; Patris, Bruno; Schaal, Benoist

    2012-01-01

    Mammalian newborns exhibit avid responsiveness to odor compounds emanating from conspecific milk. Milk is however developmentally heterogeneous in composition as a function of both evolved constraints and offspring demand. The present study aimed to verify whether milk odor attractivity for neonates is equally distributed along lactation in Mus musculus (Balb-c strain). Therefore, we exposed pups varying in age to milk samples collected from females in different lactational stages. The pups were assayed at postnatal days 2 (P2), 6 (P6) and 15 (P15) in a series of paired-choice tests opposing either murine milk and a blank (water), or two samples of milk collected in different stages of lactation [lactation days 2 (L2), 6 (L6), and 15 L15)]. Pups of any age were able to detect, and were attracted to, the odor of the different milk. When milk from different lactational stages were simultaneously presented, P2 pups oriented for a similar duration to the odors of L2 and of L6 milk, but significantly less to the odor of L15 milk. Next, P6 pups roamed equivalently over L2 and L6 milk odors, but still less over the odor of L15 milk. Finally, P15 pups explored as much L15 milk odor as the odors of both L2 and L6 milk. This developmental shift in milk attractivity is discussed in terms of changing chemosensory properties of milk and of shifting chemosensory abilities/experience of pups.

  6. The composition and functional properties of whey protein concentrates produced from buttermilk are comparable with those of whey protein concentrates produced from skimmed milk.

    Science.gov (United States)

    Svanborg, Sigrid; Johansen, Anne-Grethe; Abrahamsen, Roger K; Skeie, Siv B

    2015-09-01

    The demand for whey protein is increasing in the food industry. Traditionally, whey protein concentrates (WPC) and isolates are produced from cheese whey. At present, microfiltration (MF) enables the utilization of whey from skim milk (SM) through milk protein fractionation. This study demonstrates that buttermilk (BM) can be a potential source for the production of a WPC with a comparable composition and functional properties to a WPC obtained by MF of SM. Through the production of WPC powder and a casein- and phospholipid (PL)-rich fraction by the MF of BM, sweet BM may be used in a more optimal and economical way. Sweet cream BM from industrial churning was skimmed before MF with 0.2-µm ceramic membranes at 55 to 58°C. The fractionations of BM and SM were performed under the same conditions using the same process, and the whey protein fractions from BM and SM were concentrated by ultrafiltration and diafiltration. The ultrafiltration and diafiltration was performed at 50°C using pasteurized tap water and a membrane with a 20-kDa cut-off to retain as little lactose as possible in the final WPC powders. The ultrafiltrates were subsequently spray dried, and their functional properties and chemical compositions were compared. The amounts of whey protein and PL in the WPC powder from BM (BMWPC) were comparable to the amounts found in the WPC from SM (SMWPC); however, the composition of the PL classes differed. The BMWPC contained less total protein, casein, and lactose compared with SMWPC, as well as higher contents of fat and citric acid. No difference in protein solubility was observed at pH values of 4.6 and 7.0, and the overrun was the same for BMWPC and SMWPC; however, the BMWPC made less stable foam than SMWPC.

  7. Physicochemical properties and sensory acceptability of goat’s milk fruit yogurts with mango and banana using accelerated testing

    Directory of Open Access Journals (Sweden)

    Víctor Aredo

    2015-09-01

    Full Text Available Two types of skimmed (fat 3% goat’s milk fruit yogurt with mango (YM and banana (YB were stored at temperatures of 5 °C, 15 °C and 25 °C for 72 hours. Every 24 hours the pH, titratable acidity, total solids, fat and protein were analyzed. Sensory acceptability was also evaluated with 75 yogurt frequent consumers, who responded with "yes" or "no" to the question ¿would you consume this product? At the beginning pH, acidity, total solids, fat and protein were 4.35 and 4.36; 0.76% and 0.75%; 12.71% and 13.23%; 3.2% and 3.3%; 4.4% and 4.5%, for the YM and YB respectively, meeting known standards for cow's milk yogurt: range of acidity 0.5%-1.6%, fat maximum value 15% and protein minimum value 2.7%. The sensory acceptability of the YM and the YB was high, with 88.9% and 94.7%, respectively. During storage under accelerated conditions, pH decreased to 3.88 and 3.92; titrable acidity increased to 1.1% and 0.93%; total solids, fat and protein decreased to 9.37% and 9.7%; 2.4% and 2.0%; 2.5% and 2.6%, for the YM and YB respectively, while remaining within the limits of the standards consulted. The sensory acceptability decreased to 4% and 5.33% for YM and YB respectively. Therefore the shelf life of the sensory acceptability was estimated (S.S.A at 4 °C in a rejection percentage of 25% and 50%, 69 and 49 h; 193 and 111 h, for the YM and YB respectively.

  8. Optimisation of chocolate formulation using dehydrated peanut-cowpea milk to replace dairy milk.

    Science.gov (United States)

    Aidoo, Herta; Sakyi-Dawson, Esther; Abbey, Lawrence; Tano-Debrah, Kwaku; Saalia, Firibu Kwesi

    2012-01-30

    The rheological properties of chocolate, based upon its acceptability by consumers, are determined largely by the ingredients and their proportions used in the formulations. Milk chocolates are very popular because milk provides flavour and smooth texture to the product. This study aimed to determine the optimal ingredient formulation for vegetable milk chocolate using peanut-cowpea milk as a substitute for dairy milk. The study followed a four-component constrained mixture design, with cocoa liquor, vegetable milk, cocoa butter and sugar as the components. Lecithin and vanillin were added at a constant amount to all formulations. Critical attributes of the chocolates were evaluated using descriptive sensory tests and instrumental techniques. Regression models were fitted to the data, and the optimum ingredient formulation for acceptable vegetable milk chocolate was determined. The vegetable milk had significant (P = 0.05) influence on flavour, mouth feel, hardness and after taste of chocolates. The optimum ingredient formulation for acceptable vegetable milk chocolates was determined to be cocoa liquor (18.00%), sugar (30.75%), peanut-cowpea milk (28.93%), and cocoa butter (22.32%). The results demonstrate that it is feasible to use vegetable source milk for chocolate. The findings also provide clues for scale-up criteria for large-scale production of vegetable milk chocolate. Copyright © 2011 Society of Chemical Industry.

  9. Digital Prototyping of Milk Products

    DEFF Research Database (Denmark)

    Frisvad, Jeppe Revall; Nielsen, Otto Højager Attermann; Skytte, Jacob Lercke

    2012-01-01

    of most foods make them much more challenging to visualise and simulate realistically. We present models and methods that take steps toward digital prototyping of milk products and other food colloids. To simulate the dynamics of liquid products that only exist digitally, we use deformable simplicial...... or asymmetry parameter) are the input needed for a Monte Carlo based graphical rendering. We have developed a model for predicting the optical properties of milk as a function of its fat and protein contents [4]. However, the model has only been validated to a limited extent. We suggest that diffuse...... reflectance measurements can be used for more extensive validation and for gathering data that can be used to extend our current model such that it can also predict how the optical properties develop during fermentation or acidification of milk to yogurt. A well-established way of measuring optical properties...

  10. Lactobacillus gasseri requires peptides, not proteins or free amino acids, for growth in milk.

    Science.gov (United States)

    Arakawa, K; Matsunaga, K; Takihiro, S; Moritoki, A; Ryuto, S; Kawai, Y; Masuda, T; Miyamoto, T

    2015-03-01

    Lactobacillus gasseri is a widespread commensal lactic acid bacterium inhabiting human mucosal niches and has many beneficial effects as a probiotic. However, L. gasseri is difficult to grow in milk, which hurts usability for the food industry. It had been previously reported that supplementation with yeast extract or proteose peptone, including peptides, enables L. gasseri to grow well in milk. In this study, our objective was to confirm peptide requirement of L. gasseri and evaluate efficacy of peptide release by enzymatic proteolysis on growth of L. gassei in milk. Three strains of L. gasseri did not grow well in modified DeMan, Rogosa, Sharpe broth without any nitrogen sources (MRS-N), but addition of a casein-derived peptide mixture, tryptone, promoted growth. In contrast, little effect was observed after adding casein or a casein-derived amino acid mixture, casamino acids. These results indicate that L. gasseri requires peptides, not proteins or free amino acids, among milk-derived nitrogen sources for growth. Lactobacillus gasseri JCM 1131T hardly had growth capacity in 6 kinds of milk-based media: bovine milk, human milk, skim milk, cheese whey, modified MRS-N (MRSL-N) supplemented with acid whey, and MRSL-N supplemented with casein. Moreover, treatment with digestive proteases, particularly pepsin, to release peptides made it grow well in each milk-based medium. The pepsin treatment was the most effective for growth of strain JCM 1131T in skim milk among the tested food-grade proteases such as trypsin, α-chymotrypsin, calf rennet, ficin, bromelain, and papain. As well as strain JCM 1131T, pepsinolysis of milk improved growth of other L. gasseri strains and some strains of enteric lactobacilli such as Lactobacillus crispatus, Lactobacillus gallinarum, Lactobacillus johnsonii, and Lactobacillus reuteri. These results suggest that some relatives of L. gasseri also use peptides as desirable nitrogen sources, and that milk may be a good supplier of nutritious

  11. Effect of diets with different content of starch and protein fed to dairy cows in early lactation on milk yield and traits

    Directory of Open Access Journals (Sweden)

    Paolo Bani

    2010-01-01

    Full Text Available With the aim to study the effect on milk yield and its traits of 2 different levels of fermentable carbohydrates (LS: 25.5%, and HS: 29.5% DM combined with 2 protein levels (LP: 15.5% and HP: 16.5% DM, 4 Italian Friesian dairy cows in early lactation housed in a tied stall were used. The experimental diets were obtained adjusting in 4 supplements the proportion of high energy fibrous (beet pulp, soybean hull or starchy (corn meal feeds and of meal protein more (soybean meal or less (Soy-Pass®: xylose-treated soybean meal degradable. The highest DMI was observed in HSHP which showed also a low content of NDF. Milk yield resulted over 45 kg/d throughout the study and higher when HSHP diet was fed (46.1 kg. Milk fat was always at high level and the lowest value (3.89% with HSHP and the highest (4.08% with LSLP were observed. The diets did not modified milk protein (their average levels resulted of 3.25% and lactose content. Milk acidity and renneting traits were higher when HSLP was fed, and resulted at adequate levels when all the diets were fed. When the diets for dairy cow are formulated to cover the animal requirements and respect their digestion physiology, it is possible to reach high milk yield level and maintaining, at the same time, a high milk quality .

  12. Exploring human breast milk composition by NMR-based metabolomics.

    Science.gov (United States)

    Praticò, Giulia; Capuani, Giorgio; Tomassini, Alberta; Baldassarre, Maria Elisabetta; Delfini, Maurizio; Miccheli, Alfredo

    2014-01-01

    Breast milk is a complex fluid evolutionarily adapted to satisfy the nutritional requirements of growing infants. In addition, milk biochemical and immunological components protect newborns against infective agents in the new environment. Human milk oligosaccharides, the third most abundant component of breast milk, are believed to modulate the microbiota composition, thus influencing a wide range of physiological processes of the infant. Human milk also contains a number of other bioactive compounds, the functional role of which has not yet been clearly elucidated. In this scenario, NMR-based metabolic profiling can provide a rapid characterisation of breast milk composition, thus allowing a better understanding of its nutritional properties.

  13. Simulation and Flexibility Analysis of Milk Production Process

    DEFF Research Database (Denmark)

    Cheng, Hongyuan; Friis, Alan

    In this work, process simulation method is used to simulate pasteurised market milk production line. A commercial process simulation tool - Pro/II from Simulation Science Inc. is used in the simulation work. In the simulation, a new model is used to calculate the thermal property of milk....... In this work, a simulator is obtained for the milk production line. Using the simulator, different milk processing situation can be quantitatively simulated investigated, such as different products production, capacity changes, fat content changes in raw milk, energy cost at different operation conditions etc....... As the pasteurised market milk production line involves typical milk processing steps, such as pasteurisation, centrifugal separation, standardisation, the simulator can be modified to simulate similar milk processing lines. In many cases, the rapidly changed market requires a flexible milk production line...

  14. Milk metabolites as indicators of mammary gland functions and milk quality.

    Science.gov (United States)

    Silanikove, Nissim; Merin, Uzi; Shapiro, Fira; Leitner, Gabriel

    2014-08-01

    The assumption, that metabolites derived from the activity of the mammary gland epithelial cells reflect changes in milk secretion and its coagulation properties, was tested in dairy cows. The experiment included cows with uninfected udders and cows with one of the glands infected by different bacteria specie. Analysis were carried at the cow level (including all four glands), or at the gland level. High and significant correlations among the concentrations of lactose, glucose, glucose-6-posphate, milk related respiratory index (the ratio between the concentrations of citrate/lactate+malate in milk) and milk-derived glycolytic index (the ratio between glucose-6-phosphate and glucose in milk) and milk clotting parameters were found. The physiological basis for these relations and their ability to predict the deterioration in milk quality in subclinically infected glands and in glands previously clinically infected with Escherichia coli are discussed.

  15. Excretion of drugs in human breast milk

    Energy Technology Data Exchange (ETDEWEB)

    Welch, R.M.; Findlay, J.W.

    1981-01-01

    The present report briefly discusses some of the morphological, physiological, and compositional aspects of animal and human breast milk and how these characteristics might be important for the accumulation of drugs and foreign compounds. In addition, a study is described confirming the presence of caffeine, codeine, morphine, phenacetin, acetaminophen, and salicylic acid in the breast milk of a lactating mother following oral administration of a combination analgesic containing aspirin, phenacetin, caffeine, and codeine. Although the study is limited to one subject, it has provided critically needed data on the rates of appearance in, and elimination of these drugs from, breast milk. A similar amount of information is presented on phenacetin, also a component of the analgesic mixture, which has not been previously reported to enter human milk. The distribution of these drugs between the slightly more acidic breast milk and the relatively neutral plasma is consistent with their weakly basic, acidic, or relatively neutral properties. In general, the study shows that codeine and morphine milk concentrations are higher than, salicylic acid milk levels are much lower than, and phenacetin, caffeine, and acetaminophen milk concentrations are relatively similar to their respective plasma levels. It is projected, from estimated steady-state milk concentrations of the drugs and their metabolites studied, that very low percentages of the therapeutic dosages (less than 0.7%) would be excreted in mother's milk, too low an amount to be clinically significant to the infant.

  16. Pregnancy test via milk

    NARCIS (Netherlands)

    Siemes, H.; Woelders, H.

    2011-01-01

    Determining a pregnancy through the milk. Wageningen University is researching the possibilities. The first steps have been taken. Researchers have identified five milk proteins that release a signal of a pregnancy. A pregnancy test via the milk comes within sight.

  17. Comparative studies on the chemical and cell-based antioxidant activities and antitumor cell proliferation properties of soy milk manufactured by conventional and commercial UHT methods.

    Science.gov (United States)

    Xu, Baojun; Chang, Sam K C; Liu, Zhisheng; Yuan, Shaohong; Zou, Yanping; Tan, Yingying

    2010-03-24

    The aims of this work were to compare antiproliferation, antioxidant activities and total phytochemicals and individual isoflavone profiles in soy milk processed by various methods including traditional stove cooking, direct steam injection, direct ultrahigh temperature (UHT), indirect UHT, and a two-stage simulated industry method, and a selected commercial soy milk product. Various processing methods significantly affected total saponin, phytic acid, and total phenolic content and individual isoflavone distribution. The laboratory UHT and the two-stage processed soy milk exhibited relatively higher total phenolic content, total flavonoid content, saponin and phytic acid than those processed by the traditional and steam processed methods. Thermal processing caused obvious intertransformation but did not cause severe degradation except for breaking down of aglycons. Thermal processing significantly increased antioxidant capacities of soy milk determined by chemical analyses, but decreased cellular antioxidant capacities as compared to the raw soy milk. The raw and all processed soy milk exhibited antipoliferative activities against human HL-60 leukemia cells, AGS gastric tumor cells, and DU145 prostate cancer cells in a dose-dependent manner. The raw soy milk, but not the processed soy milk, exhibited a dose-dependent antiproliferative effect against colorectal adenocarcinoma Caco-2 cells. Taken together, these results indicate that various thermal processing methods change not only phytochemcials but also potential health-promoting effects of soy milk.

  18. FERMENTED MILK AS A FUNCTIONAL FOOD

    Directory of Open Access Journals (Sweden)

    Irena Rogelj

    2000-06-01

    Full Text Available Certain foods have been associated with health benefits for many years; fermented milks and yoghurt are typical examples. The health properties of these dairy products were a part of folklore until the concept of probiotics emerged, and the study of fermented milks and yoghurt containing probiotic bacteria has become more systematic. Functional foods have thus developed as a food, or food ingredient, with positive effects on host health and/or well-being beyond their nutritional value, and fermented milk with probiotic bacteria has again become the prominent representative of this new category of food. Milk alone is much more than the sum of its nutrients. It contains an array of bioactivities: modulating digestive and gastrointestinal functions, haemodynamics, controlling probiotic microbial growth, and immunoregulation. When fermented milk is enriched with probiotic bacteria and prebiotics it meets all the requirements of functional food. The possible positive effects of enriched fermented milk on host health will be reviewed.

  19. SOUR MILK FORMULAS IN NUTRITION OF INFANTS

    Directory of Open Access Journals (Sweden)

    E.F. Lukushkina

    2010-01-01

    Full Text Available Health-giving properties of fermented food are related to the fact, that acid medium improves assimilation of protein and fat, increases absorption of iron and zinc, improves digestion. But the kefir and other sour milk food based on the whole milk can’t be used in nutrition of infants as human milk substitute because of high content of protein, high osmolarity, deficiency of vitamins and microelements. The article describes the results of clinical approbation of new modern sour milk formula «NAN sour milk», containing proper amount of high-quality protein (OptiPro, enriched with lactalbumin and all sufficient vitamins and microelements. This mixture contains also probiotics (B. lactis, providing high functionality of this food. Key words: infants, sour milk formula, nutrition.(Voprosy sovremennoi pediatrii — Current Pediatrics. 2010;9(1:136-141

  20. Milking hygiene: new issues and opportunities from automatic milking

    OpenAIRE

    Lotte Bach Larsen; Morten Dam Rasmussen

    2010-01-01

    Automatic milking offers the opportunity of in-line measurements of milk components, check of milking and cleaning procedures,and surveillance through the management program. These advantages may directly benefit the milk quality.Diversion of abnormal milk at time of milking is critical to the milk quality. It is proposed to define abnormal milk as milkbeing visibly changed in homogeneity or colour from that of normal milk. Several enzymes and other milk componentsmay be involved in the forma...

  1. Comparative Analysis of the Physicochemical Parameters of Breast Milk, Starter Infant Formulas and Commercial Cow Milks in Serbia

    Directory of Open Access Journals (Sweden)

    Sunarić Slavica

    2016-06-01

    Full Text Available Data on the physical properties of cow milk and infant formulas are important since they indicate the differences in physicochemical and rheological characteristics and compatibility with natural breast milk. This fact is important not only for quality control but also for the use of these commercial products as infant diet supplements or as complete breast milk substitutes. This study was undertaken to determine refractive index, surface tension, pH, electrical conductivity, viscosity and titratable acidity of the UHT cow milk, starter infant formulas and breast milk of Serbian mothers in order to compare commercial milk formulations with natural human milk. The paper also presents the measured data of some physical parameters of human milk about which there is little information in the literature. It has been also demonstrated how these parameters were changed by freezing and prolonged storage of breast milk.

  2. Allergenicity of milk of different animal species in relation to human milk.

    Science.gov (United States)

    Pastuszka, Robert; Barłowska, Joanna; Litwińczuk, Zygmunt

    2016-12-31

    Protein content in cow milk (with over 20 proteins, and peptides may also occur as a result of enzymatic hydrolysis) ranges from 2.5% to 4.2% and is about 1.5-2 times higher than in human milk. Its most important allergens are considered to be β-lactoglobulin (absent in human milk) and αs1-casein. The most similar in composition to human milk is horse and donkey milk. It contains considerably more whey proteins (35-50%) than cow milk (about 20%), and the concentration of the most allergenic casein fraction αs1 is 1.5-2.5 g/l. In comparison, the content of αs1-casein in cow milk is about 10 g/l. β-lactoglobulin present in donkey milk is a monomer, while in milk of ruminants it is a dimer. Like human milk, it contains a substantial amount of lactose (about 7%), which determines its flavour and facilitates calcium absorption. The high lysozyme content (about 1 g/l) gives it antibacterial properties (compared to trace amounts in ruminants). Camel milk is also more digestible and induces fewer allergic reactions, because it lacks β-lactoglobulin, and its β-casein has a different structure. It also contains (compared to cow milk) more antibacterial substances such as lysozyme, lactoferrin and immunoglobulins, and furthermore the number of immunoglobulins is compatible with human ones. Goat milk components have a higher degree of assimilability as compared to cow milk. Its main protein is β-casein, with total protein content depending on the αs1-casein genetic variant. Goats with the '0' variant do not synthesize this allergenic protein. Clinical and immunochemical studies indicate, however, that it cannot be a substitute for cow milk without the risk of an anaphylactic reaction.

  3. Allergenicity of milk of different animal species in relation to human milk

    Directory of Open Access Journals (Sweden)

    Robert Pastuszka

    2016-12-01

    Full Text Available Protein content in cow milk (with over 20 proteins, and peptides may also occur as a result of enzymatic hydrolysis ranges from 2.5% to 4.2% and is about 1.5-2 times higher than in human milk. Its most important allergens are considered to be β-lactoglobulin (absent in human milk and αs1-casein. The most similar in composition to human milk is horse and donkey milk. It contains considerably more whey proteins (35-50% than cow milk (about 20%, and the concentration of the most allergenic casein fraction αs1 is 1.5-2.5 g/l. In comparison, the content of αs1-casein in cow milk is about 10 g/l. β-lactoglobulin present in donkey milk is a monomer, while in milk of ruminants it is a dimer. Like human milk, it contains a substantial amount of lactose (about 7%, which determines its flavour and facilitates calcium absorption. The high lysozyme content (about 1 g/l gives it antibacterial properties (compared to trace amounts in ruminants. Camel milk is also more digestible and induces fewer allergic reactions, because it lacks β-lactoglobulin, and its β-casein has a different structure. It also contains (compared to cow milk more antibacterial substances such as lysozyme, lactoferrin and immunoglobulins, and furthermore the number of immunoglobulins is compatible with human ones. Goat milk components have a higher degree of assimilability as compared to cow milk. Its main protein is β-casein, with total protein content depending on the αs1-casein genetic variant. Goats with the ‘0’ variant do not synthesize this allergenic protein. Clinical and immunochemical studies indicate, however, that it cannot be a substitute for cow milk without the risk of an anaphylactic reaction.

  4. Production of Volatile Compounds in Reconstituted Milk Reduced-Fat Cheese and the Physicochemical Properties as Affected by Exopolysaccharide-Producing Strain

    Directory of Open Access Journals (Sweden)

    Weijun Wang

    2012-12-01

    Full Text Available The application of the exopolysaccharide-producing strains for improving the texture and technical properties of reduced-fat cheese looks very promising. Streptococcus thermophilus TM11 was evaluated for production of reduced-fat cheese using reconstituted milk powder (CRMP. The physicochemical analysis of fresh and stored cheeses showed that this strain slightly increased moisture content resulting in cheese with higher yield and lower protein content compared to the direct acidified cheese. The volatiles of cheese were determined by SPME and GC equipped with a mass spectrometer. The results indicated that the major compounds included aldehydes, ketones and acids, whereas, alcohols and branched-chain aldehydes that contribute to exciting and harsh flavors were not found in CRMP. By the textural profile analysis, we found the cheese made with S. thermophilus TM11 had lower cohesiveness, resilience and higher adhesiveness than the direct acidified cheese, and had similar hardness. Further, S. thermophilus TM11 greatly changed the protein matrix with more opened cavities according to observation by scanning electron microscopy. Consequently, use of S. thermophilus TM11 could endow CRMP with the novel and suitable flavor properties and improved texture quality.

  5. The overall and fat composition of milk of various species

    Directory of Open Access Journals (Sweden)

    Vesna Gantner

    2015-11-01

    Full Text Available Milk, an essential source of offspring nourishment, varies in it’s composition and properties significantly across species. In human nutrition, fresh milk and dairy products are valuable sources of protein, fat and energy, and are an important part of daily meals. Most of the world’s milk production (85 % comes from cows followed by buffaloes, goats, ewes, mares and donkeys. However milk related food allergies in infants may be a reason for health problems and may cause a decrease in milk. The objective of this paper was to give an overview of the overall composition of milk and fat from different species in comparison to women milk. Regarding the overall milk composition remarkable differences in energy content, fat, lactose, protein and ash of the various milks were found, but also some similarities among milk from ruminants and non-ruminants were detected. The structures of fat globule membranes were similar among non-ruminants and women milk, while the milk fat globule structure in ruminants differed significantly. The size of fat globules was significantly different between species and highly correlated to the milk fat content, regardless of the specie. The amount of triacylglycerols was notably higher, while the amount of free fatty acids and phospholipids was notably lower in milk from ruminants and women compared to milk from mares and donkeys. The triacylglycerol structure in women and non-ruminantsˈ was similar. The percentage of saturated and monounsaturated fatty acids was lower, while the unsaturated fatty acid content was higher in milk from non-ruminants, with a remarkably higher percentage of C-18:2 and C-18:3. The cholesterol content was similar in women and ruminantsˈ milk, but lower in that of non-ruminants. This review indicates that milk from non-ruminants could be more suitable for human nourishment than milk from ruminants.

  6. Retrospective analysis of a listeria monocytogenes contamination episode in raw milk goat cheese using quantitative microbial risk assessment tools.

    Science.gov (United States)

    Delhalle, L; Ellouze, M; Yde, M; Clinquart, A; Daube, G; Korsak, N

    2012-12-01

    In 2005, the Belgian authorities reported a Listeria monocytogenes contamination episode in cheese made from raw goat's milk. The presence of an asymptomatic shedder goat in the herd caused this contamination. On the basis of data collected at the time of the episode, a retrospective study was performed using an exposure assessment model covering the production chain from the milking of goats up to delivery of cheese to the market. Predictive microbiology models were used to simulate the growth of L. monocytogenes during the cheese process in relation with temperature, pH, and water activity. The model showed significant growth of L. monocytogenes during chilling and storage of the milk collected the day before the cheese production (median increase of 2.2 log CFU/ml) and during the addition of starter and rennet to milk (median increase of 1.2 log CFU/ml). The L. monocytogenes concentration in the fresh unripened cheese was estimated to be 3.8 log CFU/g (median). This result is consistent with the number of L. monocytogenes in the fresh cheese (3.6 log CFU/g) reported during the cheese contamination episode. A variance-based method sensitivity analysis identified the most important factors impacting the cheese contamination, and a scenario analysis then evaluated several options for risk mitigation. Thus, by using quantitative microbial risk assessment tools, this study provides reliable information to identify and control critical steps in a local production chain of cheese made from raw goat's milk.

  7. Physico-chemical characterisation of some samples of fresh milk and milk powder

    Directory of Open Access Journals (Sweden)

    Soceanu Alina

    2015-12-01

    Full Text Available Milk consumption is important in the diet of all age groups because it provides important nutrients that are essential for humans. Children are the largest consumers of milk, thus, it’s very important that milk is free of toxic compounds that can be harmful for humans. Aim of the study was to determine the physico-chemical characteristics of some samples of milk powder for different stage of baby growing and for some samples of fresh milk: raw cow’s milk, milk trade and UHT type. The following physico-chemical properties: density, pH, acidity, the presence of acetone, enzymes, antiseptics, dry substance, the ash, total fat, saponification and peroxide index, total nitrogen and protein content were determined. Comparing the values of acidity for analyzed samples it can be concluded that the powder milk acidity value is much lower than the fresh milk. The presence of antiseptics and acetone was not identified, and amylase and peroxidase were found only in raw cow's milk. The highest protein content was found for milk powder (27.22%.

  8. [The direct donation of human milk in neonatology].

    Science.gov (United States)

    Buffin, Rachel

    2012-01-01

    The superiority of human milk over its substitutes is no longer questioned, especially for the feeding of premature babies or newborns hospitalised in neonatology. Milk banks organise the collection, conservation, treatement and distribution of human milk. The objective is however to encourage the direct donation of raw milk, avoiding the need for freezing and pasteurisation, in order to preserve its properties as best as possible.

  9. Subclinical mastitis in goats is associated with upregulation of nitric oxide-derived oxidative stress that causes reduction of milk antioxidative properties and impairment of its quality.

    Science.gov (United States)

    Silanikove, Nissim; Merin, Uzi; Shapiro, Fira; Leitner, Gabriel

    2014-01-01

    The aim of this study was to verify the existence of a nitric oxide (NO) cycle in goat milk and to study how changes in it affect milk composition during subclinical mastitis. Fifteen lactating dairy goats in which one udder-half was free from bacterial infection and the contra-lateral one was naturally infected with various species of coagulase-negative staphylococci were used. In comparison to uninfected glands, subclinical mastitis was associated with a decrease in milk yield, lactose concentration, and curd yield and an increase in nitrite and nitrate concentrations and with measurements reflecting increased formation of NO-derived free-radical nitrogen dioxide. The occurrence of NO cycling in goat milk was largely confirmed. The increase in the NO-derived stress during subclinical infection was not associated with significant increase in oxidatively modified substances, 3-nitrotyrosine, and carbonyls on proteins, but with increased levels of peroxides on fat. However, the relatively modest nitrosative stress in subclinically infected glands was associated with significant reduction in total antioxidant capacity and vitamin C levels in milk. We concluded that subclinical mastitis in goats caused by coagulase-negative staphylococci imposes negative changes in milk yield, milk quality for cheese production, and negatively affects the nutritional value of milk as food. Thus, subclinical mastitis in goats should be considered as a serious economic burden both by farmers and by the dairy industry. Copyright © 2014 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  10. Effect of simulated milk fat with different melting points on the physiochemical properties of concentrated milk protein by spray drying%不同熔点乳脂模拟物对浓缩乳蛋白喷雾干燥粉理化性质的影响

    Institute of Scientific and Technical Information of China (English)

    张洪超; 胡锦华; 郭宏慧; 周鹏

    2015-01-01

    The effect of milk fat with different melting points on milk powders' physicochemical properties was investigated.The milk fat and fatty acid components in commercial concentrated milk protein were analyzed to select the best simulations and using spray dry to obtained the milk powder.The surface fat concentration,microstructure and protein dissolution behavior of the powders were measured.Compared with new spray-dried MPC,milk powders containing esters had a rough surface with fat layer and had a porous wall.The surface fat contents varied with esters' melting point,the higher melting point,the higher content.Protein dissolution behavior different with each other and the dissolution rate were slower than that of spray dried MPC.%文中探讨了不同熔点乳脂组成对浓缩乳蛋白干粉理化性质的影响.首先利用气相色谱技术分析商业浓缩乳蛋白(milk protein concentrate,MPC)的脂肪酸组成,并结合乳脂肪的熔点(melting point,MP)特征选取不同熔点的脂肪酸甲酯模拟乳脂肪,其次采用喷雾干燥技术制备含不同乳脂模拟物的加脂乳粉,并对其表面含脂量、微观结构和蛋白质溶解行为进行分析.研究发现:与商业MPC重新喷雾干燥后表面光滑和内壁致密的结构相比,加脂的乳粉则表面粗糙、多孔且内壁疏松,表面还可观察到脂肪层;加脂乳粉的表面含脂量随着所加甲酯熔点的升高逐渐增加;不同甲酯的添加使得加脂乳粉的蛋白质溶解行为存在差异,而且与MPC相比,不同加脂乳粉中蛋白质溶出速率均变得缓慢.

  11. Cow's milk and children

    Science.gov (United States)

    Milk and children; Cow’s milk allergy - children; Lactose intolerance - children ... You may have heard that cow's milk should not be given to babies younger than 1 year old. This is because cow's milk doesn't provide enough of certain ...

  12. Contribution of macrophages to proteolysis and plasmin activity in ewe bulk milk.

    Science.gov (United States)

    Caroprese, M; Marzano, A; Schena, L; Marino, R; Santillo, A; Albenzio, M

    2007-06-01

    A total of 225 bulk sheep milk samples were collected from 5 intensively managed flocks during early, mid, and late lactation to assess the contribution of macrophages to the regulation of the plasmin-plasminogen system. Samples were analyzed for composition, somatic cell counts, milk renneting characteristics, and for plasmin (PL), plasminogen (PG), and plasminogen activators (PA) activities. Isolation of macrophages from milk was performed using a magnetic positive separation and mouse antiovine macrophage antibody; separated cells were lysed by several freeze-thaw cycles, and activity of urokinase PA (u-PA) was determined. Plasmin activity decreased during lactation (42.06 +/- 0.66, early; 31.29 +/- 0.66, mid; 28.19 +/- 0.66 U/mL, late). The reduction in PL activity recorded in the mid and late lactation milk matched the increase in PG:PL ratio. The activity of PA increased throughout lactation; the highest value being recorded in the late lactation milk (260.20 +/- 8.66 U/mL). Counts of isolated and concentrated macrophages were higher in early and mid lactation milk (3.89 +/- 0.08 and 3.98 +/- 0.08 log10 cells/mL, respectively) than in late lactation milk (3.42 +/- 0.08 log10 cells/mL). Stage of lactation did not influence the activity of u-PA detected in isolated macrophages. The activity of u-PA associated with isolated milk macrophages only minimally contributed to total PA activity detected in milk. Proteolytic enzymes, associated with isolated macrophages, act on alpha-casein hydrolysis, as shown by urea-PAGE electrophoresis analysis. Somatic cell counts did not exceed 600,000 cells/mL, and this threshold can be considered a good index of health status of the flock and of the ability of milk to being processed. Our results lend support to the hypothesis that macrophages in ewe bulk milk from healthy flocks only slightly contribute to the activation of the PL-PG system.

  13. Relationship of goat milk flow emission variables with milking routine, milking parameters, milking machine characteristics and goat physiology.

    Science.gov (United States)

    Romero, G; Panzalis, R; Ruegg, P

    2017-04-10

    The aim of this paper was to study the relationship between milk flow emission variables recorded during milking of dairy goats with variables related to milking routine, goat physiology, milking parameters and milking machine characteristics, to determine the variables affecting milking performance and help the goat industry pinpoint farm and milking practices that improve milking performance. In total, 19 farms were visited once during the evening milking. Milking parameters (vacuum level (VL), pulsation ratio and pulsation rate, vacuum drop), milk emission flow variables (milking time, milk yield, maximum milk flow (MMF), average milk flow (AVMF), time until 500 g/min milk flow is established (TS500)), doe characteristics of 8 to 10 goats/farm (breed, days in milk and parity), milking practices (overmilking, overstripping, pre-lag time) and milking machine characteristics (line height, presence of claw) were recorded on every farm. The relationships between recorded variables and farm were analysed by a one-way ANOVA analysis. The relationships of milk yield, MMF, milking time and TS500 with goat physiology, milking routine, milking parameters and milking machine design were analysed using a linear mixed model, considering the farm as the random effect. Farm was significant (Pvariables. Milk emission flow variables were similar to those recommended in scientific studies. Milking parameters were adequate in most of the farms, being similar to those recommended in scientific studies. Few milking parameters and milking machine characteristics affected the tested variables: average vacuum level only showed tendency on MMF, and milk pipeline height on TS500. Milk yield (MY) was mainly affected by parity, as the interaction of days in milk with parity was also significant. Milking time was mainly affected by milk yield and breed. Also significant were parity, the interaction of days in milk with parity and overstripping, whereas overmilking showed a slight tendency

  14. Donor human milk versus mother's own milk in preterm VLBWIs: a case control study.

    Science.gov (United States)

    Giuliani, F; Prandi, G; Coscia, A; Cresi, F; Di Nicola, P; Raia, M; Sabatino, G; Occhi, L; Bertino, E

    2012-01-01

    As for term infants, over the past decades there has been increasing evidence of the benefits of human milk in the feeding of Very Low Birth Weight Infants (VLBWI), influencing not only short-term health outcomes but also long-term neurodevelopmental, metabolic outcomes, and growth. Mother's own milk is the first choice for all neonates including preterm infants, when it is unavailable or in short supply, pasteurized donor breast milk offers a safe alternative and is considered the next best choice. The main aim of this case-control retrospective analysis was to evaluate short term advantages of mother's own milk as a sole diet compared to donor milk as a sole diet, in terms of growth, antiinfectious properties, feeding tolerance, NEC and ROP prevention in a population of VLBWI born in a tertiary center. We did not find significant differences in clinical outcome from mother's own milk compared with pasteurized donor milk. Only a slight and statistically not significant difference in growth could be observed, in favour of maternal milk. We conclude that the maximum effort should always be put in supporting and promoting breastfeeding and donor milk used not only as an alternative to mother's milk but also as a breastfeeding promotion and support strategy.

  15. Effect of soya milk on nutritive, antioxidative, reological and textural properties of chocolate produced in a ball mill

    OpenAIRE

    Zarić Danica B.; Pajin Biljana S.; Rakin Marica B.; Šereš Zita I.; Dokić Ljubica P.; Tomić Jelena M.

    2011-01-01

    Chocolate is a complex rheological system in which non-fat cocoa particles and sugar particles are enveloped by crystal matrix of cocoa butter. Physical properties of chocolate depend on ingredient composition, method of production and properly performed pre-crystallization phase. In this work, chocolate was produced in an unconventional way, i.e. in a ball mill applying variable refining time (30, 60 and 90 min) and pre-crystallization temperature in chocolate masses (26, 28 and 30⁰C)....

  16. Milk nutritional components and physic-chemical properties of ‘Hexi cashmare goat’%‘河西绒山羊’乳营养成分及理化性质研究

    Institute of Scientific and Technical Information of China (English)

    邵尊亚; 雷赵民; 宫旭胤; 魏玉兵; 刘婷; 童建伟

    2014-01-01

    One hundrede ‘Hexi cashmare goat’in 5 parities were selected to collect milk samples,con-taining 30th day's milk and 100th day's milk,the milk nutritional components and physic-chemical proper-ties were studied on different parity and different lactation time.The results showed that the contents of milk protein of 1st,2nd,3rd parity was separately higher than that of 4th,5th parity significantly (P<0.05).The contents of milk fat,total solids of 1st,2nd,4th parity was separately higher than that of 5th parity significantly (P<0.05),the 3rd parity was higher than that of 1st,2nd,4th parity significantly (P<0.05).The contents of milk non-fat solids of 2nd,3rd parity was separately higher than that of 1st,4th,5th parity significantly (P<0.05).The contents of milk protein,total solids of 30th day were lower than that of 100th day significantly (P<0.05).Physic-chemical properties,the milk acidity of 1st,2nd,3rd parity was separately lower than that of 4th,5th parity significantly (P<0.05),the milk acidity of 30th day was lower than that of 100th day significantly (P<0.05).%选择‘河西绒山羊’5个胎次共100只,采集产后第30天、第100天的乳样,研究不同胎次和不同泌乳时间羊乳的营养成分及理化性质.结果表明:‘河西绒山羊’乳中粗蛋白含量第1、2、3胎均显著高于第4、5胎(P<0.05),乳中粗脂肪含量、总固形物含量第1、2、4胎均显著高于第5胎(P<0.05),第3胎显著高于第1、2、4胎(P<0.05),乳中非脂固形物含量第2、3胎均显著高于第1、4、5胎(P<0.05).乳粗蛋白含量、总固形物含量产后第30天显著低于产后第100天(P<0.05).乳酸度值第1、2、3胎均显著低于第4、5胎(P<0.05),产后第30天乳酸度值显著低于产后第100天(P<0.05).

  17. Effect of solar radiation and flaxseed supplementation on milk production and fatty acid profile of lactating ewes under high ambient temperature.

    Science.gov (United States)

    Caroprese, M; Albenzio, M; Bruno, A; Fedele, V; Santillo, A; Sevi, A

    2011-08-01

    The objectives of this study were to evaluate the effects of protection from solar radiation and whole flaxseed supplementation on milk yield and milk fatty acid profile in lactating ewes exposed to high ambient temperature. The experiment was conducted during summer and involved 40 ewes divided into 4 groups. The ewes were either exposed (not offered shade) or protected from solar radiation (offered shade). For each solar radiation treatment, ewes were supplemented with whole flaxseed or not. Milk samples from each ewe were collected at the morning and afternoon milking every week, and analyzed for pH, total protein, casein, fat, and lactose content, somatic cell count, and renneting parameters (clotting time, rate of clot formation, and clot firmness after 30 min). At the beginning of the experiment, and then at d 23 and 44, milk samples were analyzed for milk fatty acids using gas chromatography. Flaxseed supplementation significantly increased milk yield, fat, protein, and casein yields, and somatic cell count, and increased fat and lactose contents of milk. A decrease of saturated fatty acids from C6:0 to C16:0 and an increase of C18:1 trans-11 and C18:2 cis-9,trans-11 was observed in milk from flaxseed-supplemented ewes. Flaxseed supplementation decreased saturated fatty acids content and increased total monounsaturated fatty acids content, the total content of isomers of conjugated linoleic acid, and polyunsaturated fatty acids content in milk. Flaxseed also increased the α-linolenic acid content of milk. As a result, milk from supplemented groups showed an increase in n-3 fatty acid content. Flaxseed supplementation decreased short-chain and medium-chain fatty acids, and increased long-chain fatty acid content of milk. On average, flaxseed supplementation increased the C18:2 cis-9,trans-11/C18:1 trans-11 Δ(9)-desaturase index starting from d 23 of the experiment, in correspondence with the highest C18:2 cis-9,trans-11 content of milk from flaxseed

  18. 超高压射流灭菌对牛奶理化特性的影响%Effect on phy-chemical properties of sterilization milk by ultra-high pressure jet technology

    Institute of Scientific and Technical Information of China (English)

    罗兰; 王盛民; 吴贞贞; 黄义娜; 王懿萍; 张小荣; 陈波

    2011-01-01

    利用超高压射流对撞式/碰撞式技术处理液态奶,考察其相对密度、滴定酸度、pH值、灰分碱度、浊度、颗粒粒径等理化性质.结果表明,超高压射流处理后,液态奶的灰分碱度及压力≥200 MPa时滴定酸度均符合灭菌乳国家标准(GB5408.2-1999);相对密度保持不变;浊度呈上升趋势;对撞方式均质效果明显优于碰撞方式.超高压射流处理牛奶的最佳工艺为200 MPa对撞方式处理.该研究为超高压射流杀菌奶的后续深入研究奠定了基础.%Liquid milk was treated by ultra-high pressure jet(clash/collision), in order to study its phy-chemic(** )rties of relative density,titrable acidity, PH, ash alkalinity, turbidity, partical size.The result indicates that after liquid milk treated by(** )h pressure jet,ash alkalinity is accordance with the national standard of sterilized milk (GB5408.2-1999) ,and it is also with titrable acidity(** )the pressure was no less than 200 MPa.Relative density remains the same, while turbidity has a rising trend.The homogenizing effect(** )sh(** )ent is obviously superior to collision.Thus, the best technology of of ultra-high pressure jet sterilization is clash type at 200 MPa.T(** )rch of the phy-chemical properties of liquid milk establishes the foundation for the further study of sterilization milk by ultra-high pressure jet technology.

  19. STABILITY OF WATER-IN-OIL-IN-WATER MULTIPLE EMULSIONS: INFLUENCE OF THE INTERFACIAL PROPERTIES OF MILK FAT GLOBULE MEMBRANE

    OpenAIRE

    J.G. Dzul-Cauich; C. Lobato-Calleros; J.P. Pérez-Orozco; J. Alvarez-Ramirez; E.J. Vernon-Carter

    2013-01-01

    The interfacial shear viscosity (r¡iJlt) and the creep compliance-time (J(t» behavior of mi1k fat globule membrane (MFGM) films (4, 5 and 6% w/w) formed at the water-oil interface were evaluated. Films with higher MFGM concentration displayed higher r¡int and interfacial viscoelastic properties. When esters of polyglycerol and polyriciniolate fatty acids (PGPR) were added to the oil phase, a competitive adsorption at the interface took place between PGPR and MFGM which caused a decrease in th...

  20. Production, yield and characteristics of Feta and Domiati type cheeses produced from goat´s milk

    Directory of Open Access Journals (Sweden)

    Ida Drgalić

    2002-04-01

    Full Text Available Brined Feta and Domiati type cheeses were produced from whole goat´s milk. Different types of production were used; with and without goat´s milk acidification with citric acid. The effect of calcium chloride addition was also examined. Renneting of goat´s milk with 0.03% renilase was conducted at 40°C for Domiati type cheese and at 30°C for Feta type cheese. Additives (citric acid and calcium chloride presence had no effect on reneting time for Feta type cheeses while citric acid addition significantly reduced reneting time for Domiati type cheeses. Domiati type cheeses possessed softer consistency, lower acidity, lower protein and fat content than Feta type cheeses. The yield of Domiati type cheeses was approximately 18.37% higher than of Feta type cheeses. Ripening of both types of cheeses was conducted in the brine with 10% sodium chloride at 12°C for 14 days. All cheese samples had lower protein, fat and calcium content in comparison with quality of cheeses before ripening in a brine. This especially occurred in Feta type cheeses. Sensory evaluation of analysed type of cheese was determined at 7th and 14th day of ripening. Better sensory scores are obtained for both types of cheeses after 14 days of ripening, when flavour and taste improvements were significantly higher. The best scores were obtained for Domiati cheese samples from unacidified goat´s milk, regardles of calcium chloride addition.

  1. Major advances in fresh milk and milk products: fluid milk products and frozen desserts.

    Science.gov (United States)

    Goff, H D; Griffiths, M W

    2006-04-01

    Major technological advances in the fluid milk processing industry in the last 25 yr include significant improvements in all the unit operations of separation, standardization, pasteurization, homogenization, and packaging. Many advancements have been directed toward production capacity, automation, and hygienic operation. Extended shelf-life milks are produced by high heat treatment, sometimes coupled with microfiltration or centrifugation. Other nonthermal methods have also been investigated. Flavored milk beverages have increased in popularity, as have milk beverages packaged in single-service, closeable plastic containers. Likewise, the frozen dairy processing industry has seen the development of large-capacity, automated processing equipment for a wide range of products designed to gain market share. Significant advancements in product quality have been made, many of these arising from improved knowledge of the functional properties of ingredients and their impact on structure and texture. Incidents of foodborne disease associated with dairy products continue to occur, necessitating even greater diligence in the control of pathogen transmission. Analytical techniques for the rapid detection of specific types of microorganisms have been developed and greatly improved during this time. Despite tremendous technological advancements for processors and a greater diversity of products for consumers, per capita consumption of fluid milk has declined and consumption of frozen dairy desserts has been steady during this 25-yr period.

  2. Differences of some indicators of raw milk properties and especially mineral composition between small ruminants as compared to cows in the Czech Republic

    Directory of Open Access Journals (Sweden)

    Oto Hanuš

    2008-01-01

    Full Text Available Sheep and goat farming is returning back into the Czech Republic (CR because of positive effects of alternative milk consumption on human health. Especially the elements Ca and Mg are important for nutrition. Paper presents the comparison of mineral milk composition of goats (White short–haired–W, n = 60, sheep (Tsigai–C, n = 60 and cows (Holstein–H, n = 36; Czech Fleckvieh–B, n = 93. Cow milk results were considered as reference. The herds were kept at altitude 260 m (H, 360 m (B, and 572 m above sea level (W, C with total precipitation 449, 700 and 1200 mm per year and mean air temperatures 9.6, 7.0 and 3.7 °C. Bulk milk samples (4–8 animals in sample from the first two thirds of the lactation and the winter and summer season were investigated. Goat milk freezing point differed from other species (P < 0.001, −0.6048 for C < −0.5544 W < −0.5320 H < −0.5221 °C for B. Cow milk Ca values were comparable to former results although milk yield (MY was higher. Along lower MY the Ca was higher (1299.6 > 1172.0 mg . kg−1; P < 0.001 in B than H, similar trend was in Mg (122.0 > 107.4 mg . kg−1; P<0.001. Differences (P > 0.05 between species were in Ni and also mostly in Cu. Iodine results differed between species but not between cow breeds (P < 0.001; 462.8 H and 434.9 B > 126.0 W and 164.2 μg . l−1 C. It could be explainable by using of I disinfection at teat treatment in cows and absence of treatment in small ruminants. Macroelements were mostly highest (Ca, P, Na, Mg in sheep milk, with exception of K. Phosphorus values (950.1 H, 1016.9 B, 1042.6 W and 1596.7 mg . kg−1 C in species were linked with crude or true protein and casein values. Small ruminant milk could be good source of minerals for human nutrition, especially in the case of Ca and Mg of sheep and goat milk.

  3. Physical properties of acid milk gels prepared at 37 degrees C up to gelation but at different incubation temperatures for the remainder of fermentation.

    Science.gov (United States)

    Peng, Y; Horne, D S; Lucey, J A

    2010-05-01

    We investigated the effect of altering temperature immediately after gels were formed at 37 degrees C. We defined instrumentally measurable gelation (IMG) as the point at which gels had a storage modulus (G') > or = 5Pa. Gels were made at constant incubation temperature (IT) of 37 degrees C up to IMG, and then cooled to 30 or 33.5, or heated to 40.5 or 44 degrees C, at a rate of 1 degrees C/min and maintained at those temperatures until pH 4.6. Control gel was made at 37 degrees C (i.e., no temperature change during gelation/gel development). Gel formation was monitored using small strain dynamic oscillatory rheology, and the resulting structure and physical properties at pH 4.6 were studied by fluorescence microscopy, large deformation rheology, whey separation (WS), and permeability (B). A single strain of Streptococcus thermophilus was used to avoid variations in the ratios of strains that could have resulted from changes in temperature during fermentation. Total time required to reach pH 4.6 was similar for samples made at constant IT of 37 degrees C or by cooling after IMG from 37 to either 30 or 33.5 degrees C, but gels heated to 40 or 44 degrees C needed less time to reach pH 4.6. Cooling gels after IMG resulted in an increase in G' values at pH 4.6, a decrease in LT(max), WS, and B, and an increase in the area of protein aggregates of micrographs compared with the control gel made at constant IT of 37 degrees C. Heating gels after IMG resulted in a decrease in G' values at pH 4.6 and an increase in LT(max) values and WS. The physical properties of acid milk gels were dominated by the temperature profile during the gel-strengthening phase that occurs after IMG. This study indicates that the final properties of yogurt greatly depend on the environmental conditions (e.g., temperature, time/rate of pH change) experienced by the casein particles/clusters during the critical early gel development phase when bonding between and within particles is still labile

  4. [Cow's milk protein allergy through human milk].

    Science.gov (United States)

    Denis, M; Loras-Duclaux, I; Lachaux, A

    2012-03-01

    Cow's milk protein allergy (CMPA) is the first allergy that affects infants. In this population, the incidence rate reaches 7.5%. The multiplicity and aspecificity of the symptoms makes its diagnosis sometimes complicated, especially in the delayed type (gastrointestinal, dermatological, and cutaneous). CMPA symptoms can develop in exclusively breastfed infants with an incidence rate of 0.5%. It, therefore, raises questions about sensitization to cow's milk proteins through breast milk. Transfer of native bovine proteins such as β-lactoglobulin into the breast milk is controversial: some authors have found bovine proteins in human milk but others point to cross-reactivity between human milk proteins and cow's milk proteins. However, it seems that a small percentage of dietary proteins can resist digestion and become potentially allergenic. Moreover, some authors suspect the transfer of some of these dietary proteins from the maternal bloodstream to breast milk, but the mechanisms governing sensitization are still being studied. Theoretically, CMPA diagnosis is based on clinical observations, prick-test or patch-test results, and cow's milk-specific IgE antibody concentration. A positive food challenge test usually confirms the diagnosis. No laboratory test is available to make a certain diagnosis, but the detection of eosinophil cationic protein (ECP) in the mother's milk, for example, seems to be advantageous since it is linked to CMA. Excluding cow's milk from the mother's diet is the only cure when she still wants to breastfeed. Usually, cow's milk proteins are reintroduced after 6 months of exclusion. Indeed, the prognosis for infants is very good: 80% acquire a tolerance before the age of 3 or 4 years. Mothers should not avoid dairy products during pregnancy and breastfeeding as preventive measures against allergy.

  5. MICROBIOLOGICAL CHARACTERISTICS OF MILK FROM DONKEYS FARMED IN CAMPANIA REGION: PRELIMINARY RESULTS

    Directory of Open Access Journals (Sweden)

    E. Sarno

    2012-08-01

    Full Text Available Interest in donkey’s milk destined to human consumption is increasing owing to its complex composition and unique functional properties. The microbiological profile of donkeys’ raw milk was investigated. Individual donkey milk samples were collected from 8 asses after mechanical milking and filtration in a farm of Campania region. A total of 133 samples were analyzed. Total plate count bacteria and Enterobacteriaceae were enumerated. Other microbiological characteristics were monitored as established by legislation in force on the sale of raw milk. Results showed a low contamination level of the raw milk in accordance with other authors. No correlations were evidenced between milk contamination and lactation stage.

  6. Influence of intramammary infection of a single gland in dairy cows on the cow's milk quality.

    Science.gov (United States)

    Bezman, Dror; Lemberskiy-Kuzin, Liubov; Katz, Gil; Merin, Uzi; Leitner, Gabriel

    2015-08-01

    Intramammary infection (IMI), comprises a group of costly diseases affecting dairy animals worldwide. Many dairy parlours are equipped with on-line computerised data acquisition systems designed to detect IMI. However, the data collected is related to the cow level, therefore the contribution of infected glands to the recorded parameters may be over estimated. The present study aimed at evaluating the influence of single gland IMI by different bacteria species on the cow's overall milk quality. A total of 130 cows were tested 239 times; 79 cows were tested once and the others were examined 2-8 times. All of the analysed data refer to the number of tests performed, taking into account the repeated testing of the same cows. Of the cows tested ~50% were free of infection in all 4 glands and the others were infected in one gland with different coagulase negative staphylococci (CNS), Streptococcus dysgalactiae, or were post infected with Escherichia coli (PIEc), i.e., free of bacterial infection at the time of sampling but 1-2 months after clinical infection by E. coli. Overall, infection with bacteria had significant effects on somatic cell count (SCC) and lactose concentration. Examining each bacterium reveals that the major influence on those parameters was the sharp decrease in lactose in the PIEc and curd firmness in PIEc and Strep. Individual gland milk production decreased ~20% in Strep. dysgalactiae- and ~50% in PIEc-infected glands with respect to glands with no bacterial findings. Significant differences were found in lactose, SCC, rennet clotting time and curd firmness in the milk of infected glands and among those, these parameters were significantly higher in Strep. dysgalactiae and PIEc than in CNS infected cows. The current results using quarter-milking reinforces the importance of accurate IMI detection in relation to economic and welfare factors, and moreover, emphasises the need for technical sensing and constant reporting to the farmer about changes

  7. Selenium content of milk and milk products of Turkey. II.

    Science.gov (United States)

    Yanardağ, R; Orak, H

    1999-04-01

    Selenium content of 1028 milk and milk products of Turkey are presented in this study. The selenium content of human milk (colostrum, transitional, and mature milk), various kinds of milk [cow, sheep, goat, buffalo, paper boxes (3%, 1.5%, 0.012% fat), bottled milk, condensed milk (10% fat), mineral added milk (1.6%), and banana, strawberry, and chocolate milk] and milk products (kefir, yogurt, Ayran, various cheese, coffee cream, ice cream, butter, margarine, milk powder, and fruit yogurt) in Turkey were determined by a spectrofluorometric method. The selenium levels of cow milks collected from 57 cities in Turkey were also determined. Selenium levels in cow milk varied with geographical location in Turkey and were found to be lowest for Van and highest for Aksaray. The results [milk (cow, sheep, goat, buffalo and human) and milks products] were compared with literature data from different countries.

  8. Role of milk protein-based products in some quality attributes of goat milk yogurt.

    Science.gov (United States)

    Gursel, A; Gursoy, A; Anli, E A K; Budak, S O; Aydemir, S; Durlu-Ozkaya, F

    2016-04-01

    Goat milk yogurts were manufactured with the fortification of 2% (wt/vol) skim goat milk powder (SGMP), sodium caseinate (NaCn), whey protein concentrate (WPC), whey protein isolate (WPI), or yogurt texture improver (YTI). Yogurts were characterized based on compositional, microbiological, and textural properties; volatile flavor components (with gas chromatography); and sensory analyses during storage (21d at 5 °C). Compared with goat milk yogurt made by using SGMP, the other goat milk yogurt variants had higher protein content and lower acidity values. Goat milk yogurts with NaCn and WPC, in particular, had better physical characteristics. Using WPI caused the hardest structure in yogurt, leading to higher syneresis values. Acetaldehyde and ethanol formation increased with the incorporation of WPI, WPC, or YTI to yogurt milk. The tyrosine value especially was higher in the samples with NaCn and YTI than in the samples with WPC and WPI. Counts of Streptococcus thermophilus were higher than the counts of Lactobacillus delbrueckii ssp. bulgaricus, possibly due to a stimulatory effect of milk protein-based ingredients other than SGMP on the growth of S. thermophilus. Yogurt with NaCn was the best accepted among the yogurts. For the parameters used, milk protein-based products such as NaCn or WPC have promising features as suitable ingredients for goat milk yogurt manufacture.

  9. Validation of modified milk reference sample in terms of its suitability for infra-red analysis calibration via evaluation of physical properties

    Directory of Open Access Journals (Sweden)

    Oto Hanuš

    2010-01-01

    Full Text Available Routine milk analyses using the efficient indirect infra-red method are important for the milk food chain quality. The reliability of the results depends on the calibration quality. It is important to use a relevant set of reference calibration samples (RCSs. RCSs with right range of values can be prepared using various methods. This paper was aimed to balance the impacts of dilution for decrease of main components in RCSs because of minimal change of matrix interference effects. Cow milk samples (MSs were diluted (4/1 using distilled water, NaCl solution and a solution with specific composition (SC; because of disturbance in the balance of the milk matrix (NaCl 1.145; KCl 0.849; K2HPO4 1.8463; citric acid 1.7; urea 0.3 g / l for reduction in main milk components. Fat (F, crude protein (CP, lactose (L, milk freezing point (MFP, osmolality (OS and electrical conductivity (EC were measured in all (original as well as modified MSs. The lowest MFP and OS were in the original milk −0.5559 °C and 274.5 mOsmol/kg. The MFP was increased to −0.4369 °C and osmolality decreased to 217.83 ­mOsmol/kg by the addition of water. The MFP was decreased (−0.4903 °C and returned to original milk value by the addition of NaCl solutin. MFP was −0.4788 °C due to SC addition. The decrease was less than for NaCl. The ability of other SC components (K2HPO4, KCl, citric acid and urea to MFP decrease is less than for NaCl solution. EC was highest for NaCl set 4.69 mS / cm, EC for SC was 4.48 mS / cm (P < 0.001. The original MSs set showed EC 4.27 mS / cm. The SC was the nearest to original MSs in terms of total mineral composition. ECs for both modifications differed (P < 0.001 from original MSs. The procedure is applicable for balance of interference effects of milk matrix because of relevant calibration.

  10. Microorganisms in human milk: lights and shadows.

    Science.gov (United States)

    Civardi, Elisa; Garofoli, Francesca; Tzialla, Chryssoula; Paolillo, Piermichele; Bollani, Lina; Stronati, Mauro

    2013-10-01

    Human milk has been traditionally considered germ free, however, recent studies have shown that it represents a continuous supply of commensal and potentially probiotic bacteria to the infant gut. Mammary microbioma may exercise anti-infective, anti-inflammatory, immunomodulatory and metabolic properties. Moreover human milk may be a source of pathogenic microorganism during maternal infection, if contaminated during expression or in case of vaccination of the mother. The non-sterility of breast milk can, thus, be seen as a protective factor, or rarely, as a risk factor for the newborn.

  11. Milk-alkali syndrome

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/000332.htm Milk-alkali syndrome To use the sharing features on this page, please enable JavaScript. Milk-alkali syndrome is a condition in which there ...

  12. Cow's milk - infants

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/article/002448.htm Cow's milk - infants To use the sharing features on this ... old, you should not feed your baby cow's milk, according to the American Academy of Pediatrics (AAP). ...

  13. Breast milk jaundice

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/article/000995.htm Breast milk jaundice To use the sharing features on this ... otherwise healthy, the condition may be called "breast milk jaundice." Causes Bilirubin is a yellow pigment that ...

  14. Breastfeeding and Breast Milk

    Science.gov (United States)

    ... Clinical Trials Resources and Publications Breastfeeding and Breast Milk: Condition Information Skip sharing on social media links Share this: Page Content Breastfeeding and Breast Milk: Condition Information​ ​​Breastfeeding, also called nursing, is the ...

  15. Real-time evaluation of milk quality as reflected by clotting parameters of individual cow's milk during the milking session, between day-to-day and during lactation.

    Science.gov (United States)

    Leitner, Gabriel; Merin, Uzi; Jacoby, Shamay; Bezman, Dror; Lemberskiy-Kuzin, Liubov; Katz, Gil

    2013-09-01

    Real-time analysis of milk coagulation properties as performed by the AfiLab™ milk spectrometer introduces new opportunities for the dairy industry. The study evaluated the performance of the AfiLab™ in a milking parlor of a commercial farm to provide real-time analysis of milk-clotting parameters -Afi-CF for cheese manufacture and determine its repeatability in time for individual cows. The AfiLab™ in a parlor, equipped with two parallel milk lines, enables to divert the milk on-line into two bulk milk tanks (A and B). Three commercial dairy herds of 220 to 320 Israeli Holstein cows producing ∼11 500 l during 305 days were selected for the study. The Afi-CF repeatability during time was found significant (P cows. The statistic model succeeded in explaining 83.5% of the variance between Afi-CF and cows, and no significant variance was found between the mean weekly repeated recordings. Days in milk and log somatic cell count (SCC) had no significant effect. Fat, protein and lactose significantly affected Afi-CF and the empirical van Slyke equation. Real-time simulations were performed for different cutoff levels of coagulation properties where the milk of high Afi-CF cutoff value was channeled to tank A and the lower into tank B. The simulations showed that milk coagulation properties of an individual cow are not uniform, as most cows contributed milk to both tanks. Proportions of the individual cow's milk in each tank depended on the selected Afi-CF cutoff. The assessment of the major causative factors of a cow producing low-quality milk for cheese production was evaluated for the group that produced the low 10% quality milk. The largest number of cows in those groups at the three farms was found to be cows with post-intramammary infection with Escherichia coli and subclinical infections with streptococci or coagulase-negative staphylococci (∼30%), although the SCC of these cows was not significantly different. Early time in lactation together with high

  16. Special Milk Program

    Science.gov (United States)

    US Department of Agriculture, 2009

    2009-01-01

    The Special Milk Program provides milk to children in schools, child care institutions and eligible camps that do not participate in other Federal child nutrition meal service programs. The program reimburses schools and institutions for the milk they serve. In 2008, 4,676 schools and residential child care institutions participated, along with…

  17. Milk Allergy in Infants

    Science.gov (United States)

    ... Habits for TV, Video Games, and the Internet Milk Allergy in Infants KidsHealth > For Parents > Milk Allergy ... español Alergia a la leche en bebés About Milk Allergy People of any age can have a ...

  18. Physiochemical properties, microstructure, and probiotic survivability of nonfat goats' milk yogurt using heat-treated whey protein concentrate as fat replacer.

    Science.gov (United States)

    Zhang, Tiehua; McCarthy, James; Wang, Guorong; Liu, Yanyan; Guo, Mingruo

    2015-04-01

    There is a market demand for nonfat fermented goats' milk products. A nonfat goats' milk yogurt containing probiotics (Lactobacillus acidophilus, and Bifidobacterium spp.) was developed using heat-treated whey protein concentrate (HWPC) as a fat replacer and pectin as a thickening agent. Yogurts containing untreated whey protein concentrate (WPC) and pectin, and the one with only pectin were also prepared. Skim cows' milk yogurt with pectin was also made as a control. The yogurts were analyzed for chemical composition, water holding capacity (syneresis), microstructure, changes in pH and viscosity, mold, yeast and coliform counts, and probiotic survivability during storage at 4 °C for 10 wk. The results showed that the nonfat goats' milk yogurt made with 1.2% HWPC (WPC solution heated at 85 °C for 30 min at pH 8.5) and 0.35% pectin had significantly higher viscosity (P yogurts and lower syneresis than the goats' yogurt with only pectin (P yogurt samples did not change much throughout storage. Bifidobacterium spp. remained stable and was above 10(6) CFU g(-1) during the 10-wk storage. However, the population of Lactobacillus acidophilus dropped to below 10(6) CFU g(-1) after 2 wk of storage. Microstructure analysis of the nonfat goats' milk yogurt by scanning electron microscopy revealed that HWPC interacted with casein micelles to form a relatively compact network in the yogurt gel. The results indicated that HWPC could be used as a fat replacer for improving the consistency of nonfat goats' milk yogurt and other similar products.

  19. 牛乳乳清蛋白的主要组成及其营养特点%A Review on Major Components and Nutritional Properties of Cow Milk Whey Protein

    Institute of Scientific and Technical Information of China (English)

    庞孝飞; 汪超

    2016-01-01

    乳清蛋白是牛乳中的一类重要蛋白质,主要由α-乳白蛋白、乳铁蛋白、血清白蛋白、β-乳球蛋白、免疫球蛋白及乳过氧化物酶等构成,对人体健康有重要作用。介绍了牛乳乳清蛋白的主要组成及其营养特点,分析了影响牛乳乳清蛋白产品开发的关键因素,以期为进一步研究牛乳乳清蛋白在不同处理条件下的营养变化特征以及牛乳乳清蛋白相关产品的开发利用提供理论依据。%Whey protein, which is mainly composed of α -lactalbumin, lactoferrin, serum albumin, β -lactoglobulin, immunoglobulin and lactoperoxidase, plays an important role in human health. Here, we introduced the major components and nutritional properties of cow milk whey protein and analyzed the key factors associated with the development of commercial cow milk whey protein products, so as to provide theoretical basis for the further study on changing features of nutrition components of cow milk whey protein under different treatment condition and for the development and application of commercial cow milk whey protein products.

  20. Pharmaceuticals and Dietary Supplements Extracted from Mare’s Milk

    Directory of Open Access Journals (Sweden)

    Anca Alexandra Stuparu

    2016-01-01

    Full Text Available Mare’s milk is similar to human breast milk and has valuable therapeutic properties. For this reason, Europeans are increasingly interested in discovering its benefits and how the chemical composition of horse milk differs from that of other species. This interest is reflected in the number of new farms selling mare’s milk around the world as this milk is the most similar to human milk. Mare’s milk is considered to be highly digestible, rich in essential nutrients and whey protein, which makes it very suitable as a substitute for bovine milk in paediatric diets. During the period of lactation, mammal's milk composition is subject to rapid changes in macro- and micro-elements, as well as in the quantity and quality of proteins, lipids and saccharides, being ideal food for infants. The primary use of mare’s milk has been the rearing of foals, but recently, due to the similarity of its chemical composition to that of human milk, it has raised particular interest and some experiments have been done to apply it as a raw material for the preparation of special food products for human consumption. Mare’s milk products are very common in Russia and Central Asia throughout Mongolia. In the 19th century, some Russian scientists explored its therapeutic properties and then in 1859 they founded the first sanatorium where treatments with mare’s milk could be made under medical control. Due to its potential health-promoting characteristics, in the Western countries, interest in mare's milk has lately increased.

  1. Prediction of individual milk proteins including free amino acids in bovine milk using mid-infrared spectroscopy and their correlations with milk processing characteristics.

    Science.gov (United States)

    McDermott, A; Visentin, G; De Marchi, M; Berry, D P; Fenelon, M A; O'Connor, P M; Kenny, O A; McParland, S

    2016-04-01

    -infrared spectroscopy predictions (0.95). Weaker correlations among FAA were observed than the correlations among the protein fractions. Pearson correlations between gold standard protein fractions and the milk processing characteristics of rennet coagulation time, curd firming time, curd firmness, heat coagulating time, pH, and casein micelle size were weak to moderate and ranged from -0.48 (protein and pH) to 0.50 (total casein and a30). Pearson correlations between gold standard FAA and these milk processing characteristics were also weak to moderate and ranged from -0.60 (Val and pH) to 0.49 (Val and K20). Results from this study indicate that mid-infrared spectroscopy has the potential to predict protein fractions and some FAA in milk at a population level. Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  2. Differences of protein fractions among fresh, frozen and powdered donkey milk.

    Science.gov (United States)

    Polidori, Paolo; Vincenzetti, Silvia

    2010-01-01

    Recently donkey milk has been the focus of several studies because of its special nutritional properties and composition, which is very close to human milk. When a mother cannot breastfeed, or chooses not to breastfeed, the use of a milk substitute must provide the best option to meet the nutritional and health needs of the infant. Donkey milk has been widely used in the past to replace human milk, because chemical composition and protein content are close to that of human milk, and also because the allergenicity of donkey milk is low. The recent studies of the paediatric scientists have demonstrated that infant formulae, which are based on dairy cows milk, are less adapted than donkey milk. In fact, donkey's milk digestibility is higher than cows' milk and similar to human milk, because of the high whey proteins content and the few casein content. Since donkey milk supply is related to its seasonal availability during the year, in this study were evaluated the effects of a specific technological treatment (spray-dryer) and a particular storage temperature (-20 degrees C) on the protein fractions of donkey milk. The results obtained in fresh, frozen and powdered donkey milk showed different values in total proteins, caseins, whey proteins and lysozyme content. The article presents some promising patents on protein fractions among fresh, frozen and powdered donkey milk.

  3. Phenotypic analysis of cheese yields and nutrient recoveries in the curd of buffalo milk, as measured with an individual model cheese-manufacturing process.

    Science.gov (United States)

    Cipolat-Gotet, C; Bittante, G; Cecchinato, A

    2015-01-01

    Traits associated with cheese yield and milk nutrient recovery in curd are used to describe the efficiency of the cheese-making process. This is fundamental for all dairy species, including the Italian Mediterranean buffalo, which is largely used for milk production aimed at the dairy industry. To assess cheese-making traits among buffalo, a model cheese-manufacturing process was tested; it was capable of processing 24 samples per run, using 0.5-L samples of milk from individual buffalo. In total, 180 buffalo reared in 7 herds located in Northeast Italy were sampled once. Briefly, each sample was weighed and heated (35°C for 30min), inoculated with starter culture (90min), and mixed with rennet (51.2 international milk-clotting units/L of milk). After 10min of gelation, the curd was cut; 5min after the cut, the curd was separated from the whey, and the curd was subjected to draining (for 30min) and pressing (18h). The curd and whey were weighed, analyzed for pH and the total solid, fat, lactose, and protein contents, and subjected to estimation of the energy content. Three measures of cheese yield (%CY), %CYCURD, %CYSOLIDS, and %CYWATER, were computed as the ratios between the weight of the curd, the curd dry matter, and the water retained in the curd, respectively, and the weight of the milk processed. These traits were multiplied by the daily milk yield to define the 3 corresponding measures of daily cheese yield (dCY, kg/d). The milk component recoveries (REC) in the curd, RECFAT, RECPROTEIN, and RECSOLIDS, represented the ratios between the weights of the fat, protein, and total solids in the curd, respectively, and the corresponding components in the milk. Finally, energy recovery (RECENERGY) was estimated. The values for %CYCURD, %CYSOLIDS, %CYWATER, RECPROTEIN, RECFAT, RECSOLIDS, and RECENERGY averaged 25.6, 12.7, 12.9, 80.4, 95.1, 66.7, and 79.3%, respectively, indicating that buffalo milk has a higher aptitude to cheese-making than bovine milk. The effect

  4. 21 CFR 133.165 - Parmesan and reggiano cheese.

    Science.gov (United States)

    2010-04-01

    ... the same physical and chemical properties as the cheese produced when the procedure set forth in... milk or added thereto. Sufficient rennet, or other safe and suitable milk-clotting enzyme that produces... larger than wheat kernels, heated, and stirred until the temperature reaches between 115 °F and 125...

  5. Low-fat Gouda cheese made from bovine milk-olive oil emulsion: physicochemical and sensory attributes.

    Science.gov (United States)

    Felfoul, Imène; Bornaz, Salwa; Baccouche, Aroua; Sahli, Ali; Attia, Hamadi

    2015-10-01

    The objective of this paper is to study the effect of milk-fat replacement on Gouda cheeses composition, lipolysis and sensory characteristics. A Gouda cheese-like product was prepared from the substitution of milk fat with emulsified olive oil. For comparison, the low-fat variant without fat replacers and the full-fat cheese were also studied. Milk samples are initially pasteurized at 72 °C for 3 s, cooled to 35 °C, and added with 0.016 g L(-1) of lactic ferments and 0.30 mL L(-1) of microbial rennet. Total solids content was lower in cheeses containing fat replacers than in full and low-fat control cheeses due to the higher water-binding capacity of fat replacers. Free fatty acids rates were the highest in the case of reduced fat cheese-like product. The full-fat cheese showed a significantly higher overall impression score than all low-fat products.

  6. Pea (Pisum sativum and faba beans (Vicia faba in dairy cow diet: effect on milk production and quality

    Directory of Open Access Journals (Sweden)

    Maurizio Moschini

    2012-04-01

    Full Text Available The use of alternative plant proteins in place of the soybean meal protein in diets for producing animals aims to reduce the extra-EU soybean import and partially substitute the GMO in the food chain. Among possible alternatives, the heat-processed legume grains seem interesting for dairy cow diets. Two consecutive experiments were carried out to evaluate flaked pea and faba beans as substitute for soybean meal in diets for Reggiana breed dairy cows producing milk for Parmigiano-Reggiano cheese-making. In both experiments a C concentrate (110 g/kg soybean meal, no pea and faba beans was compared to a PF concentrate (150 g/kg flaked pea, 100 g/kg flaked faba beans, no soybean meal. Forages fed to animals were hay (mixed grass and alfalfa in experiment 1 and hay plus mixed grass in experiment 2. Concentrate intake, milk yield and milk quality (rennet coagulation traits included were similar between feeding groups. Parameters on the grab faecal samples, as empirical indicators of digestibility, had a smaller (Pvs 3.1 and 2.3 vs 2.8%, respectively for PF and C in experiment 1 and 2. Some blood indicators of nitrogen metabolism (protein, albumin, urea were similar between the feeding groups. The inclusion of pea and faba beans, within the allowed limit of the Parmigiano-Reggiano Consortium for diet formulation, could represent a feasible opportunity for a total substitution of soybean meal.

  7. Comparative Analysis of the Physicochemical Parameters of Breast Milk, Starter Infant Formulas and Commercial Cow Milks in Serbia

    OpenAIRE

    Sunarić Slavica; Jovanović Tatjana; Spasić Ana; Denić Marko; Kocić Gordana

    2016-01-01

    Data on the physical properties of cow milk and infant formulas are important since they indicate the differences in physicochemical and rheological characteristics and compatibility with natural breast milk. This fact is important not only for quality control but also for the use of these commercial products as infant diet supplements or as complete breast milk substitutes. This study was undertaken to determine refractive index, surface tension, pH, electrical conductivity, viscosity and ti...

  8. Comparative analysis of the physicochemical parameters of breast milk, starter infant formulas and commercial cow milks in Serbia

    OpenAIRE

    Sunarić, Slavica; Jovanović, Tatjana; Spasić, Ana; Denić, Marko; Kocić, Gordana

    2016-01-01

    Data on the physical properties of cow milk and infant formulas are important since they indicate the differences in physicochemical and rheological characteristics and compatibility with natural breast milk. This fact is important not only for quality control but also for the use of these commercial products as infant diet supplements or as complete breast milk substitutes. This study was undertaken to determine refractive index, surface tension, pH, electrical conductivity, viscosity and ti...

  9. Spoilage microorganisms in milk and dairy products

    Directory of Open Access Journals (Sweden)

    Andrea Skelin

    2007-12-01

    Full Text Available Spoilage microorganisms cause changes of primary characteristics and properties of milk and dairy products. The product defects depends on the specific species and number of microorganisms involved in pre- and post- technological processing. Most often, these changes are related to single undesirable sensory characteristic, smell, flavour or conistency. However, in the case of heavier microbial contamination all these undesirable characteristics can occur simultaneously. Besides, even small changes caused by presence of spoilage microorganisms lead to decreased quality of milk and various dairy products. Despite of the importance for the overall quality, the control of spoilage microorganisms for dairy industry is not obligated and therefore, only a few producers control them. Therefore, the present study describes the undesirable effect of spoilage microorganisms on quality of raw, pasteurized and sterilized milk, fermented milk, butter, sour cream and cheeses with the intention to emphasize the importance and significance of their control in the dairy industry.

  10. 低浓度酸碱溶液对牛奶蛋白纤维拉伸性能的影响%Impacts of weak acid and alkali solution on the tensile properties of milk protein fiber

    Institute of Scientific and Technical Information of China (English)

    何文元

    2012-01-01

    This paper studies the effect of weak acid and alkali solution on the tensile properties of milk protein fiber by orthogonal experimental method. The variance analysis of experimental data show that pH, temperature and time of processing have no significant impacts on breaking elongation rate, breaking strength, initial tensile modulus and other performance indicators of milk protein fiber in solution of weak acid and alkali when the significance level a is 10 %, and temperature is lower than 90 ℃, and time of processing is shorter than 120 mins. The comparison between experimental data before and after the processing of the milk protein fiber also show that weak acid and alkali solution will not evidently damage the milk protein fiber. And the milk protein fiber and its product can be dyed and finished, post-processed and maintained in weak acid and alkali solution whose pH value is 4~9.%通过正交试验的方法,研究了低浓度酸碱溶液对牛奶蛋白纤维拉伸性能的影响.试验数据方差分析显示,显著性水平a为10%时,在低浓度酸碱溶液中,溶液的温度低于90℃,处理时间小于120 min的条件下,pH值、温度和处理时间对牛奶蛋白纤维的断裂伸长率、断裂强度和初始模量等拉伸性能指标没有显著影响.牛奶蛋白纤维处理前后的试验数据对比也说明了低浓度酸碱溶液不会对牛奶蛋白纤维造成显著的损伤.研究表明,牛奶蛋白纤维及其产品应该在pH值为4~9的低浓度酸碱溶液中进行染整、后处理及维护保养.

  11. Short communication: The effect of raw milk cooling on sensory perception and shelf life of high-temperature, short-time (HTST)-pasteurized skim milk.

    Science.gov (United States)

    Lee, A P; Barbano, D M; Drake, M A

    2016-12-01

    The cooling rate of raw milk may influence sensory properties and pasteurized shelf life. Under the Pasteurized Milk Ordinance for grade A milk, raw milk may be cooled instantaneously by on-farm heat exchangers but is also acceptable if "cooled to 10°C or less within four (4) hours of the commencement of the first milking." The objective of this study was to determine the effect of raw milk cooling on consumer perception and shelf life. Raw milk (18-21°C) was obtained and transported within 1h of milking to North Carolina State University (Raleigh). The batch of raw milk was split in 2 portions, and a plate heat exchanger was used to quickly cool one portion to shelf life. The entire experiment was repeated in triplicate. Raw milks averaged 3.3 logcfu/mL by aerobic plate count, shelf life. These results suggest that pasteurized milk quality is due to a combination of many factors. Raw milk cooling rate is not the most important factor affecting milk quality when raw milk quality is excellent. Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  12. Research of rheologic properties of coix seed yoghurt using recombined milk and optimization of processing%薏苡仁酸奶的流变性及工艺条件的优化研究

    Institute of Scientific and Technical Information of China (English)

    朱旭君; 黄杰; 王妍; 顾欣辰; 刘少伟

    2011-01-01

    The rheologic properties of coix seed yoghurt had been studied using reconstituted milk.The result indicated that viscosity increased while sensory properties deteriorated(including taste,color,flavor and so on)and water holding power reduced compared with using fresh milk.The quality of yoghurt could be improved through high-pressure homogenization,the best pressure was 20MPa,at the same time when additive amount of white sugar and extract of coix seed were 6% ~ 8% and 4%,respectively,the best quality of coix seed yoghurt was obtained.%实验用复原乳制备薏苡仁酸奶,研究其流变学性质。结果显示,与生鲜乳相比,复原乳酸奶粘度显著提高,但感官性质(口感、色泽、滋味等)下降,持水力也降低。通过均质处理可以提高酸奶的品质,最佳均质压力为20MPa,且当白砂糖的添加量为6%~8%,薏苡仁提取液添加量为4%时,薏苡仁酸奶品质最佳。

  13. Protein composition of rhesus monkey milk: comparison to human milk.

    Science.gov (United States)

    Kunz, C; Lönnerdal, B

    1993-04-01

    1. Proteins in human milk and Rhesus monkey milk have been compared by FPLC gel filtration and anion exchange chromatography, SDS-Polyacrylamide gel electrophoresis, nitrogen and protein determination. 2. Mature Rhesus milk is higher in protein concentration (15-20 mg/ml) than human milk (8-9 mg/ml). 3. Non-Protein nitrogen is 6-13% in Rhesus milk but 25-30% in human milk. 4. Secretory IgA, lactoferrin, serum albumin, alpha-lactalbumin and lysozyme are present in Rhesus milk, but at a lower concentration than in human milk. 5. The casein subunit pattern is more complex in Rhesus milk compared to human milk. 6. The ratio of whey proteins to casein is similar in both milks (approximately 60/40). 7. A protein with a M(r) of 21,600 is a major component in monkey whey but is not found in human milk.

  14. Cow's milk proteins in human milk.

    Science.gov (United States)

    Coscia, A; Orrù, S; Di Nicola, P; Giuliani, F; Rovelli, I; Peila, C; Martano, C; Chiale, F; Bertino, E

    2012-01-01

    Cow's milk proteins (CMPs) are among the best characterized food allergens. Cow's milk contains more than twenty five different proteins, but only whey proteins alpha-lactalbumin, beta-lactoglobulin, bovine serum albumin (BSA), and lactoferrin, as well as the four caseins, have been identified as allergens. Aim of this study was to investigate by proteomics techniques cow's milk allergens in human colostrum of term and preterm newborns' mothers, not previously detected, in order to understand if such allergens could be cause of sensitization during lactation. Term colostrum samples from 62 healthy mothers and preterm colostrum samples from 11 healthy mothers were collected for this purpose. The most relevant finding was the detection of the intact bovine alpha-S1-casein in both term and preterm colostrum. Using this method, which allows direct proteins identification, beta-lactoglobulin was not detected in any of colostrum samples. According to our results bovine alpha 1 casein that is considered a major cow's milk allergen is readily secreted in human milk: further investigations are needed in order to clarify if alpha-1-casein has a major role in sensitization or tolerance to cow's milk of exclusively breastfed predisposed infants.

  15. The effect of digestive enzymes on the binding and bacteriostatic properties of lactoferrin and vitamin B12 binder in human milk.

    Science.gov (United States)

    Samson, R R; Mirtle, C; McClelland, D B

    1980-07-01

    Human milk contains unsaturated lactoferrin and vitamin B12 binding protein. It has been suggested that these proteins may exert antibacterial effects in the intestine of the breast fed infant, but the effect of the intestinal environment on the antibacterial effect of these proteins has not been described. In this study human milk was treated with pepsin and trypsin and the influence of digestion on iron and vitamin B12 binding capacity, bacterial uptake of iron and vitamin B12 from milk and bacteriostatic effect was studied. Pepsin digestion had no effect on vitamin B12 binding capacity, or the ability of bacteria to take up vitamin B12, or the growth inhibitory effect on a vitamin B12 dependent strain. In contrast, trypsin digestion did not affect iron binding or bacteriostatic effects attributable to lactoferrin. The. findings support an in vivo bacteriostatic role for lactoferrin in the breast fed neonate's intestine but do not support a similar role for the vitamin B12 binding protein.

  16. Effect of milk fat, cocoa butter, and whey protein fat replacers on the sensory properties of lowfat and nonfat chocolate ice cream.

    Science.gov (United States)

    Prindiville, E A; Marshall, R T; Heymann, H

    2000-10-01

    Lowfat and nonfat chocolate ice creams were made with 2.5% of milk fat, cocoa butter, or one of two whey protein-based fat replacers, Dairy Lo or Simplesse. Polydextrose was added as required so that all formulations contained the same amount of total solids. Ice cream was stored at a control temperature of-30 degrees C. Hardness, viscosity, and melting rate were measured by physical methods. Trained panelists conducted descriptive sensory analyses of the samples at 0, 6, and 12 wk. Attribute ratings were analyzed by analysis o variance with least significant difference mean separation and orthogonal contrasting. Data were also analyzed by multivariate analysis of variance with canonical variate analysis. Consumer acceptance (n = 50) did not differ among the fresh ice creams (wk 0). Ice cream containing milk fat had less intense cocoa flavor and was more resistant to textural changes over time compared with the other ice creams. Simplesse was more similar to milk fat than was Dairy Lo in its effect on brown color, cocoa flavor, cocoa character, and textural stability but was less similar in terms of thickness and mouthcoating.

  17. Comparison of Chamcham manufactured from cow milk and buffalo milk

    OpenAIRE

    Haque, M A; Rashid, M H; Kajal, M.F.I.; Istiak, M.S.

    2012-01-01

    This experiment was conducted to study quality of Chamcham manufactured from cow milk and to compare it with Chamcham manufactured from buffalo milk and mixture of cow and buffalo milk. Three types of Chamcham were prepared from cow milk(A), buffalo milk(B) and 50% cow +50% buffalo milk(C).In this experiment the quality of prepared Chamcham were evaluated with the help of chemical test. The moisture, total solids, protein, fat, ash and carbohydrate contents of cow milk and buffalo milk Chamch...

  18. Detection of electrical properties of soybean milk based on AC impedance method%基于交流阻抗法的豆浆电特性检测

    Institute of Scientific and Technical Information of China (English)

    宋华鲁; 闫银发; 宋占华; 陈晨; 李法德

    2015-01-01

    In order to rapidly detect soybean milk quality and to optimize the frequency of power for ohmic heating device, the electrical impedance characteristics of soybean milk with different solid contents (ranging from 1.01%to 9.58%) at different temperatures (ranging from 30 °C to 85 °C with 5 °C interval) were measured with an impedance analyzer at a frequency ranging from 20 Hz to 12 MHz. The impedance analyzer equipped with a commercial conductivity electrode (DJS-10) was operated at a measurement voltage of 50 mV. The temperature of the soybean milk contained in a jacket beaker was controlled with water flowing through the jacket at a constant temperature. The results showed that the impedance amplitude of the soybean milk decreased with the increase in frequency at a low frequency (f300 kHz). The impedance phase angle decreased with the increase in frequency at the low frequency range, and it tended to be zero in the middle-frequency range, while it showed the trend of increase in the high frequencies range. The results showed that the electrical impedance of soybean milk was significantly influenced by the temperature and solid content of soybean milk. There were clear distinctions among the Nyquist plot of electrical impedance for soybean milk with different solid contents at different temperatures. The electrical impedance amplitude of the soybean milk decreased with the increase in temperature and solid content in full frequency range. The impedance phase angle of the soybean milk increased with the increase in temperature and solid content in the low frequency range, while it showed the trend of decrease in the high frequency range. An equivalent electrical circuit of soybean milk which consisted of a resistor a capacitor and a constant phase element (CPE) was built for simulating the impedance data acquired during experiments. The electrical parameters of the equivalent electrical circuit were acquired with the ZSimpWin software. By analyzing the change

  19. Food Safety and Raw Milk

    Science.gov (United States)

    ... and Food Safety Food Safety Modernization Act Raw Milk Recommend on Facebook Tweet Share Compartir RAW MILK ... Decide? Questions & Answers Outbreak Studies Resources & Publications Raw Milk Infographic [PDF – 1 page] More Resources 5 Raw ...

  20. Milk: Past and Present

    Science.gov (United States)

    Bulajić, S.; Đorđević, J.; Ledina, T.; Šarčević, D.; Baltić, M. Ž.

    2017-09-01

    Although milk/dairy consumption is part of many cultures and is recommended in most dietary guidelines around the world, its contribution to overall diet quality remains a matter of controversy, leading to a highly polarized debate within the scientific community, media and public sector. The present article, at first, describes the evolutionary roots of milk consumption, then reviews the milk-derived bioactive peptides as health-promoting components. The third part of the article, in general, presents the associations between milk nutrients, disease prevention, and health promotion.

  1. Sphingosine basis in milk

    Directory of Open Access Journals (Sweden)

    Slavica Ribar

    2006-12-01

    Full Text Available Sphingolipids are widespread membrane components that are found in all eukaryotic cells. They are defined as compounds having a long-chain sphingoid base as the backbone. The most frequent long-chain bases in most of the mammals are D-erythro-sphinganine and sphingosine. Sphingolipids can be expected in minor quantities in all food products. Milk fat contains a number of different sphingolipid classes. Originally they were presumed to contribute to the structural integrity of membranes, but there nowadays it is confirmed that they have an important physiological role. Dietary sphingolipids have gained attention because of their possibility to inhibit colon cancer. The aim of this study was to determine the concentrations of free and total sphinganine and sphingosine in milk (human, cow's, sheep’s, goat’s, soy’s Sphingolipids were extracted from milk. Free and total sphingoid bases were obtained by alkaline and acid hydrolysis respectively. Sphinganin and sphingosine were determined by means of high-performance liquid chromatography. The results of this research illustrate the differences between the concentrations of sphingoid bases in cow’s milk with various content of milk fat. The concentrations of free sphingosine and sphinganine in cow’s milk were lower than in human milk. In sheep’s and goat’s milk, the concentrations of total sphingoid bases were higher than in human and cow’s milk. Quantity of the most sphingoid bases decreased during pasteurization.

  2. Humanizing infant milk formula to decrease postnatal HIV transmission.

    Science.gov (United States)

    Blais, David R; Altosaar, Illimar

    2007-09-01

    There are currently no safe methods for feeding babies born from the 16 million HIV-infected women living in resource-constrained countries. Breast milk can transmit HIV, and formula feeding can lead to gastrointestinal illnesses owing to unsanitary conditions and the composition of milk formulations. There is therefore a need to ensure that breast milk substitutes provide optimal health outcomes. Given that the immune properties of several breast milk proteins are known, transgenic food crops could facilitate inexpensive and safe reconstitution of the beneficial breast milk proteome in infant formulae, while keeping the HIV virus at bay. At least seven breast milk immune proteins have already been produced in food crops, and dozens more proteins could potentially be produced if fortified formula proves effective in nursing newborns born to HIV-infected mothers.

  3. Simulation and Flexibility Analysis of Milk Production Process

    DEFF Research Database (Denmark)

    Cheng, Hongyuan; Friis, Alan

    . In this work, a simulator is obtained for the milk production line. Using the simulator, different milk processing situation can be quantitatively simulated investigated, such as different products production, capacity changes, fat content changes in raw milk, energy cost at different operation conditions etc...... processing conditions are investigated through the simulator. A flexible operation range or ‘operation window’ is obtained from the simulation for the milk production line. The study gives both the operation feasibility and detailed operation cost.......In this work, process simulation method is used to simulate pasteurised market milk production line. A commercial process simulation tool - Pro/II from Simulation Science Inc. is used in the simulation work. In the simulation, a new model is used to calculate the thermal property of milk...

  4. Relationships between milk protein composition, milk protein variants, and cow fertility traits in Dutch Holstein-Friesian cattle

    NARCIS (Netherlands)

    Demeter, R.M.; Markiewicz, K.; Arendonk, van J.A.M.; Bovenhuis, H.

    2010-01-01

    Selective breeding can change milk protein composition to improve the manufacturing properties of milk. However, the effects of such breeding strategies on other economically important traits should be investigated before implementation. The objectives of this study were to examine the association b

  5. Fermented milk by single/multiple lactic strains isolated from "Viili"-the fermentation process, texture properties and sensory evaluation%Viili源乳酸菌酸奶发酵工艺及质构/感官性质评价

    Institute of Scientific and Technical Information of China (English)

    陈丽丽; 冯秀娟; 左芳雷; 陈尚武

    2013-01-01

    The aim of the study is to evaluate the fermented milk fermented by single Lactococcus.lactis subsp.lactis strain isolated from "Viili" and by the composite microbial system of "Viili".By optimizing temperature and the composition of culture media,we found that the most effective culture medium is GM17 plus 10 g/L reconstituted skimmed milk (RSM),and the fermentation tempurature is 28 ℃.Based on the texture properties and sensory evaluation,We made two different fermented milk via the adjustment of the proportion of the strains.We also investigated the survival rates of Lactococcus.lactis subsp.lactis and composite microbial system of "Viili" in the presence of different cryoprotectants,coming to a conclusion that the best protection was achieved with 100 g/L RSM plus 100 g/L trehalose.%采用分离自Viili发酵乳的乳酸乳球菌乳脂亚种和Viili天然复合菌系的混合菌种制作发酵乳.通过优化温度和培养基、评价发酵乳的质构性质和感官性质和分析冷冻干燥后菌株的存活率,确定菌种活化的最适培养基为GM17+质量浓度10 g/L脱脂乳,最适发酵温度为28℃;调整菌种的复配比例,得到两种不同质构和感官性质的发酵乳产品;冷冻干燥的最佳保护剂组合为100 g/L脱脂乳+100g/L海藻糖.

  6. Survey on the fatty acids profile of fluid goat milk

    Directory of Open Access Journals (Sweden)

    Daniela Pittau

    2013-10-01

    Full Text Available Fluid goat milk submitted to thermal treatment has interesting nutritional properties and a potential expanding market. The present study was aimed to conduct fatty acids profile characterisation of goat milk placed on market. Forty-nine fluid milk samples were collected: 12 pasteurised, 12 pasteurised at high temperature, 11 ultrahigh temperature (UHT whole milk and 14 UHT semi-skimmed milk. Milk samples were collected at retail level from 7 different companies and from different production batches. After extraction and methilation, fatty acids (FAs profile was determined on each sample using a gas chromatograph with flame ionisation detector (GC-FID with high-polarity capillary column. The concentration (g/100mL of saturated fatty acids (SFAs, monounsaturated fatty acids (MUFAs, polyunsaturated fatty acids (PUFAs, trans fatty acids (t-FAs, and isomers of conjugated linoleic acid (CLA was determined. N-6/n-3 ratio, atherogenic index (AI and thrombogenic index (TI were also assessed. Fluid goat milk lipid profile was characterised by SFAs (68.4% of total FAs, PUFAs (5.3%, MUFAs (21.3%, t-FAs (3.6% and CLA (0.8%. The most represented fatty acids were: 16:0 (24.5%, 9cis-18:1 (18.2%, 18:0 (9.6%, 14:0 (9.5%, 10:0 (9.3% and 12:0 (4.5%. Nutritional indices were 2.8-6.8 for n-6/n-3 ratio; 2.3-2.9 for AI; and 2.7-3.2 for TI. Milk produced by small scale plants, with no milk fat standardisation, showed greater differences in fatty acid profile as compared to industrial plants milk. Large scale production is characterised by commingled bulk tank milk of different origins and then is more homogeneous. The whole goat milk supply chain should be controlled to obtain milk with fatty acids of high nutritional value.

  7. Transfer of terpenes from essential oils into cow milk.

    Science.gov (United States)

    Lejonklev, J; Løkke, M M; Larsen, M K; Mortensen, G; Petersen, M A; Weisbjerg, M R

    2013-07-01

    The objective of this study was to investigate the transfer of volatile terpenes from caraway seed and oregano plant essential oils into cow's milk through respiratory and gastrointestinal exposure. Essential oils have potential applications as feed additives because of their antimicrobial properties, but very little work exists on the transfer of their volatile compounds into milk. Lactating Danish Holstein cows with duodenum cannula were used. Gastrointestinal exposure was facilitated by infusing the essential oils, mixed with deodorized sesame oil, into the duodenum cannula. Two levels were tested for each essential oil. Respiratory exposure was facilitated by placing the animal in a chamber together with a sponge soaked in the essential oils. All exposures were spread over 9h. Milk samples were collected immediately before and after exposure, as well as the next morning. Twelve monoterpenes and 2 sesquiterpenes were analyzed in essential oils and in milk samples using dynamic headspace sampling and gas chromatography-mass spectrometry. In the essential oils, almost all of the terpenes were detected in both essential oils at various levels. For caraway, the monoterpenes limonene, carvone, and carvacrol were most abundant; in oregano, the monoterpenes carvacrol and ρ-cymene were most abundant. For almost all treatments, an immediate effect was detected in milk, whereas little or no effect was detected in milk the following day. This suggests that the transfer into milk of these volatile terpenes is fast, and that the milk will not be influenced when treatment is discontinued. Principal component analysis was used to elucidate the effect of the treatments on the terpene profile of the milk. Terpene content for treatment milk samples was characterized by the same terpenes found in the treatment essential oil used for that animal, regardless of pathway of exposure. The terpenes appear to be transferred unaltered into the milk, regardless of the pathway of exposure

  8. Calcium Impact on Milk Gels Formation

    DEFF Research Database (Denmark)

    Koutina, Glykeria

    , a sudden solubilization of micellar calcium was observed at 50 oC and 60 oC, which revealed an interesting role of calcium during acidification at elevated temperatures. After enrichment of milk with calcium D-lactobionate, the added calcium was distributed between the micellar and serum milk phase at pH 6.......6-6.0, but at pH 5.7-5.4 the added calcium remained mainly in the serum milk phase. The importance of pH for the distribution of the added calcium between the micellar and serum milk phase may affect bioavailability from enriched products and the distribution should be taken into consideration when designing new......Calcium is one of the several elements that can be found in milk distributed between the micellar and the serum milk phase. Calcium is important from a nutritional point of view, but its contribution to the functional and structural properties of dairy products has only recently been...

  9. Milking hygiene: new issues and opportunities from automatic milking

    Directory of Open Access Journals (Sweden)

    Lotte Bach Larsen

    2010-01-01

    Full Text Available Automatic milking offers the opportunity of in-line measurements of milk components, check of milking and cleaning procedures,and surveillance through the management program. These advantages may directly benefit the milk quality.Diversion of abnormal milk at time of milking is critical to the milk quality. It is proposed to define abnormal milk as milkbeing visibly changed in homogeneity or colour from that of normal milk. Several enzymes and other milk componentsmay be involved in the formation of clots in the milk. Based on reported changes in primarily the milk protein fraction asa response to infection of the mammary gland, different explanations for the generation of precipitates in mastitis milkare discussed. Automatic milking systems (AMS should have sensors to monitor and divert abnormal milk. The managementsystem of AMS provides an excellent opportunity to introduce Hazard Analyses Critical Control Points (HACCPsystems for surveying the milk quality. HACCP-based proposals are given for avoiding contamination of the bulk milk withmilk from cows with clinical mastitis and for ensuring a low bulk milk bacterial count.

  10. Evaluation of false positive results in microbial inhibitor tests for screening antibiotics in goat milk

    OpenAIRE

    Romero Rueda, Tamara

    2015-01-01

    Goat milk is primarily destined for the production of fermented products, in particular cheese. Therefore, the control of antibiotic residues in milk is of great importance, since these could have negative repercussions on technological properties of the milk as well as on the health of consumers. In milk quality control programs, microbial inhibitor tests are widely applied to detect antibiotics during the screening stage. However, tests are non-specific and may be affected...

  11. Updating Nutritional Data and Evaluation of Technological Parameters of Italian Milk

    Directory of Open Access Journals (Sweden)

    Pamela Manzi

    2013-06-01

    Full Text Available Different technologically treated Italian milks (whole and semi-skimmed ultra-high temperature (UHT, pasteurized and microfiltered milk, collected from 2009 to 2012, were evaluated for nutritional and technological properties. No significant differences in calcium and sodium were detected (p > 0.05, while significant differences were observed concerning phosphorus content, between whole and semi-skimmed milk, and lactose content, between pasteurized and UHT milk (p 0.05 were detected for choline, a functional molecule, between whole (11.3–14.6 mg/100 g and semi-skimmed milk (11.1–14.7 mg/100 g, but there were significant differences (p < 0.05 in processing milk (UHT vs. pasteurized milk and UHT vs. microfiltered milk. Among the unsaponifiable compounds, only 13 cis retinol and trans retinol showed differences in technologically treated milk (pasteurized vs. UHT milk and microfiltered vs. UHT milk; p < 0.05. In this research, the greater was the “severity” of milk treatment, the higher was the percent ratio 13 cis/trans retinol (DRI, degree of retinol isomerization. The degree of antioxidant protection parameter (DAP, useful to estimate the potential oxidative stability of fat in foods, was significantly different between whole and semi-skimmed milk (p < 0.05. Finally, the evaluation of color measurement of whole milk showed a good correlation between beta carotene and b* (r = 0.854 and between lactulose and a* (r = 0.862.

  12. Fermented milk for hypertension

    DEFF Research Database (Denmark)

    Usinger, Lotte; Reimer, Christina; Ibsen, Hans

    2012-01-01

    Fermented milk has been suggested to have a blood pressure lowering effect through increased content of proteins and peptides produced during the bacterial fermentation. Hypertension is one of the major risk factors for cardiovascular disease world wide and new blood pressure reducing lifestyle...... interventions, such as fermented milk, would be of great importance....

  13. Milk Thistle (PDQ)

    Science.gov (United States)

    ... effective, and to slow the growth of cancer cells (see Question 3 and Question 6 ). Milk thistle is usually taken in capsules or tablets (see Question 5 ). Small studies of milk thistle have been done in acute lymphoblastic leukemia , prostate cancer , breast cancer , head and neck cancer , ...

  14. Human Milk Fortification.

    Science.gov (United States)

    Simmer, Karen

    2015-01-01

    Human milk is the feed of choice for preterm infants. However, human milk does not provide enough nutrition, especially protein, for preterm infants to achieve target growth rates similar to those in utero (15-20 g/kg per day). Fortifiers for human milk, manufactured from bovine milk, are commercially available and routinely used for patients born milk fortifier that is manufactured from donor human milk is available in some developed countries and may confer some clinical benefits, including a reduction in necrotizing enterocolitis. Fortification can be added in a standardized protocol as per manufacturers' instructions. Human milk composition can be analyzed and fortification individualized to take into account the large variation from mother to mother. Alternatively, fortification can be increased in a stepwise manner based on assumed composition while monitoring blood urea levels for safety. The current aim is to prevent preterm infants dropping percentiles and falling below the 10th percentile at 36 weeks' corrected gestational age or discharge home. More data are required on how best to fortify human milk for preterm infants to achieve optimal growth, development and health outcomes in the long term. There is an urgent need for well-designed and informed randomized clinical trials in this vulnerable preterm population.

  15. Transglutaminase inhibitor from milk

    NARCIS (Netherlands)

    Jong, G.A.H. de; Wijngaards, G.; Koppelman, S.J.

    2003-01-01

    Cross-linking experiments of skimmed bovine milk with bacterial transglutaminase isolated from Streptoverticillium mobaraense showed only some degree of formation of high-molecular-weight casein polymers. Studies on the nature of this phenomenon revealed that bovine milk contains an inhibitor of tra

  16. Efeito da pressão de homogeneização nas propriedades funcionais do leite de soja em pó The effect of homogenization pressure on functional properties of powdered soybean milk

    Directory of Open Access Journals (Sweden)

    Lair C. CABRAL

    1997-12-01

    Full Text Available O leite de soja foi submetido a diferentes pressões (3.000; 4.000; 5.000 e 6.000 psi de homogeneização e em seguida, foi seco por atomização. As propriedades funcionais destes leites de soja em pó foram estudadas. Observou-se que houve melhoria na absorção de gordura, índice de dispersibilidade de proteína, índice de solubilidade de nitrogênio e nas propriedades emulsificantes com o aumento da pressão de homogeneização até 5.000 psi. Os valores numéricos para as propriedades espumantes não foram relevantes, embora as mesmas tenham sido também afetadas pelas diferentes pressões de homogeneização. Recomenda-se, portanto, o leite de soja em pó submetido previamente a homogeneização de 5.000 psi, para o uso em produtos de carne, bebidas, sopas, molhos, produtos de confeitaria e de chocolataria.The functional properties of powdered soybean milks submitted previously a homogenization pressures of 3,000; 4,000; 5,000 and 6,000 psi were studied. It was observed an improvement of fat absorption, protein dispersibility index, nitrogen solubility index and emulsification properties with the increase of homogenization pressure up to 5,000 psi. The value of foaming properties were not relevant, although they were affected by different homogenization pressures. The powdered soybean milk previously subjected to homogenization at 5,000 psi, can be therefore recommended for using in meat, chocolate and confectionary products, beverages, soups and sauces.

  17. Dietary supplementation with nonconventional feeds from the Middle East: assessing the effects on physicochemical and organoleptic properties of Awassi sheep milk and yogurt.

    Science.gov (United States)

    Hilali, M; Iñiguez, L; Knaus, W; Schreiner, M; Wurzinger, M; Mayer, H K

    2011-12-01

    Increased feed costs affect the livelihoods of dairy sheep farmers in the Middle East. Farmers endure high risks with large fluctuations in the price of grain used as animal feed, which is further affected by drought and declining range productivity. Using agricultural by-products and treated straw or vetch grazing for supplementing sheep diets would provide resource-poor dairy farmers with increased options to reduce feed costs, but the effects of such feeds on the quality of yogurt (the main product) need to be better understood. Two experiments were conducted to evaluate these effects. The first trial evaluated alternative diets using locally available feedstuffs, including agricultural by-products, compared with traditional diets used by dairy sheep farmers, and was conducted on-station at the International Center for Agricultural Research in Dry Areas (ICARDA, Tel Hadya, Aleppo, Syria). Milking Awassi ewes (n=56) were used to test 6 alternative diets against a traditional control diet containing barley, wheat bran, and barley straw. The 6 alternative diets contained 4 or more of the following ingredients: barley, sugar beet pulp, molasses, cotton seed cake, wheat bran, urea-treated wheat straw, and barley straw. Ewes on one of the alternative diets grazed vetch pasture, whereas ewes on the control diet and the 5 alternative diets grazed native range pasture. The milk fat content was higher in diets containing urea-treated straw. Yogurt firmness and adhesiveness were significantly lower in energy-rich diets (e.g., the control diet) and in the diets rich in soluble sugar (molasses). The effects of diet on yogurt color and on citric and succinic acid contents were significant. A yogurt produced from the milk of the group grazing on vetch was the most yellowish in color, which is appealing to Syrian consumers. The content of citric acid tended to be higher in yogurts produced from diets containing molasses. The second trial was conducted on 3 farms in northern

  18. Metoclopramide and breast milk.

    Science.gov (United States)

    de Gezelle, H; Ooghe, W; Thiery, M; Dhont, M

    1983-04-01

    Thirteen primiparous nursing mothers participated in this placebo-controlled double blind trial of metoclopramide. Therapy was started on the first postpartum day and continued for 8 days. Seven women received metoclopramide (10 mg, 3 X dd). Serum prolactin and milk yield were measured during the trial. The breast milk composition was analysed during the trial and weekly for 3 wk after the trial. A detailed analysis of the amino acid content was performed on the 6th and 21st postpartum days. During the early puerperium the total milk yield was ca. 50% greater in the metoclopramide-treated group compared to the control group. The evolution of the breast milk composition was similar for both groups, except for the amino acid content. The shift in amino acid composition occurred earlier in the treatment group indicating that metoclopramide enhances the rate of transition from colostrum to mature milk.

  19. Cow's Milk Allergy

    DEFF Research Database (Denmark)

    Høst, Arne; Halken, Susanne

    2014-01-01

    Since the 1930's the scientific literature on cow's milk protein allergy (CMPA) has accumulated. Over the last decade new diagnostic tools and treatment approaches have been developed. The diagnosis of reproducible adverse reactions to cow's milk proteins (CMP), i.e. CMPA, still has to be confirmed...... by controlled elimination and challenge procedures. Advanced diagnostic testing using epitope and microarray technology may in the future improve the diagnostic accuracy of CMPA by determination of specific IgE against specific allergen components of cow's milk protein. The incidence of CMPA in early childhood...... is approximately 2-3% in developed countries. Symptoms suggestive of CMPA may be encountered in 5-15% of infants emphasizing the importance of controlled elimination/milk challenge procedures. Reproducible clinical reactions to CMP in human milk have been reported in 0.5% of breastfed infants. Most infants...

  20. Milk Production in Croatia

    Directory of Open Access Journals (Sweden)

    Petar Bosnić

    2003-09-01

    Full Text Available In the last few years Croatian economy is restructuring through the processes of market liberalization and closing to EU, which is demanding some significant changes. Agriculture is in the process of reforms on the basis of CAP (Common Agricultural Policy policies of the EU, and those changes are producing different effects in each agricultural sector. The most sensitive area is livestock production, especially cattle and milking cows (production of meat and milk. This sector has insufficient production. More precise, domestic production in Croatia can satisfy around 80% of one-year consumption. This study shows economic position of production and processing of milk with the emphasis on primary milk production, processing of milk, domestic market and export-import situation. The goal is to consider the situation, position and possibilities for development of this sector.

  1. 9 CFR 94.16 - Milk and milk products.

    Science.gov (United States)

    2010-01-01

    ... products, including dry whole milk, nonfat dry milk, dried whey, dried buttermilk, and formulations which... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Milk and milk products. 94.16 Section... VESICULAR DISEASE, AND BOVINE SPONGIFORM ENCEPHALOPATHY: PROHIBITED AND RESTRICTED IMPORTATIONS § 94.16...

  2. The predominance, biodiversity and biotechnological properties of Kluyveromyces marxianus in the production of Pecorino di Farindola cheese.

    Science.gov (United States)

    Tofalo, Rosanna; Fasoli, Giuseppe; Schirone, Maria; Perpetuini, Giorgia; Pepe, Alessia; Corsetti, Aldo; Suzzi, Giovanna

    2014-09-18

    Pecorino di Farindola is a handicraft cheese made by farmers on small scale using raw ewes' milk and pig rennet. In this study, yeast consortia were evaluated during Pecorino di Farindola making and ripening. Molecular identification of 156 isolates was achieved by a combination of PCR-RFLP of the 5.8S ITS rRNA region and sequencing of the D1/D2 domain of the 26S rRNA gene. Kluyveromyces marxianus was the predominant species, while other species (Pichia kudriavzevii, Candida parapsilosis, Candida glaebosa and Candida zeylanoides) were present only during the early weeks of ripening. Moreover, the isolates were differentiated both by RAPD-PCR and a sequence alignment of D1/D2 26S rRNA gene, revealing different K. marxianus profiles and variants, and suggesting the role of local selective pressure as the origin of distinctive K. marxianus populations. The strains were characterized also on the basis of different dairy properties such as growth temperature, lactose, galactose, lactate and citrate assimilation at different NaCl concentrations, as well as lipolytic and caseinolytic activities. Moreover, 39 selected K. marxianus strains were inoculated in pasteurized whey to evaluate their growth kinetics, besides lactose, lactate and free amino acids metabolism. The growth kinetics distinguished different biotypes and different metabolic behavior were determined. The general picture of K. marxianus population from Pecorino di Farindola shows a high biodiversity at genetic and phenotypic levels that potentially offers many opportunities for new and advanced knowledge at species level, providing in the meantime a good basis to study the relationship between genetic variability and functional diversities.

  3. Camels Milk: Nutrition and Health Perspectives Iranian Traditional Medicine

    Directory of Open Access Journals (Sweden)

    Seyyd Musa al-Reza Hosseini

    2015-09-01

    Full Text Available Background: Camel milk is the closest to human mother’s milk. In the references on Iranian traditional medicine, camel’s milk has been represented as the one having numerous nutritious and medical properties.Objectives: In this article, the nutritive and therapeutic effects of camel’s milk have been examined from the view point of Iranian traditional medicine.Materials and Methods: The present study is a qualitative one, which was carried out, based on certain criteria, through purposeful search of certain keywords in the written references of Iranian traditional medicine.Results: Numerous pharmacological functions and therapeutic effects of camel’s milk on patients suffering from liver, kidney, bladder, spleen, stomach and intestines, uterus, skin, lungs, and brain diseases have been mentioned. Camel’s milk seems to be an appropriate alternative/supplement to nourish infants and children.Conclusions: Animal resources, such as camel’s milk and its various products, have comprehensively been dealt with regarding their nutritive and therapeutic effects. Its compatibility with and similarity to mother’s milk have led to its application in pediatrics; thus, offering valid information to pediatricians on camel’s milk can further enhance the consumption of this natural product.

  4. Rheology and structure of milk protein gels

    NARCIS (Netherlands)

    Vliet, van T.; Lakemond, C.M.M.; Visschers, R.W.

    2004-01-01

    Recent studies on gel formation and rheology of milk gels are reviewed. A distinction is made between gels formed by aggregated casein, gels of `pure` whey proteins and gels in which both casein and whey proteins contribute to their properties. For casein' whey protein mixtures, it has been shown th

  5. Rheology and structure of milk protein gels

    NARCIS (Netherlands)

    Vliet, van T.; Lakemond, C.M.M.; Visschers, R.W.

    2004-01-01

    Recent studies on gel formation and rheology of milk gels are reviewed. A distinction is made between gels formed by aggregated casein, gels of `pure` whey proteins and gels in which both casein and whey proteins contribute to their properties. For casein' whey protein mixtures, it has been shown

  6. Use of milk-based kombucha inoculum for milk fermentation

    OpenAIRE

    Kolarov Ljiljana A.; Milanović Spasenija D.; Lončar Eva S.; Malbaša Radomir V.

    2009-01-01

    In this investigation fermented milk beverages with 0.9% of milk fat were produced using 10 and 15% (v/v) of traditional and milk-based kombucha inoculum by application of appropriate technological process. Milk fermentation using two types and concentrations of kombucha inoculum were stopped when the pH reached 4.5. Sigmoidal fermentation profiles were noticed with traditional kombucha inoculums and linear with milk-based kombucha inoculums. Chemical content and physico-chemical characterist...

  7. Influence of packaging information on consumer liking of chocolate milk.

    Science.gov (United States)

    Kim, M K; Lopetcharat, K; Drake, M A

    2013-08-01

    Chocolate milk varies widely in flavor, color, and viscosity, and liking is influenced by these properties. Additionally, package labels (declared fat content) and brand are some of the extrinsic factors that may influence consumer perception. The objective of this study was to evaluate the effects of packaging labels and brand name on consumer liking and purchase intent of chocolate milk. A consumer acceptance test, conjoint analysis survey, and Kano analysis were conducted. One hundred eight consumers evaluated 7 chocolate milks with and without brand or package information in a 2-d crossover design. A conjoint analysis survey and Kano analysis were conducted after the consumer acceptance test. Results were evaluated by 2-way ANOVA and multivariate analyses. Declared fat content and brand influenced overall liking and purchase intent for chocolate milks to differing degrees. A subsequent conjoint analysis (n=250) revealed that fat content was a driver of choice for purchasing chocolate milk followed by sugar content and brand. Brand name was less important for purchase intent of chocolate milk than fat or sugar content. Among fat content of chocolate milk, 2 and 1% fat level were most appealing to consumers, and reduced sugar and regular sugar were equally important for purchase intent. Kano analysis confirmed that fat content (whole milk, 1, or 2% fat chocolate milk) was an attractive attribute for consumer satisfaction, more so than brand. Organic labeling did not affect the purchase decision of chocolate milk; however, Kano results revealed that having an organic label on a package positively influenced consumer satisfaction. Findings from this study can help chocolate milk producers as well as food marketers better target their product labels with attributes that drive consumer choice of chocolate milk. Copyright © 2013 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  8. Automated monitoring of milk meters

    NARCIS (Netherlands)

    Mol, de R.M.; Andre, G.

    2009-01-01

    Automated monitoring might be an alternative for periodic checking of electronic milk meters. A computer model based on Dynamic Linear Modelling (DLM) has been developed for this purpose. Two situations are distinguished: more milking stands in the milking parlour and only one milking stand in the m

  9. 7 CFR 1160.109 - Milk.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 9 2010-01-01 2009-01-01 true Milk. 1160.109 Section 1160.109 Agriculture Regulations... Orders; Milk), DEPARTMENT OF AGRICULTURE FLUID MILK PROMOTION PROGRAM Fluid Milk Promotion Order Definitions § 1160.109 Milk. Milk means any class of cow's milk produced in the United States. ...

  10. CONDUCTIVITY OF DONKEY MILK

    Directory of Open Access Journals (Sweden)

    F. Conte

    2009-06-01

    Full Text Available The electrical conductivity (EC of milk is considered as one of the most important parameters which supports the diagnosis of mastitis in cows.Milk ions have a considerable influence on EC and their concentrations vary depending on animal species, season, lactation stage, etc. Some components of milk can change the EC, e.g. lactose. A negative correlation between EC values and the concentration of lactose is noticed, as a consequence of the inverse relation between this disaccharide and the chlorine content in milk. Fat and casein contents exert some influence on the EC, too. This study provides preliminary results on the physiological EC values in donkey milk and aims to highlight any correlation with some of its chemical-physical parameters and Somatic Cell Count (SCC. Mean EC value in donkey milk was found to be 3.57 mS. Statistically significant correlations were found between EC and SCC (r = 0.57 , p < 0.01 and between EC and (r = 0.30 , p < 0.05. The EC and lactose were not correlated although a reduction of EC was often observed when the lactose content increased, as reported in the literature for bovine milk. According to the EC can be considered as a reliable parameter to identify any breast disorder, taking into account the physiological factors that influence EC.

  11. Bovine milk glycome.

    Science.gov (United States)

    Tao, N; DePeters, E J; Freeman, S; German, J B; Grimm, R; Lebrilla, C B

    2008-10-01

    Bovine milk oligosaccharides have several potentially important biological activities including the prevention of pathogen binding to the intestinal epithelial and as nutrients for beneficial bacteria. It has been suggested that milk oligosaccharides are an important source of complex carbohydrates as supplements for the food and the pharmaceutical industries. However, only a small number of structures of bovine milk oligosaccharides (bMO) are known. There have been no systematic studies on bMO. High-performance mass spectrometry and separation methods are used to evaluate bMO, and nearly 40 oligosaccharides are present in bovine milk. Bovine milk oligosaccharides are composed of shorter oligomeric chains than are those in human milk. They are significantly more anionic with nearly 70%, measured abundances, being sialylated. Additionally, bMO are built not only on the lactose core (as are nearly all human milk oligosaccharides), but also on lactose amines. Sialic acid residues include both N-acetyl and N-glycolylneuraminic acid, although the former is significantly more abundant.

  12. NMR-based milk metabolomics

    DEFF Research Database (Denmark)

    Sundekilde, Ulrik; Larsen, Lotte Bach; Bertram, Hanne Christine S.

    2013-01-01

    Milk is a key component in infant nutrition worldwide and, in the Western parts of the world, also in adult nutrition. Milk of bovine origin is both consumed fresh and processed into a variety of dairy products including cheese, fermented milk products, and infant formula. The nutritional quality...... and processing capabilities of bovine milk is closely associated to milk composition. Metabolomics is ideal in the study of the low-molecular-weight compounds in milk, and this review focuses on the recent nuclear magnetic resonance (NMR)-based metabolomics trends in milk research, including applications linking...... the milk metabolite profiling with nutritional aspects, and applications which aim to link the milk metabolite profile to various technological qualities of milk. The metabolite profiling studies encompass the identification of novel metabolites, which potentially can be used as biomarkers or as bioactive...

  13. Fermented milk for hypertension.

    Science.gov (United States)

    Usinger, Lotte; Reimer, Christina; Ibsen, Hans

    2012-04-18

    Fermented milk has been suggested to have a blood pressure lowering effect through increased content of proteins and peptides produced during the bacterial fermentation. Hypertension is one of the major risk factors for cardiovascular disease world wide and new blood pressure reducing lifestyle interventions, such as fermented milk, would be of great importance. To investigate whether fermented milk or similar products produced by lactobacilli fermentation of milk proteins has any blood pressure lowering effect in humans when compared to no treatment or placebo. The Cochrane Central Register of Controlled Trials (CENTRAL), English language databases, including MEDLINE (1966-2011), EMBASE (1974-2011), Cochrane Complementary Medicine Trials Register, Allied and Complementary Medicine (AMED) (1985-2011), Food science and technology abstracts (1969-2011). Randomised controlled trials; cross over and parallel studies evaluating the effect on blood pressure of fermented milk in humans with an intervention period of 4 weeks or longer. Data was extracted individually by two authors, afterwards agreement had to be obtained before imputation in the review. A modest overall effect of fermented milk on SBP was found (MD -2.45; 95% CI -4.30 to -0.60), no effect was evident on DBP (MD -0.67; 95% CI -1.48, 0.14). The review does not support an effect of fermented milk on blood pressure. Despite the positive effect on SBP the authors conclude, for several reasons, that fermented milk has no effect on blood pressure. The effect found was very modest and only on SBP, the included studies were very heterogeneous and several with weak methodology. Finally, sensitivity and subgroup analyses could not reproduce the antihypertensive effect. The results do not give notion to the use of fermented milk as treatment for hypertension or as a lifestyle intervention for pre-hypertension nor would it influence population blood pressure.

  14. Donor milk: current perspectives

    Directory of Open Access Journals (Sweden)

    Giuliani F

    2014-07-01

    Full Text Available Francesca Giuliani,1 Ilaria Rovelli,1 Chiara Peila,1 Stefania Alfonsina Liguori,2 Enrico Bertino,1 Alessandra Coscia1 1SCDU Neonatologia, Dipartimento di Scienze Pediatriche e dell'Adolescenza, Università degli Studi di Torino, Torino, Italy; 2SC Neonatologia, Ospedale Maria Vittoria, Torino, Italy Abstract: Mother's own milk is widely recognized as the optimal feeding for term infants, but increasing evidence exists of its benefits also for sick and preterm infants in neonatal intensive care units. However, the nutritional needs for appropriate growth and neurodevelopmental outcomes of such a particular population of infants should be attentively evaluated, considering also the indication to an appropriate fortification of human milk. The target is to achieve growth potential for preterm newborns while ensuring good metabolic outcomes and normal neurological development. When mother's milk is unavailable or in short supply, donor human milk (DHM represents the second best choice and, although somewhat modified by the Holder pasteurization process, it preserves many benefits when compared to formula, as documented by more and more reports, randomized controlled trials, and meta-analyses published in the past few years. Evidence exists of the protection exerted by DHM from necrotizing enterocolitis, while further studies are required to look at possible beneficial effects regarding infections, bronchopulmonary dysplasia, long-term cardiovascular risk factors, feeding tolerance, neurological outcome, and allergy. Finally, the concern that the use of DHM might decrease preterm infant breastfeeding is being raised. Conversely, publications exist showing that the use of DHM in the neonatal unit increases breastfeeding rates at discharge for infants of very low birth weight. Keywords: human milk, preterm infant feeding, milk bank, breast milk, mother's own milk, pasteurized human milk, fortification

  15. Fortification of maternal milk

    Directory of Open Access Journals (Sweden)

    Cecilia Di Natale

    2013-06-01

    Full Text Available The beneficial effects of human milk (HM, well recognized for the term infant, extend to the feeding of premature infants, because their nutrition support must be designed to compensate for metabolic and gastrointestinal immaturity, immunologic compromise, and maternal psycosocial conditions. Studies show that preterm milk contains higher protein levels and more fat than term human milk. The American Academy of Pediatrics recommended that preterm neonates should receive sufficient nutrients to enable them to grow at a rate similar to that of fetuses of the same gestational age. There are no doubts about the fact that maternal milk is the best food for all neonates, but unfortified human breast milk may not meet the recommended nutritional needs of growing preterm infants. Human milk must therefore be supplemented (fortified with the nutrients in short supply. The objective of fortification is to increase the concentration of nutrients to such levels that at the customary feeding volumes infants receive amounts of all nutrients that meet the requirements. The are two different forms of fortification of human milk: standard and individualized. The new concepts and recommendations for optimization of human milk fortification is the “individualized fortification”. Actually, two methods have been proposed for individualization: the “targeted/tailored fortification” and the “adjustable fortification”. In summary, the use of fortified human milk produces adequate growth in premature infants and satisfies the specific nutritional requirements of these infants. The use of individualized fortification is recommended. Proceedings of the 9th International Workshop on Neonatology · Cagliari (Italy · October 23rd-26th, 2013 · Learned lessons, changing practice and cutting-edge research

  16. PHYSIOLOGY AND GENETIC ASPECTS OF THE REGULATION OF EXPRESSION MILK PROTEIN GENES

    Directory of Open Access Journals (Sweden)

    Jozef Bulla

    2013-06-01

    Full Text Available For the genetic improvement of milk composition and milk yield, both the typing of different protein variants and knowledge about the regulation of expression of the different milk protein genes are important. Some of the processing properties of milk are dependent on the milk composition. Information about the DNA sequence and genes involved in the expression of the milk protein genes,therefore,is big importance for genetic improvement of these traits in animals breeding programmes.In recent years more data has become available concerning the regulation of expression of the milk protein genes and as might have been expected from the complex multihormonal control of these genes it appears to be rather complex. Although several mammary gland specific factors that play a role in expression of some of these genes have been identified,none of these factors has been shown to be involved in the expression of all or the majority of the milk protein genes.

  17. Near Infrared Spectroscopy (NIRS) for the determination of the milk fat fatty acid profile of goats.

    Science.gov (United States)

    Núñez-Sánchez, N; Martínez-Marín, A L; Polvillo, O; Fernández-Cabanás, V M; Carrizosa, J; Urrutia, B; Serradilla, J M

    2016-01-01

    Milk fatty acid (FA) composition is important for the goat dairy industry because of its influence on cheese properties and human health. The aim of the present work was to evaluate the feasibility of NIRS reflectance (oven-dried milk using the DESIR method) and transflectance (liquid milk) analysis to predict milk FA profile and groups of fats in milk samples from individual goats. NIRS analysis of milk samples allowed to estimate FA contents and their ratios and indexes in fat with high precision and accuracy. In general, transflectance analysis gave better or similar results than reflectance mode. Interestingly, NIRS analysis allowed direct prediction of the Atherogenicity and Thrombogenicity indexes, which are useful for the interpretation of the nutritional value of goat milk. Therefore, the calibrations obtained in the present work confirm the viability of NIRS as a fast, reliable and effective analytical method to provide nutritional information of milk samples.

  18. Molecular changes during chemical acidification of the buffalo and cow milks

    Directory of Open Access Journals (Sweden)

    F. Gaucheron

    2010-02-01

    Full Text Available Composition and physico-chemical properties of buffalo and cow milks were compared at their initial pH and during chemical acidification. As compare to cow milk, buffalo milk was richer in caseins and minerals such as Ca, Mg and Pi. Along with these differences, the capacity of buffalo milk to be acidified named buffering capacity was also higher than cow milk. The pH decrease induced aggregation of caseins at their isoelectric pH and solubilisations of Ca and Pi were significant for both milks. For both species, these molecular changes were qualitatively similar but quantitatively different. These differences suggested that the acidification process in dairy technology which is well established for cow milk can not be directly extrapolated to buffalo milk and some adaptations are necessary.

  19. Genetic parameters of different measures of cheese yield and milk nutrient recovery from an individual model cheese-manufacturing process.

    Science.gov (United States)

    Bittante, G; Cipolat-Gotet, C; Cecchinato, A

    2013-01-01

    Cheese yield (CY) is an important technological trait in the dairy industry, and the objective of this study was to estimate the genetic parameters of cheese yield in a dairy cattle population using an individual model-cheese production procedure. A total of 1,167 Brown Swiss cows belonging to 85 herds were sampled once (a maximum of 15 cows were sampled per herd on a single test day, 1 or 2 herds per week). From each cow, 1,500 mL of milk was processed according to the following steps: milk sampling and heating, culture addition, rennet addition, gelation-time recording, curd cutting, whey draining and sampling, wheel formation, pressing, salting in brine, weighing, and cheese sampling. The compositions of individual milk, whey, and curd samples were determined. Three measures of percentage cheese yield (%CY) were calculated: %CY(CURD), %CY(SOLIDS), and %CY(WATER), which represented the ratios between the weight of fresh curd, the total solids of the curd, and the water content of the curd, respectively, and the weight of the milk processed. In addition, 3 measures of daily cheese yield (dCY, kg/d) were defined, considering the daily milk yield. Three measures of nutrient recovery (REC) were computed: REC(FAT), REC(PROTEIN), and REC(SOLIDS), which represented the ratio between the weights of the fat, protein, and total solids in the curd, respectively, and the corresponding nutrient in the milk. Energy recovery, REC(ENERGY), represented the energy content of the cheese versus that in the milk. For statistical analysis, a Bayesian animal model was implemented via Gibbs sampling. The effects of parity (1 to ≥4), days in milk (6 classes), and laboratory vat (15 vats) were assigned flat priors; those of herd-test-date, animal, and residual were given Gaussian prior distributions. Intra-herd heritability estimates of %CY(CURD), %CY(SOLIDS), and %CY(WATER) ranged from 0.224 to 0.267; these were larger than the estimates obtained for milk yield (0.182) and milk fat

  20. Theoretical Study of the Effect of Multi-Diameter Distribution on the Mie Scattering Characteristics of Milk Fat

    Institute of Scientific and Technical Information of China (English)

    Jinying Yin∗; Siqi Zhang; Hongyan Yang; Zhen Zhou

    2015-01-01

    To correct the light scattering property parameters of milk fat for improving the detection accuracy, the Mie⁃theory was used to establish a predictive model for light scattering properties of milk fat globule with multi⁃diameter distributions, by means of Monte Carlo approach to simulate actual multi⁃diameter size distribution of milk fat globule in milk fat solution. Scattering coefficient and absorption coefficient of multi⁃diameter distribution milk fat particles were calculated by simulating the particles size distribution in milk fat solution. And the light scattering properties of multi⁃diameter distribution was compared with that of volume mean diameter, Sauter mean diameter and numerical mean diameter in milk fat solution. Theoretical simulation results indicate that the scattering coefficient and absorption coefficient of milk fat particles are determined by the particle size distribution in milk fat solution. There is a distinct difference in scattering characteristics between the milk fat particles with multi⁃diameter distribution and that with mean diameters. Compared to that with multi⁃diameter distribution, the scattering coefficient of the milk fat particles with mean diameter has a maximum mean deviation of 9 042 m-1 . The particle size distribution is not completely determined by the mean diameters. The dependence of the light scattering properties on the particle size distribution should be considered into the model and simulation. Therefore, it is found that the particle size distribution in milk fat solution is an essential and critical factor to significantly improve the detection accuracy of milk fat content.

  1. Pasteurization of Milk

    Directory of Open Access Journals (Sweden)

    Alejandro Barbosa Alzate

    2010-01-01

    Full Text Available We determined the time it takes milk, which is heated from 60°F to 150°F, to achieve pasteurization and compared this result with the standard pasteurization process of heating milk at a constant temperature of 150°F for 30 minutes. Instead of directly quantifying the bacterium population, we considered the bacteria to milk concentration ratio. To solve for the unknown time, we equated the final bacterium concentration ratio achieved through both varied temperature and constant temperature. After equating the final pasteurization concentrations we were unable to find an analytical solution, so we used numerical techniques to find the unknown heating time.

  2. Covariance among milking frequency, milk yield, and milk composition from automatically milked cows

    DEFF Research Database (Denmark)

    Løvendahl, Peter; Chagunda, G G

    2011-01-01

    Holsteins, Red Danes, and Jerseys in parities 1, 2, and 3. Data were analyzed using a linear mixed model, with cow-lactation as a random effect and assuming heterogeneous residual variance over the lactation. Cow-lactation variance was fitted using linear spline functions with 5 knot-points. Residual...... variance was generally greatest in early lactation and declined thereafter. Accordingly, animal-related variance tended to increase with progression of lactation. Milking frequency (the reverse of milking interval) was found to be moderately repeatable throughout lactation. Daily milk yield expressed per...

  3. Correlation between whole and partial milk yields of dairy cows milked using the automatic milking system

    Directory of Open Access Journals (Sweden)

    Gustav Chládek

    2009-01-01

    Full Text Available The objective was to quantify the correlations between milk indicators of partial milk yields and whole milk output; we analysed 576 milk samples taken from 2 to 4 partial milk yields of 156 Holstein dairy cows milked using the automatic milking system (AMS. In the accredited (EN ISO 17025 milk laboratory in Brno–Tuřany the samples were analysed for the content of fat (T; g . 100g−1, crude protein (B; g . 100g−1, lactose (L; lactose monohydrate; g . 100g−1 and somatic cell count (SCC; 103.ml−1. The average values in the whole milk output were as follows: T = 3.69 g . 100g−1, B = 3.39 g . 100g−1, L = 4.92 g . 100g−1, PSB = 345.103 ml−1 and log SCC = 1.9695, at a whole milk output of 29.88 kg.day1 of milk. The correlation coefficients between the milk indicators (T, B, L, PSB and log PSB of partial milk yields and whole milk output ranged from the minimum r = 0.786 (between the content of T in the whole and 3rd milk yield to the maximum r = 0.979 (between the content of B in the whole milk output and identically in the 1st, 3rd and 4th milk yields and in all cases they were statistically highly significant (P ≤ 0.001. Next we calculated the regression equations for the estimation of milk indicators of the whole milk output from milk indicators of the 1st to 4th partial milk yields.

  4. Condensed milk storage and evaporation affect the flavor of nonfat dry milk.

    Science.gov (United States)

    Park, Curtis W; Drake, MaryAnne

    2016-12-01

    Unit operations in nonfat dry milk (NFDM) manufacture influence sensory properties, and consequently, its use and acceptance in ingredient applications. Condensed skim milk may be stored at refrigeration temperatures for extended periods before spray drying due to shipping or lack of drying capacity. Currently, NFDM processors have 2 options for milk concentration up to 30% solids: evaporation (E) or reverse osmosis (RO). The objective of this study was to determine the effect of condensed milk storage and milk concentration method (E vs. RO) on the flavor of NFDM and investigate mechanisms behind flavor differences. For experiment 1, skim milk was pasteurized and concentrated to 30% solids by E or RO and then either stored for 24h at 4°C or concentrated to 50% solids by E and spray dried immediately. To investigate mechanisms behind the results from experiment 1, experiment 2 was constructed. In experiment 2, pasteurized skim milk was subjected to 1 of 4 treatments: control (no E), heated in the evaporator without vacuum, E concentration to 30% solids, or E concentration to 40% solids. The milks were then diluted to the same solids content and evaluated. Volatile compounds were also measured during concentration in the vapor separator of the evaporator. Sensory properties were evaluated by descriptive sensory analysis and instrumental volatile compound analysis was conducted to evaluate volatile compounds. Interaction effects between storage and method of concentration were investigated. In experiment 1, E decreased sweet aromatic flavor and many characteristic milk flavor compounds and increased cardboard and cooked flavors in NFDM compared with RO. Liquid storage increased cardboard flavor and hexanal and octanal and decreased sweet aromatic flavors and vanillin concentration. Results from experiment 2 indicated that the characteristic milk flavors and their associated volatile compounds were removed by the vapor separator in the evaporator due to the heat and

  5. Effect of tiger-nut (Cyperus esculentus) milk co-product on the surface and diffusional properties of a wheat-based matrix.

    Science.gov (United States)

    Verdú, Samuel; Barat, José M; Alava, Cecibel; Grau, Raúl

    2017-06-01

    The food processing industry generates huge volumes of waste and co-products which still contain valuable compounds. Tiger-nut milk production generates large amounts of a co-product with a high insoluble fibre content, which is interesting as a bioactive component from a nutritional viewpoint. This co-product is formed by two different tissues in composition, particle size and colour terms, so two different flours were obtained from them. Both flours were included in a wheat-based matrix at different substitution levels: 5%, 10% and 20% (d.b). The surface tension of matrices, and the wettability and diffusion of water and oil, were studied. The results showed the matrix's reduced capacity to interact with solvents, principally from the 10% substitution level, with diminished surface tension, and a longer time was needed for both water and oil to wet and diffuse.

  6. Expanding the bovine milk proteome through extensive fractionation.

    Science.gov (United States)

    Nissen, Asger; Bendixen, Emøke; Ingvartsen, Klaus Lønne; Røntved, Christine Maria

    2013-01-01

    Bovine milk is an agricultural product of tremendous value worldwide. It contains proteins, fat, lactose, vitamins, and minerals. It provides nutrition and immunological protection (e.g., in the gastrointestinal tract) to the newborn and young calf. It also forms an important part of human nutrition. The repertoire of proteins in milk (i.e., its proteome) is vast and complex. The milk proteome can be described in detail by mass spectrometry-based proteomics. However, the high concentration of dominating proteins in milk reduces mass spectrometry detection sensitivity and limits detection of low abundant proteins. Further, the general health and udder health of the dairy cows delivering the milk may influence the composition of the milk proteome. To gain a more exhaustive and true picture of the milk proteome, we performed an extensive preanalysis fractionation of raw composite milk collected from documented healthy cows in early lactation. Four simple and industrially applicable techniques exploring the physical and chemical properties of milk, including acidification, filtration, and centrifugation, were used for separation of the proteins. This resulted in 5 different fractions, whose content of proteins were compared with the proteins of nonfractionated milk using 2-dimensional liquid chromatography tandem mass spectrometry analysis. To validate the proteome analysis, spectral counts and ELISA were performed on 7 proteins using the ELISA for estimation of the detection sensitivity limit of the 2-dimensional liquid chromatography tandem mass spectrometry analysis. Each fractionation technique resulted in identification of a unique subset of proteins. However, high-speed centrifugation of milk to whey was by far the best method to achieve high and repeatable proteome coverage. The total number of milk proteins initially detected in nonfractionated milk and the fractions were 635 in 2 replicates. Removal of dominant proteins and filtering for redundancy across the

  7. Milking Efficiency – A Milkability Trait for Automatically Milked Cows

    DEFF Research Database (Denmark)

    Løvendahl, Peter; Lassen, Jan; Chagunda, M G G

    Data from an experimental herd with automatic milkings from 486 first lactation cows were used to study alternative measures of milkability. One trait was milking efficiency, (kg milk per minute used in robot) the other “residual milking box time” using a linear regression to adjust daily time...... efficiency which showed only intermediate correlation. Both traits had weak correlations to somatic cell counts. It is concluded that either trait will be effective in selecting for cows giving more milk per minute occupying the milking robot, without increasing risk of mastitis...... for daily fat and protein corrected yield. Both traits were moderate to highly heritable and closely correlated (ra = 0.85). The two traits differed by milking efficiency being correlated to yield (ra = 0.48). Residual box time was closely correlated to milking time (ra = 0.93) compared to milking...

  8. Steam-frothing of milk for coffee

    DEFF Research Database (Denmark)

    Münchow, Morten; Jørgensen, Leif; Amigo Rubio, Jose Manuel

    2015-01-01

    A method for evaluation of the foaming properties of steam-frothed milk, based on image analysis (feature extraction) carried out on a video taken immediately after foam formation, was developed. The method was shown to be able to analyse steam-frothed milk made using a conventional espresso...... machine, such as commonly used by baristas. Samples of milk, processed in a commercial dairy plant, were made with varying fat (0.5%, 0.9%, 1.5%, 2.6%, 3.5%) or protein (3.0%, 3.4%. 3.8%) content and analysed using the developed method. Increased protein content was shown to cause a delay in the formation...

  9. Colostrum and milk production

    DEFF Research Database (Denmark)

    Quesnel, H; Theil, Peter Kappel

    2015-01-01

    for the sow. More specifically, fetal growth, mammary growth, colostrum production and sow maintenance require substantial amounts of nutrients during late gestation. After parturition, nutrients are mainly required for milk synthesis and sow maintenance, but the regressing uterus supplies considerable...... becomes catabolic due to the high priority of milk production and to current feeding practices. Indeed, feed is changed from a gestation to a lactation diet for most sows and the feed supply typically goes from a restricted supply to an ad libitum allowance. In addition, transition sows are often exposed...... to shifts in housing, and in Europe, this shift is now associated with a change from loose group housing to individual housing. Around parturition, colostrum is being secreted and milk synthesis is initiated in the mammary glands. After the onset of lactation, milk composition changes, especially during...

  10. Analysis of Milk Oligosaccharides by Mass Spectrometry.

    Science.gov (United States)

    Wu, Lauren D; Ruhaak, L Renee; Lebrilla, Carlito B

    2017-01-01

    Human milk oligosaccharides (HMOs) are a highly abundant constituent in human milk, and its protective and prebiotic properties have attracted considerable attention. HMOs have been shown to directly and indirectly benefit the overall health of the infant due to a number of functions including serving as a beneficial food for gut bacteria, block to pathogens, and aiding in brain development. Researchers are currently exploring whether these structures may act as possible disease and nutrition biomarkers. Because of this, rapid-throughput methods are desired to investigate biological activity in large patient sets. We have optimized a rapid-throughput protocol to analyze human milk oligosaccharides using micro-volumes of human breast milk for nutritional biomarkers. This method may additionally be applied to other biological fluid substrates such as plasma, urine, and feces. The protocol involves lipid separation via centrifugation, protein precipitation using ethanol, alditol reduction with sodium borohydride, and a final solid-phase extraction purification step using graphitized carbon cartridges. Samples are analyzed using HPLC-Chip/TOF-MS and data filtered on Agilent MassHunter using an in-house library. Individual structural identification is matched against a previously developed HMO library using accurate mass and retention time. Using this method will allow in-depth characterization and profiling of HMOs in large patient sets, and will ease the process of discovering significant nutritional biomarkers in human milk.

  11. 复合凝乳酶胶囊治疗儿童胃肠功能障碍的临床研究%The clinical research on the application of compound rennet capsules into neonatal patients with gastrointestinal dysfunction

    Institute of Scientific and Technical Information of China (English)

    宋元华

    2015-01-01

    Objective To explore the applicational effect of composite rennet capsules for the treatment of infantile gastric dysfunction, so as to provide effective prevention and control of pediatric gastrointestinal dysfunction.Methods 76 newborn children with gastrointestinal dysfunction hospitalized in our hospital were randomly divided into two groups, with the experimental group using compound rennet capsule on the basis of conventional treatment and the control group treated with conventional method, and then the symptoms score and the curative effect of the two groups before and after treatment were compared. Results The symptoms score of these two groups both decreased, but the group given the application of composite rennet capsules were much more lower than that of the group with conventional treatment; besides, the the total effective rate of the neonatal patients who used composite rennet treatment was 94.7%, and the total effective rate of the conventional treatment group of children was 81.6%, with statistically significant difference(P< 0.05).Conclusion On the basis of conventional therapy, children with the application of composite rennet capsule treatment of pediatric gastrointestinal dysfunction improve significantly more than those with conventional treatment, and the application of composite rennet capsule treatment proves to be more practical, convenient and safe than conventional treatment and without any side effects.%目的 探讨研究复合凝乳酶胶囊治疗儿童胃功能障碍的临床效果.方法 将76例胃肠道功能障碍的患儿随机分为两组,试验组在常规治疗的基础上使用复合凝乳酶胶囊,对照组用常规治疗的方法,然后将两组治疗前后症状积分和两组的治疗效果进行比较.结果 两组的治疗症状积分均下降,但应用复合凝乳酶胶囊要比常规治疗下降更为显著;且使用复合凝乳酶治疗的患儿治疗后的总有效率为94.7%,而常规治疗

  12. Real-time evaluation of individual cow milk for higher cheese-milk quality with increased cheese yield.

    Science.gov (United States)

    Katz, G; Merin, U; Bezman, D; Lavie, S; Lemberskiy-Kuzin, L; Leitner, G

    2016-06-01

    Cheese was produced in a series of experiments from milk separated in real time during milking by using the Afilab MCS milk classification service (Afikim, Israel), which is installed on the milk line in every stall and sorts milk in real time into 2 target tanks: the A tank for cheese production (CM) and the B tank for fluid milk products (FM). The cheese milk was prepared in varying ratios ranging from ~10:90 to ~90:10 CM:FM by using this system. Cheese was made with corrected protein-to-fat ratio and without it, as well as from milk stored at 4°C for 1, 2, 3, 4, and 8d before production. Cheese weight at 24h increased along the separation cutoff level with no difference in moisture, and dry matter increased. The data compiled allowed a theoretical calculation of cheese yield and comparing it to the original van Slyke equation. Whenever the value of Afi-Cf, which is the optical measure of curd firmness obtained by the Afilab instrument, was used, a better predicted level of cheese yield was obtained. In addition, 27 bulk milk tanks with milk separated at a 50:50 CM:FM ratio resulted in cheese with a significantly higher fat and protein, dry matter, and weight at 24h. Moreover, solids incorporated from the milk into the cheese were significantly higher in cheeses made of milk from A tanks. The influence of storage of milk up to 8d before cheese making was tested. Gross milk composition did not change and no differences were found in cheese moisture, but dry matter and protein incorporated in the cheese dropped significantly along the storage time. These findings confirm that milk stored for several days before processing is prone to physico-chemical deterioration processes, which result in loss of milk constituents to the whey and therefore reduced product yield. The study demonstrates that introducing the unknown parameters for calculating the predicted cheese yield, such as the empiric measured Afi-Cf properties, are more accurate and the increase in cheese

  13. Effect of Addition of Salt, Milk and Sucrose on Mechanical Property of Wheat Gluten%外源添加食盐、牛奶和蔗糖对小麦面筋力学特性的影响

    Institute of Scientific and Technical Information of China (English)

    贾峰; 柳甜甜; 王震磊; 周晓配; 刘霄龙; 王金水

    2016-01-01

    This article studied the effects of adding salt, milk or sugar on mechanical properties of wheat gluten in weak, medium and strong gluten wheat lfour, respectively. The results showed that it could improve the hardness of gluten and gluten viscoelasticity in the dough to add a small amount of salt, and improve the mechanical properties of the flour. It had little effect on the hardness of gluten to add some sugar in the dough. However, it had greatly reduced the gluten viscoelasticity and weakened the mechanical properties of gluten. It could improve the hardness of gluten in the dough to add a certain amount of milk, especially the gluten hardness of low gluten lfour, and improve gluten viscoelasticity, especially the viscous properties of gluten.%以强筋、中筋和弱筋三种不同筋力的小麦面粉为材料,研究了添加食盐、蔗糖和牛奶等外源物质对小麦粉面筋力学特性的影响。结果表明:在面粉中添加少量的食盐,可以提高面筋的硬度和面筋的黏弹性,有助于改善面团的力学特性;在面粉中添加一些蔗糖,对于面筋的硬度影响不大,但却较大幅度降低面筋的黏弹性,弱化面筋的力学特性;在面粉中添加一定量的牛奶,可以提高面筋的硬度,尤其是低筋粉的面筋硬度,并有助于提高面筋的黏弹性,特别是面筋的黏性。

  14. alpha-1-antitrypsin in breast milk of healthy Nigerian mothers.

    Science.gov (United States)

    Omeme, J A; Lantos, J D; Ihongbe, J C

    1981-01-01

    Alpha-1-antitryspin (x-1-AT) may play a possible role as effector of immunological stasis. This study examines the levels of this glycoprotein in 73 breast milk samples from 60 healthy Nigerian mothers. Levels of x-1-AT were measured by single radial immunodiffusion according to the method of Mancini. Serum protein was measured by Lowry's method, albumin by Doumas' method. Highest mean levels of x-1-AT were found in colostrum (25 mg/dl). The level was significantly higher compared to transitional milk (14.2 mg/dl) or mature milk (165 mg/dl) (p0.001). Breast milk contains substantial amounts of x-1-AT which is not destroyed by pasturization at 56 degrees Centigrade. The immunological protective properties of breast milk are ideal for newborn babies, particularly those who are low birthweight and are thus most susceptible to neonatal necrotizing enterocolitis.

  15. Microbiological and physicochemical characterization of milk according to the seasons

    Directory of Open Access Journals (Sweden)

    Rafael Fagnani

    2014-06-01

    Full Text Available The seasons have a major influence on milk production, especially when animals are exposed to climatic variations. This situation is very common in Brazil and further investigation is needed to understand the losses caused by oscillations in milk constituents. The aim was to evaluate how seasonality can affect the physicochemical and microbiological quality of raw milk in Ivaiporã region, state of Paraná, Brazil. In this research, the milk from properties in northern Paraná was evaluated during 24 months for lactose, protein, fat, total solids, total bacteria count and somatic cell count. The regional rainfall and average temperature recorded at each station were analyzed for determination of Thermal Comfort Index and evaluation of heat stress. This study concluded that seasonality have influence on microbiological and physicochemical quality of milk in Ivaiporã region, with higher percentages of solids in the fall and inferior microbiological quality in the spring.

  16. Analysis and Application of Whey Protein Depleted Skim Milk Systems

    DEFF Research Database (Denmark)

    Sørensen, Hanne

    homogenisation (UHPH). The microfiltration will result in a milk fraction more or less depleted from whey protein, and could probably in combination with UHPH treatment contribute to milk fractions and cheeses with novel micro and macrostructures. These novel fractions could be used as new ingredients to improve......-destructive methods for this purpose. A significant changed structure was observed in skim milk depleted or partly depleted for whey protein, acidified and UHPH treated. Some of the properties of the UHPH treated skim milk depleted from whey protein observed in this study support the idea, that UHPH treatment has...... this. LF-NMR relaxation were utilised to obtain information about the water mobility (relaxation time), in diluted skim milk systems depleted from whey protein. Obtained results indicate that measuring relaxation times with LF-NMR could be difficult to utilize, since no clear relationship between...

  17. Microarray analysis applied to the study of milk protein loci in cattle

    Directory of Open Access Journals (Sweden)

    G. Pagnacco

    2010-01-01

    Full Text Available Milk proteins still arise much interest because of the proved effects of the most common milk genetic polymorphisms on quantitative and qualitative milk production, as well as on milk technological properties. The role of αs1-casein (CSN1S1, β-casein (CSN2, k-casein (CSN3 and β-lactoglobulin (LGB polymorphisms in the genetic improvement of milk production was already demonstrated in cattle, as reviewed by Di Stasio and Mariani (2000 and Martin et al. (2002.

  18. Potential of quixaba (Sideroxylon obtusifolium latex as a milk-clotting agent

    Directory of Open Access Journals (Sweden)

    Anna Carolina da Silva

    2013-09-01

    Full Text Available There are several obstacles to the use of chymosin in cheese production. Consequently, plant proteases have been studied as possible rennet substitutes, but most of these enzymes are unsuitable for the manufacture of cheese. The aim of this study was to evaluate the potential of latex from Sideroxylon obtusifolium as a source of milk-clotting proteases and to partially characterize the enzyme. The enzyme extract showed high protease and coagulant activities, with an optimal pH of 8.0 and temperature of 55 °C. The enzyme was stable in wide ranges of temperature and pH. Its activity was not affected by any metal ions tested; but was inhibited by phenylmethanesulfonyl fluoride and pepstatin. For the coagulant activity, the optimal concentration of CaCl2 was 10 µmol L- 1. Polyacrylamide gel electrophoresis showed four bands, with molecular weights between 17 and 64 kDa. These results indicate that the enzyme can be applied to the cheese industry.

  19. Optimization of the production and characterization of milk clotting enzymes by Bacillus subtilis natto.

    Science.gov (United States)

    Wu, Fang-Chen; Chang, Chen-Wei; Shih, Ing-Lung

    2013-12-01

    Suitable medium for production of milk clotting enzyme (MCE) by Bacillus subtilis (natto) Takahashi in submerged liquid-state fermentation was screened, the nutrient factors affecting MCE production was optimized by response surface methodology. The MCE production by B. subtilis (natto) Takahashi was increased significantly by 428% in the optimal medium developed. The MCE was filtered and concentrated by ultrafiltration. The retentate after tandem filtration carried out with the combined membranes of MWCO 50kDa and 5 kDa showed two major bands between 25kDa and 30kDa on SDS-PAGE, and the MCA and MCA/PA improved significantly in comparison with those in the initial broth. The crude enzyme thus obtained showed MCA and MCA/PA ratio of 48,000 SU/g and 6,400, which are commensurate with those (MCA 26,667 SU/g and MCA/PA 6,667) of the commercial rennet. It had optimal pH and temperature at pH 6 and 60°C, and showed excellent pH and thermal stability.

  20. Cow's Milk Contamination of Human Milk Purchased via the Internet.

    Science.gov (United States)

    Keim, Sarah A; Kulkarni, Manjusha M; McNamara, Kelly; Geraghty, Sheela R; Billock, Rachael M; Ronau, Rachel; Hogan, Joseph S; Kwiek, Jesse J

    2015-05-01

    The US Food and Drug Administration recommends against feeding infants human milk from unscreened donors, but sharing milk via the Internet is growing in popularity. Recipient infants risk the possibility of consuming contaminated or adulterated milk. Our objective was to test milk advertised for sale online as human milk to verify its human origin and to rule out contamination with cow's milk. We anonymously purchased 102 samples advertised as human milk online. DNA was extracted from 200 μL of each sample. The presence of human or bovine mitochondrial DNA was assessed with a species-specific real-time polymerase chain reaction assay targeting the nicotinamide adenine dinucleotide (NADH) dehydrogenase subunit 5 gene. Four laboratory-created mixtures representing various dilutions of human milk with fluid cow's milk or reconstituted infant formula were compared with the Internet samples to semiquantitate the extent of contamination with cow's milk. All Internet samples amplified human DNA. After 2 rounds of testing, 11 samples also contained bovine DNA. Ten of these samples had a level of bovine DNA consistent with human milk mixed with at least 10% fluid cow's milk. Ten Internet samples had bovine DNA concentrations high enough to rule out minor contamination, suggesting a cow's milk product was added. Cow's milk can be problematic for infants with allergy or intolerance. Because buyers cannot verify the composition of milk they purchase, all should be aware that it might be adulterated with cow's milk. Pediatricians should be aware of the online market for human milk and the potential risks. Copyright © 2015 by the American Academy of Pediatrics.

  1. Milk Enhancements Improve Milk Consumption and Increase Meal Participation in the NSLP: The School Milk Pilot Test

    Science.gov (United States)

    Rafferty, Karen; Zipay, Diane; Patey, Camellia; Meyer, Jennifer

    2009-01-01

    Purpose/Objectives: The objective of the School Milk Pilot Test and the Westside School Milk Pilot Study was to test the effect of a milk enhancement initiative to make milk more appealing and attractive to elementary and secondary school students and to improve milk consumption. Methods: 146 schools participated in the national School Milk Pilot…

  2. Milk Enhancements Improve Milk Consumption and Increase Meal Participation in the NSLP: The School Milk Pilot Test

    Science.gov (United States)

    Rafferty, Karen; Zipay, Diane; Patey, Camellia; Meyer, Jennifer

    2009-01-01

    Purpose/Objectives: The objective of the School Milk Pilot Test and the Westside School Milk Pilot Study was to test the effect of a milk enhancement initiative to make milk more appealing and attractive to elementary and secondary school students and to improve milk consumption. Methods: 146 schools participated in the national School Milk Pilot…

  3. Comparison of microbiological loads and physicochemical properties of raw milk treated with single-/multiple-cycle high hydrostatic pressure and ultraviolet-C light

    Science.gov (United States)

    Hu, Guanglan; Zheng, Yuanrong; Wang, Danfeng; Zha, Baoping; Liu, Zhenmin; Deng, Yun

    2015-07-01

    The effects of ultraviolet-C radiation (UV-C, 11.8 W/m2), single-cycle and multiple-cycle high hydrostatic pressure (HHP at 200, 400 or 600 MPa) on microbial load and physicochemical quality of raw milk were evaluated. Reductions of aerobic plate count (APC) and coliform count (CC) by HHP were more than 99.9% and 98.7%, respectively. Inactivation efficiency of microorganisms increased with pressure level. At the same pressure level, two-cycle treatments caused lower APC, but did not show CC differences compared with single-cycle treatments. Reductions of APC and CC by UV-C were somewhere between 200 MPa and 400/600 MPa. Both HHP and UV-C significantly decreased lightness and increased pH, but did not change soluble solids content and thiobarbituric acid-reactive substances' values. Two 2.5 min cycles of HHP at 600 MPa caused minimum APC and CC, and maximum conductivity. Compared with HHP, UV-C markedly increased protein oxidation and reduced darkening.

  4. Composition, thermotropic properties, and oxidative stability of freeze-dried and spray-dried milk fat globule membrane isolated from cheese whey.

    Science.gov (United States)

    Zhu, Dan; Damodaran, Srinivasan

    2011-08-24

    The milk fat globule membrane (MFGM) was isolated from cheese whey using a recently developed novel method. The cheese-derived MFGM contained about 17-19% lipids and 65-70% protein on a dry weight basis. About 50% of the lipids in MFGM were phospholipids. Compositional analysis of the cheese whey-derived MFGM showed that it is a rich source of phosphatidylserine, sphingomyelin, and bioactive proteins CD36, butyrophilin, xanthine oxidase, and mucin 1. Utilization of MFGM in foods as a source of nutraceutical lipids depends on its oxidative stability. In this context, the impact of drying methods, namely, freeze-drying versus spray-drying, on the storage stability of MFGM was studied. Freeze-dried (FD) and spray-dried (SD) MFGM samples were morphologically very different when examined by light microscope: The thermotropic phase transition temperature (T(m)) of lipids in the FD-MFGM was 37.8 °C, and it was 48 °C in SD-MFGM. This 10 °C difference in T(m) indicated that the drying method altered the thermodynamic state of phospholipids in MFGM. At all storage temperatures studied, the zero-order rate constant of lipid oxidation, as measured by hexanal production, was 1-2 orders of magnitude greater in the spray-dried than in the freeze-dried MFGM. The results clearly indicated that the choice of drying method affects morphological characteristics, the T(m) and oxidative stability of phospholipids in MFGM.

  5. Pellet-free isolation of human and bovine milk extracellular vesicles by size-exclusion chromatography

    Science.gov (United States)

    Blans, Kristine; Hansen, Maria S.; Sørensen, Laila V.; Hvam, Michael L.; Howard, Kenneth A.; Möller, Arne; Wiking, Lars; Larsen, Lotte B.; Rasmussen, Jan T.

    2017-01-01

    ABSTRACT Studies have suggested that nanoscale extracellular vesicles (EV) in human and bovine milk carry immune modulatory properties which could provide beneficial health effects to infants. In order to assess the possible health effects of milk EV, it is essential to use isolates of high purity from other more abundant milk structures with well-documented bioactive properties. Furthermore, gentle isolation procedures are important for reducing the risk of generating vesicle artefacts, particularly when EV subpopulations are investigated. In this study, we present two isolation approaches accomplished in three steps based on size-exclusion chromatography (SEC) resulting in effective and reproducible EV isolation from raw milk. The approaches do not require any EV pelleting and can be applied to both human and bovine milk. We show that SEC effectively separates phospholipid membrane vesicles from the primary casein and whey protein components in two differently obtained casein reduced milk fractions, with one of the fractions obtained without the use of ultracentrifugation. Milk EV isolates were enriched in lactadherin, CD9, CD63 and CD81 compared to minimal levels of the EV-marker proteins in other relevant milk fractions such as milk fat globules. Nanoparticle tracking analysis and electron microscopy reveals the presence of heterogeneous sized vesicle structures in milk EV isolates. Lipid analysis by thin layer chromatography shows that EV isolates are devoid of triacylglycerides and presents a phospholipid profile differing from milk fat globules surrounded by epithelial cell plasma membrane. Moreover, the milk EV fractions are enriched in RNA with distinct and diverging profiles from milk fat globules. Collectively, our data supports that successful milk EV isolation can be accomplished in few steps without the use of ultracentrifugation, as the presented isolation approaches based on SEC effectively isolates EV in both human and bovine milk. PMID:28386391

  6. Use of milk-based kombucha inoculum for milk fermentation

    Directory of Open Access Journals (Sweden)

    Kolarov Ljiljana A.

    2009-01-01

    Full Text Available In this investigation fermented milk beverages with 0.9% of milk fat were produced using 10 and 15% (v/v of traditional and milk-based kombucha inoculum by application of appropriate technological process. Milk fermentation using two types and concentrations of kombucha inoculum were stopped when the pH reached 4.5. Sigmoidal fermentation profiles were noticed with traditional kombucha inoculums and linear with milk-based kombucha inoculums. Chemical content and physico-chemical characteristics of kombucha fermented milk beverages were typical and yoghurt-like for all obtained products. The best textural and sensory characteristics possesed beverage obtained in fermentation of milk using 10% (v/v of milk-based kombucha inoculum.

  7. Organic Milk Quality in the Netherlands : Distinguishable from conventional milk?

    NARCIS (Netherlands)

    Hospers-Brands, A.J.T.M.; Burgt, van der G.J.H.M.

    2009-01-01

    Recent studies have indicated possible positive interactions between organic animal production and, particularly, and various vitamins. As possible distinguishing quality parameters for organic milk, the differences between organic and conventional milk in Netherlands for fatty acid composition and

  8. Human milk banks: lights and shadows

    Directory of Open Access Journals (Sweden)

    Arianna Aceti

    2014-06-01

    Full Text Available Breastfeeding is the most appropriate source of nutrition also for preterm infants. When mother’s own milk is not available, donor human milk (DHM, provided from a human milk bank (HMB, or formula can be used. Infants fed DHM grow at a slower rate than formula-fed infants. However, DHM has the advantage over formula to retain some of the bioactive properties of naïve human milk. Given the wide variability of DHM content and its generally low macronutrient content, individualised fortification represents a more valid option than standard fortification in order to meet the high nutritional requirements of preterm infants. Pasteurization is necessary to reduce bacterial count in DHM. Holder pasteurization, which is recommended in most HMB guidelines, has several limitations, because it impairs macronutrient and functional components of DHM. Alternative methods of pasteurization, which would be capable of retaining the bioactive properties of DHM with the highest level of microbiological safety, are currently under investigation. Proceedings of the 10th International Workshop on Neonatology · Cagliari (Italy · October 22nd-25th, 2014 · The last ten years, the next ten years in Neonatology Guest Editors: Vassilios Fanos, Michele Mussap, Gavino Faa, Apostolos Papageorgiou 

  9. NMR-Based Milk Metabolomics

    Directory of Open Access Journals (Sweden)

    Hanne C. Bertram

    2013-04-01

    Full Text Available Milk is a key component in infant nutrition worldwide and, in the Western parts of the world, also in adult nutrition. Milk of bovine origin is both consumed fresh and processed into a variety of dairy products including cheese, fermented milk products, and infant formula. The nutritional quality and processing capabilities of bovine milk is closely associated to milk composition. Metabolomics is ideal in the study of the low-molecular-weight compounds in milk, and this review focuses on the recent nuclear magnetic resonance (NMR-based metabolomics trends in milk research, including applications linking the milk metabolite profiling with nutritional aspects, and applications which aim to link the milk metabolite profile to various technological qualities of milk. The metabolite profiling studies encompass the identification of novel metabolites, which potentially can be used as biomarkers or as bioactive compounds. Furthermore, metabolomics applications elucidating how the differential regulated genes affects milk composition are also reported. This review will highlight the recent advances in NMR-based metabolomics on milk, as well as give a brief summary of when NMR spectroscopy can be useful for gaining a better understanding of how milk composition is linked to nutritional or quality traits.

  10. Optimization of processing technology of black soybean-milk cheese by response surface methodology%响应面法优化黑豆干酪工艺条件

    Institute of Scientific and Technical Information of China (English)

    谭淑君; 蒋爱民; 胡利辉

    2011-01-01

    采用Box-Behnken中心组合响应面试验,研究黑豆干酪的最佳工艺条件,建立氯化钙添加量、凝乳酶添加量以及凝乳温度对凝乳效果影响的二次多项回归模型,并验证模型的有效性.结果表明,黑豆干酪的最佳工艺条件:氯化钙添加量0.06%、凝乳酶添加量0.025%、凝乳温度32℃.此时模型预测凝乳效果评分为88.5,验证实验结果为88.0,与理论预测值基本吻合.%Box-Behnken response surface methodology was employed to optimize processing technology of black soybean-milk cheese. And the second order quadratic equation for amount of calcium chloride,a-mount of rennet, curd temperature was built and the applicability of the model equation was verified. The result of response surface showed that the optimum process parameters for black soybean-milk cheese as: amount of calcium 0. 06%,amount of rennet 0. 025%, curd temperature 32 ℃ and the model gave the prediction of 88. 5. The confirmatory test showed that the curd effect was 88, and fitted the predicted value.

  11. 7 CFR 1032.13 - Producer milk.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 9 2010-01-01 2009-01-01 true Producer milk. 1032.13 Section 1032.13 Agriculture... and Orders; Milk), DEPARTMENT OF AGRICULTURE MILK IN THE CENTRAL MARKETING AREA Order Regulating Handling Definitions § 1032.13 Producer milk. Producer milk means the skim milk (or the skim equivalent of...

  12. 7 CFR 1006.13 - Producer milk.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 9 2010-01-01 2009-01-01 true Producer milk. 1006.13 Section 1006.13 Agriculture... and Orders; Milk), DEPARTMENT OF AGRICULTURE MILK IN THE FLORIDA MARKETING AREA Order Regulating Handling Definitions § 1006.13 Producer milk. Producer milk means the skim milk (or the skim equivalent of...

  13. 21 CFR 131.130 - Evaporated milk.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Evaporated milk. 131.130 Section 131.130 Food and... CONSUMPTION MILK AND CREAM Requirements for Specific Standardized Milk and Cream § 131.130 Evaporated milk. (a) Description. Evaporated milk is the liquid food obtained by partial removal of water only from milk. It...

  14. 7 CFR 1131.13 - Producer milk.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 9 2010-01-01 2009-01-01 true Producer milk. 1131.13 Section 1131.13 Agriculture... and Orders; Milk), DEPARTMENT OF AGRICULTURE MILK IN THE ARIZONA MARKETING AREA Order Regulating Handling Definitions § 1131.13 Producer milk. Producer milk means the skim milk (or the skim equivalent of...

  15. 21 CFR 131.110 - Milk.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Milk. 131.110 Section 131.110 Food and Drugs FOOD... CONSUMPTION MILK AND CREAM Requirements for Specific Standardized Milk and Cream § 131.110 Milk. (a) Description. Milk is the lacteal secretion, practically free from colostrum, obtained by the complete milking...

  16. 7 CFR 58.137 - Excluded milk.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 3 2010-01-01 2010-01-01 false Excluded milk. 58.137 Section 58.137 Agriculture... Milk § 58.137 Excluded milk. A plant shall not accept milk from a producer if: (a) The milk has been in...) Three of the last five milk samples have exceeded the maximum bacterial estimate of 500,000 per ml...

  17. 7 CFR 1001.13 - Producer milk.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 9 2010-01-01 2009-01-01 true Producer milk. 1001.13 Section 1001.13 Agriculture... and Orders; Milk), DEPARTMENT OF AGRICULTURE MILK IN THE NORTHEAST MARKETING AREA Order Regulating Handling Definitions § 1001.13 Producer milk. Producer milk means the skim milk (or the skim equivalent of...

  18. 7 CFR 1126.13 - Producer milk.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 9 2010-01-01 2009-01-01 true Producer milk. 1126.13 Section 1126.13 Agriculture... and Orders; Milk), DEPARTMENT OF AGRICULTURE MILK IN THE SOUTHWEST MARKETING AREA Order Regulating Handling Definitions § 1126.13 Producer milk. Producer milk means the skim milk (or the skim equivalent of...

  19. 7 CFR 1033.13 - Producer milk.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 9 2010-01-01 2009-01-01 true Producer milk. 1033.13 Section 1033.13 Agriculture... and Orders; Milk), DEPARTMENT OF AGRICULTURE MILK IN THE MIDEAST MARKETING AREA Order Regulating Handling Definitions § 1033.13 Producer milk. Producer milk means the skim milk (or the skim equivalent of...

  20. Prion protein in milk.

    Directory of Open Access Journals (Sweden)

    Nicola Franscini

    Full Text Available BACKGROUND: Prions are known to cause transmissible spongiform encephalopathies (TSE after accumulation in the central nervous system. There is increasing evidence that prions are also present in body fluids and that prion infection by blood transmission is possible. The low concentration of the proteinaceous agent in body fluids and its long incubation time complicate epidemiologic analysis and estimation of spreading and thus the risk of human infection. This situation is particularly unsatisfactory for food and pharmaceutical industries, given the lack of sensitive tools for monitoring the infectious agent. METHODOLOGY/PRINCIPAL FINDINGS: We have developed an adsorption matrix, Alicon PrioTrap, which binds with high affinity and specificity to prion proteins. Thus we were able to identify prion protein (PrP(C--the precursor of prions (PrP(Sc--in milk from humans, cows, sheep, and goats. The absolute amount of PrP(C differs between the species (from microg/l range in sheep to ng/l range in human milk. PrP(C is also found in homogenised and pasteurised off-the-shelf milk, and even ultrahigh temperature treatment only partially diminishes endogenous PrP(C concentration. CONCLUSIONS/SIGNIFICANCE: In view of a recent study showing evidence of prion replication occurring in the mammary gland of scrapie infected sheep suffering from mastitis, the appearance of PrP(C in milk implies the possibility that milk of TSE-infected animals serves as source for PrP(Sc.

  1. Associations between milk protein polymorphisms and milk production traits.

    NARCIS (Netherlands)

    Bovenhuis, H.; Arendonk, van J.A.M.; Korver, S.

    1992-01-01

    Associations between milk protein genotypes and milk production traits were estimated from 6803 first lactation records. Exact tests of associated hypotheses and unbiased estimates of genotype effects were from an animal model. Milk protein genotype effects were estimated using a model in which each

  2. The Optimization of Milk Protein Using Different Breeding Systems

    Directory of Open Access Journals (Sweden)

    Ramona Iancu

    2011-10-01

    Full Text Available The purpose of this study is to increase the intensive production systems in dairy goat flocks necessity specifications on feeding strategies and housing structures to optimize milk production and animal welfare and to control the impact of animal husbandry on the environment. Milk serves as the most excellent sources of protein with rich quality protein content. It doesn’t contain a large quantity of proteins, but those are containing all the essential amino acids that the body requires. The nutritional and processing properties and there by the market value of milk, largely depends on its protein content.

  3. Metabolic attributes, yield and stability of milk in Jersey cows fed diets containing sodium citrate and sodium bicarbonate

    OpenAIRE

    2013-01-01

    The objective of this work was to evaluate the inclusion of sodium citrate and sodium bicarbonate in the diet of lactating Jersey cows, and its effects on the metabolic attributes, productivity and stability of milk. We evaluated urinary pH, levels of glucose and urea in blood, body weight, body condition score, milk yield, milk stability (ethanol test), and milk physicochemical properties of 17 cows fed diets containing sodium citrate (100 g per cow per day), sodium bicarbonate (40 g per cow...

  4. Milk cortisol concentration in automatic milking systems compared with auto-tandem milking parlors.

    Science.gov (United States)

    Gygax, L; Neuffer, I; Kaufmann, C; Hauser, R; Wechsler, B

    2006-09-01

    Milk cortisol concentration was determined under routine management conditions on 4 farms with an auto-tandem milking parlor and 8 farms with 1 of 2 automatic milking systems (AMS). One of the AMS was a partially forced (AMSp) system, and the other was a free cow traffic (AMSf) system. Milk samples were collected for all the cows on a given farm (20 to 54 cows) for at least 1 d. Behavioral observations were made during the milking process for a subset of 16 to 20 cows per farm. Milk cortisol concentration was evaluated by milking system, time of day, behavior during milking, daily milk yield, and somatic cell count using linear mixed-effects models. Milk cortisol did not differ between systems (AMSp: 1.15 +/- 0.07; AMSf: 1.02 +/- 0.12; auto-tandem parlor: 1.01 +/- 0.16 nmol/L). Cortisol concentrations were lower in evening than in morning milkings (1.01 +/- 0.12 vs. 1.24 +/- 0.13 nmol/L). The daily periodicity of cortisol concentration was characterized by an early morni