WorldWideScience

Sample records for chymosin

  1. Camel and bovine chymosin

    DEFF Research Database (Denmark)

    Langholm Jensen, Jesper; Mølgaard, Anne; Navarro Poulsen, Jens Christian;

    2013-01-01

    Bovine and camel chymosin are aspartic peptidases that are used industrially in cheese production. They cleave the Phe105-Met106 bond of the milk protein κ-casein, releasing its predominantly negatively charged C-terminus, which leads to the separation of the milk into curds and whey. Despite...... having 85% sequence identity, camel chymosin shows a 70% higher milk-clotting activity than bovine chymosin towards bovine milk. The activities, structures, thermal stabilities and glycosylation patterns of bovine and camel chymosin obtained by fermentation in Aspergillus niger have been examined...... interactions arising from variation in the surface charges and the greater malleability both in domain movements and substrate binding contribute to the better milk-clotting activity of camel chymosin towards bovine milk....

  2. Cloning and Expression of Yak Active Chymosin in Pichia pastoris.

    Science.gov (United States)

    Luo, Fan; Jiang, Wei Hua; Yang, Yuan Xiao; Li, Jiang; Jiang, Ming Feng

    2016-09-01

    Rennet, a complex of enzymes found in the stomachs of ruminants, is an important component for cheese production. In our study, we described that yak chymosin gene recombinant Pichia pastoris strain could serve as a novel source for rennet production. Yaks total RNA was extracted from the abomasum of an unweaned yak. The yak preprochymosin, prochymosin, and chymosin genes from total RNA were isolated using gene specific primers based on cattle chymosin gene sequence respectively and analyzed their expression pattern byreal time-polymerase chain reaction. The result showed that the chymosin gene expression level of the sucking yaks was 11.45 times higher than one of adult yaks and yak chymosin belongs to Bovidae family in phylogenetic analysis. To express each, the preprochymosin, prochymosin, and chymosin genes were ligated into the expression vector pPICZαA, respectively, and were expressed in Pichia pastoris X33. The results showed that all the recombinant clones of P. pastoris containing the preprochymosin, prochymosin or chymosin genes could produce the active form of recombinant chymosin into the culture supernatant. Heterologous expressed prochymosin (14.55 Soxhlet unit/mL) had the highest enzyme activity of the three expressed chymosin enzymes. Therefore, we suggest that the yak chymosin gene recombinant Pichia pastoris strain could provide an alternative source of rennet production. PMID:27004812

  3. Structure and Function of Bovine and Camel Chymosin

    DEFF Research Database (Denmark)

    Jensen, Jesper Langholm

    complexes of bovine chymosin, human pepsin, and endothiapepsin with the inhibitor pepstatin were examined to explain pepstatin’s lower affinity towards bovine chymosin. Human pepsin has a loop insert and a more hydrophobic binding cleft leading to a larger interaction surface with the hydrophobic pepstatin...

  4. Camel and bovine chymosin: the relationship between their structures and cheese-making properties

    International Nuclear Information System (INIS)

    Analysis of the crystal structures of the two milk-clotting enzymes bovine and camel chymosin has revealed that the better milk-clotting activity towards bovine milk of camel chymosin compared with bovine chymosin is related to variations in their surface charges and their substrate-binding clefts. Bovine and camel chymosin are aspartic peptidases that are used industrially in cheese production. They cleave the Phe105-Met106 bond of the milk protein κ-casein, releasing its predominantly negatively charged C-terminus, which leads to the separation of the milk into curds and whey. Despite having 85% sequence identity, camel chymosin shows a 70% higher milk-clotting activity than bovine chymosin towards bovine milk. The activities, structures, thermal stabilities and glycosylation patterns of bovine and camel chymosin obtained by fermentation in Aspergillus niger have been examined. Different variants of the enzymes were isolated by hydrophobic interaction chromatography and showed variations in their glycosylation, N-terminal sequences and activities. Glycosylation at Asn291 and the loss of the first three residues of camel chymosin significantly decreased its activity. Thermal differential scanning calorimetry revealed a slightly higher thermal stability of camel chymosin compared with bovine chymosin. The crystal structure of a doubly glycosylated variant of camel chymosin was determined at a resolution of 1.6 Å and the crystal structure of unglycosylated bovine chymosin was redetermined at a slightly higher resolution (1.8 Å) than previously determined structures. Camel and bovine chymosin share the same overall fold, except for the antiparallel central β-sheet that connects the N-terminal and C-terminal domains. In bovine chymosin the N-terminus forms one of the strands which is lacking in camel chymosin. This difference leads to an increase in the flexibility of the relative orientation of the two domains in the camel enzyme. Variations in the amino acids

  5. Camel and bovine chymosin: the relationship between their structures and cheese-making properties

    Energy Technology Data Exchange (ETDEWEB)

    Langholm Jensen, Jesper [University of Copenhagen, (Denmark); Chr. Hansen A/S, Bøge Allé 10-12, DK-2970 Hørsholm (Denmark); Mølgaard, Anne; Navarro Poulsen, Jens-Christian [University of Copenhagen, (Denmark); Harboe, Marianne Kirsten [Chr. Hansen A/S, Bøge Allé 10-12, DK-2970 Hørsholm (Denmark); Simonsen, Jens Bæk [University of Copenhagen, (Denmark); Lorentzen, Andrea Maria; Hjernø, Karin [University of Southern Denmark, (Denmark); Brink, Johannes M. van den; Qvist, Karsten Bruun [Chr. Hansen A/S, Bøge Allé 10-12, DK-2970 Hørsholm (Denmark); Larsen, Sine, E-mail: sine@chem.ku.dk [University of Copenhagen, (Denmark)

    2013-05-01

    Analysis of the crystal structures of the two milk-clotting enzymes bovine and camel chymosin has revealed that the better milk-clotting activity towards bovine milk of camel chymosin compared with bovine chymosin is related to variations in their surface charges and their substrate-binding clefts. Bovine and camel chymosin are aspartic peptidases that are used industrially in cheese production. They cleave the Phe105-Met106 bond of the milk protein κ-casein, releasing its predominantly negatively charged C-terminus, which leads to the separation of the milk into curds and whey. Despite having 85% sequence identity, camel chymosin shows a 70% higher milk-clotting activity than bovine chymosin towards bovine milk. The activities, structures, thermal stabilities and glycosylation patterns of bovine and camel chymosin obtained by fermentation in Aspergillus niger have been examined. Different variants of the enzymes were isolated by hydrophobic interaction chromatography and showed variations in their glycosylation, N-terminal sequences and activities. Glycosylation at Asn291 and the loss of the first three residues of camel chymosin significantly decreased its activity. Thermal differential scanning calorimetry revealed a slightly higher thermal stability of camel chymosin compared with bovine chymosin. The crystal structure of a doubly glycosylated variant of camel chymosin was determined at a resolution of 1.6 Å and the crystal structure of unglycosylated bovine chymosin was redetermined at a slightly higher resolution (1.8 Å) than previously determined structures. Camel and bovine chymosin share the same overall fold, except for the antiparallel central β-sheet that connects the N-terminal and C-terminal domains. In bovine chymosin the N-terminus forms one of the strands which is lacking in camel chymosin. This difference leads to an increase in the flexibility of the relative orientation of the two domains in the camel enzyme. Variations in the amino acids

  6. Influence of pH on retention of camel chymosin in curd

    DEFF Research Database (Denmark)

    Børsting, Mette Winther; Qvist, Karsten B.; Ardö, Ylva Margareta

    2014-01-01

    Retained coagulant in cheese initiates casein breakdown and influences cheese structure and flavour formation. This study investigated the influence of milk pH on retention of camel chymosin in curd and compared it with bovine chymosin. Milk at five different pH levels was coagulated with same...... coagulant activity of each chymosin and centrifuged. Chymosin activity in whey was determined using the synthetic peptide Pro-Thr-Glu-Phe-(NO2-Phe)-Arg-Leu as substrate and HPLC analysis of the resulting product. Camel chymosin had 2.7 times lower activity in milk than bovine chymosin at the same...... coagulation activity. The retention of camel chymosin in curd was rather constant at ∼20% between pH 6.65 and 6.00, while it increased almost linear from 2 to 21% for bovine chymosin. The lower pH dependence for retention of camel chymosin than of bovine chymosin may be explained by a lower negative charge of...

  7. Effects of Adding Chymosin to Milk on Calcium Homeostasis

    DEFF Research Database (Denmark)

    Møller, Ulla Kristine; Jensen, Lars Thorbjørn; Mosekilde, Leif;

    2014-01-01

    Calcium intake and absorption is important for bone health. In a randomized double-blind cross-over trial, we investigated effects of adding chymosin to milk on the intestinal calcium absorption as measured by renal calcium excretion and indices of calcium homeostasis. The primary outcome of the...

  8. 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 amber to dark brown liquid preparations or white to tan powders. (2) Chymosin preparation is...

  9. Mathematical modelling of the formation of rennet-induced gels by plant coagulants and chymosin.

    Science.gov (United States)

    Esteve, C L; Lucey, J A; Pires, E M

    2001-08-01

    Rheological properties of reconstituted skim milk coagulated with plant coagulants Cynara cardunculus L., Cynara humilis L. and chymosin was monitored by dynamic low amplitude oscillation. There are no published reports on the modelling of the gelation behaviour of milk by plant coagulants. Three mathematical models, Scott Blair. Douillard and Carlson, were fitted to the storage modulus (G') as function of time curves. For all coagulants. Scott Blair model was the most efficient in modelling the gelation process, and gave both the smallest residuals and standard error of residuals, Se (P gels with slightly higher G' values than chymosin, but after longer incubation times chymosin gels had higher G' values. It was concluded that the Scott Blair model was the best equation to follow the gelation of milk induced by both plant coagulants as well as chymosin. Modelling is an important and useful method for comparing the gelation process in gels formed by different types of coagulants. PMID:11694051

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

    DEFF Research Database (Denmark)

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

    2016-01-01

    The effects of temperature, pH, concentration of camel chymosin and addition of CaCl2 on the hydrolysis of κ-casein (κ-CN) and the coagulation kinetics of camel milk were investigated. The rate of κ-CN hydrolysis was higher at 40 °C than at 30 °C and with increasing addition of chymosin and decre...

  11. Development of a Radioimmunoassay for Bovine Chymosin B

    Directory of Open Access Journals (Sweden)

    Borceux, JP.

    2007-01-01

    Full Text Available The present study was conducted to develop and validate a specific radioimmunoassay system for measurement of bovine chymosin B (bChyB concentrations in plasma samples. Bovine ChyB was used for immunization of rabbits and as standard and tracer. Chymosin B concentrations were measured in plasma samples from two groups of calves (Group 1: calves sampled from birth to 24 hours; Group 2: calves sampled from Day 1 to 21 after birth and from one cow during the peri-partum period. Detection limit of the assay was 9.0 ng/ml. Recovery was higher than 89.3%. Repeatability and reproducibility ranged from 1.52% to 5.23% and from 1.52% to 12.57% respectively. No cross-reaction was found with pepsinogen A from bovine, porcine or human origins. In Group 1, bChyB concentrations increased from 47.3 ± 45.1 ng/ml (5 min after birth to 325.5 ± 161.2 ng/ml (12 hours after birth, then no significant change was observed till 24 hours after birth (293.0 ± 161.5 ng/ml. In Group 2, concentrations decreased from Day 1 (455.3 ± 191.1 ng/ml to Day 21 (117.9 ± 85.1 ng/ml. In adult cow, mean concentration was 136.0 ± 32.3 ng/ml. In conclusion, bChyB is able to cross the stomach basal membrane and to reach the blood circulation at detectable levels in both young calves and adult cows.

  12. Bovine Chymosin: A Computational Study of Recognition and Binding of Bovine κ-Casein

    DEFF Research Database (Denmark)

    Palmer, David S.; Christensen, Anders Uhrenholt; Sørensen, Jesper; Celik, Leyla; Qvist, Karsten Bruun; Schiøtt, Hanne Birgit

    2010-01-01

    Bovine chymosin is an aspartic protease that selectively cleaves the milk protein κ-casein. The enzyme is widely used to promote milk clotting in cheese manufacturing. We have developed models of residues 97-112 of bovine κ-casein complexed with bovine chymosin, using ligand docking, conformational...... search algorithms, and molecular dynamics simulations. In agreement with limited experimental evidence, the model suggests that the substrate binds in an extended conformation with charged residues on either side of the scissile bond playing an important role in stabilizing the binding pose. Lys111 and...... Lys112 are observed to bind to the N-terminal domain of chymosin displacing a conserved water molecule. A cluster of histidine and proline residues (His98-Pro99-His100-Pro101-His102) in κ-casein binds to the C-terminal domain of the protein, where a neighboring conserved arginine residue (Arg97) is...

  13. Factors influencing chymosin-induced gelation of milk from individual dairy cows

    DEFF Research Database (Denmark)

    Gustavsson, F.; Glantz, M; Buitenhuis, Albert Johannes; Lindmark-Månsson, H; Stålhammar, Hans; Andrén, A; Paulsson, M.

    2014-01-01

    Optimisation of cheese yield is crucial for cheese production; a previous study showed large variations in chymosin-induced coagulation in milk from the second most common Swedish dairy breed, Swedish Red. In the present study, the effect of gross composition, protein composition, total and ionic...... was, theoretically, four times larger than the amount of calcium that is normally added in cheese processing......Optimisation of cheese yield is crucial for cheese production; a previous study showed large variations in chymosin-induced coagulation in milk from the second most common Swedish dairy breed, Swedish Red. In the present study, the effect of gross composition, protein composition, total and ionic...

  14. Production in stirred-tank bioreactor of recombinant bovine chymosin B by a high-level expression transformant clone of Pichia pastoris.

    Science.gov (United States)

    Noseda, Diego Gabriel; Recúpero, Matías; Blasco, Martín; Bozzo, Joaquín; Galvagno, Miguel Ángel

    2016-07-01

    An intense screening of Pichia pastoris clones transformed with the gene of bovine chymosin under methanol-inducible AOX1 promoter was performed, obtaining a transformant clone with a higher milk-clotting activity value in comparison with our previous studies. The scaling of recombinant-chymosin production was carried out by a fed-batch strategy in a stirred-tank bioreactor using biodiesel-byproduct crude glycerol as the carbon source and pure methanol for the induction of chymosin expression, achieving a biomass concentration of 158 g DCW/L and a maximum coagulant activity of 192 IMCU/ml after 120 h of methanol induction. Recombinant bovine chymosin was purified from bioreactor-fermentation culture by a procedure including anion-exchange chromatography which allowed obtaining heterologous chymosin with high level of purity and activity; suggesting that this downstream step could be scaled up in a successful manner for chymosin purification. Thermoestability assay permitted to establish that unformulated recombinant chymosin could be stored at 5 °C without decrease of enzyme activity throughout at least 120 days. Finally, reiterative methanol-inductions of recombinant chymosin expression in bioreactor demonstrated that the reutilization of cell biomass overcame the low enzyme productivity usually reached by P. pastoris system. PMID:27033608

  15. Purify of MJ229 Chymosin%MJ229凝乳酶的纯化

    Institute of Scientific and Technical Information of China (English)

    程巧玲

    2011-01-01

    Chymosin is one of the key enzymes during the production of cheese. With the development of cheese industry, chymosin made by traditional method is not sufficient for its production, so the researchers are looking for the new sources of cbymosin. MJ229 can produce chymosin, that was isolated from glutinous rice wine which was a traditional food in south of China. The enzyme liquor of MJ229 solid - state fermentation was concentrated through hollow fiber ultrafiltration membrane with aperture 60kDa and 6kDa during this experiment. The volume was concentrated 15. 6 times.The enzyme was purified 2. 15 times and the yield radio was 82. 6%. The concentration was purified by Sephadex G 100. The milk -clotting activity was 2200. 0U/mg after purification and it was confirmed by SDS - PAGE pattern that showed the chymosin was nearly purified with a molecular mass of 35.0kDa.%凝乳酶是干酪生产中的关键性酶,随着世界干酪工业的不断发展,传统来源的凝乳酶已远不能满足生产需要,各国研究者不断地寻找新的来源.MJ229是从我国传统食品江米酒酒醪中筛选得到的一株凝乳酶高产菌株.本实验利用截留分子量为60kDa和6kDa的中空纤维超滤膜对MJ229固态发酵物中凝乳酶的浸提液进行浓缩,浸提液体积被浓缩了15.6倍,凝乳酶纯化倍数达2.15倍,活力回收率为82.6%.进一步通过SephadexG-100纯化,得到电泳纯的凝乳酶,活力为2200.0U/mg,同时测得其分子量为35kDa.

  16. Rheological properties of milk gels made with coagulants of plant origin and chymosin

    OpenAIRE

    Esteves, Cristina L. C.; Lucey, John A.; Pires, Euclides M. V.

    2002-01-01

    The rheological properties of milk gels made using coagulants obtained from the plants Cynara cardunculus L. and Cynara humilis L. were compared with those of fermentation-produced chymosin, using dynamic low amplitude oscillation as well as large strain (yield) testing. Gelation experiments were performed at 32°C using skim milk powder that had been reconstituted for 2 or 16 h at 32°C. The storage modulus (G'), loss tangent (tan[delta]) at low frequency (0.002 Hz) and yield stress were highe...

  17. Functional Properties of Pea (Pisum sativum, L. Protein Isolates Modified with Chymosin

    Directory of Open Access Journals (Sweden)

    Nikola Ristić

    2011-11-01

    Full Text Available In this paper, the effects of limited hydrolysis on functional properties, as well as on protein composition of laboratory-prepared pea protein isolates, were investigated. Pea protein isolates were hydrolyzed for either 15, 30 and 60 min with recombined chymosin (Maxiren. The effect of enzymatic action on solubility, emulsifying and foaming properties at different pH values (3.0; 5.0; 7.0 and 8.0 was monitored. Chymosin can be a very useful agent for improvement of functional properties of isolates. Action of this enzyme caused a low degree of hydrolysis (3.9–4.7%, but improved significantly functional properties of pea protein isolates (PPI, especially at lower pH values (3.0–5.0. At these pH values all hydrolysates had better solubility, emulsifying activity and foaming stability, while longer-treated samples (60 min formed more stable emulsions at higher pH values (7.0, 8.0 than initial isolates. Also, regardless of pH value, all hydrolysates showed improved foaming ability. A moderate positive correlation between solubility and emulsifying activity index (EAI (0.74 and negative correlation between solubility and foam stability (−0.60 as well as between foam stability (FS and EAI (−0.77 were observed. Detected enhancement in functional properties was a result of partial hydrolysis of insoluble protein complexes.

  18. Functional properties of pea (Pisum sativum, L.) protein isolates modified with chymosin.

    Science.gov (United States)

    Barać, Miroljub; Cabrilo, Slavica; Pešić, Mirjana; Stanojević, Slađana; Pavlićević, Milica; Maćej, Ognjen; Ristić, Nikola

    2011-01-01

    In this paper, the effects of limited hydrolysis on functional properties, as well as on protein composition of laboratory-prepared pea protein isolates, were investigated. Pea protein isolates were hydrolyzed for either 15, 30 and 60 min with recombined chymosin (Maxiren). The effect of enzymatic action on solubility, emulsifying and foaming properties at different pH values (3.0; 5.0; 7.0 and 8.0) was monitored. Chymosin can be a very useful agent for improvement of functional properties of isolates. Action of this enzyme caused a low degree of hydrolysis (3.9-4.7%), but improved significantly functional properties of pea protein isolates (PPI), especially at lower pH values (3.0-5.0). At these pH values all hydrolysates had better solubility, emulsifying activity and foaming stability, while longer-treated samples (60 min) formed more stable emulsions at higher pH values (7.0, 8.0) than initial isolates. Also, regardless of pH value, all hydrolysates showed improved foaming ability. A moderate positive correlation between solubility and emulsifying activity index (EAI) (0.74) and negative correlation between solubility and foam stability (-0.60) as well as between foam stability (FS) and EAI (-0.77) were observed. Detected enhancement in functional properties was a result of partial hydrolysis of insoluble protein complexes. PMID:22272078

  19. Solvent Binding Analysis and Computational Alanine Scanning of the Bovine Chymosin-Bovine κ-Casein Complex Using Molecular Integral Equation Theory.

    Science.gov (United States)

    Palmer, David S; Sørensen, Jesper; Schiøtt, Birgit; Fedorov, Maxim V

    2013-12-10

    We demonstrate that the relative binding thermodynamics of single-point mutants of a model protein-peptide complex (the bovine chymosin-bovine κ-casein complex) can be calculated accurately and efficiently using molecular integral equation theory. The results are shown to be in good overall agreement with those obtained using implicit continuum solvation models. Unlike the implicit continuum models, however, molecular integral equation theory provides useful information about the distribution of solvent density. We find that experimentally observed water-binding sites on the surface of bovine chymosin can be identified quickly and accurately from the density distribution functions computed by molecular integral equation theory. The bovine chymosin-bovine κ-casein complex is of industrial interest because bovine chymosin is widely used to cleave bovine κ-casein and to initiate milk clotting in the manufacturing of processed dairy products. The results are interpreted in light of the recent discovery that camel chymosin is a more efficient clotting agent than bovine chymosin for bovine milk. PMID:26592300

  20. Proteolytic Activity in Reduced-Fat Cheddar Cheese Made with Lactic Acid Bacteria and Camel Chymosin

    DEFF Research Database (Denmark)

    Børsting, Mette Winther

    need of an extended ripening period to reach a similar cheese structure as in cheeses produced with BC. The aim of this project was to compensate for the lower proteolytic activity in cheese produced with CC compared to BC. Selection of dairy lactic acid bacteria (LAB) for cheese production with high...... ability to influence proteolysis and structure during cheese ripening. In an attempt to improve the screening methods and contribute to the development of a new classification system of Latcococcus lactic strains, the peptide profile formed by selected strains after growth in milk was analyzed and...... culture mediated an increase in the total amount of amino acids as well as a shorter structure. A model system, used to study the retention of chymosin in a curd, showed that the retention of CC was less dependent on pH compared to BC, and the retention of CC was higher than BC in the pH interval 6...

  1. Use of grape pomaces to produce biomass of aKomagataella pastoris strain expressing a bovine chymosin activity

    OpenAIRE

    Kingston, Diego; Novelli, Guido F; Cerrutti, Patricia; Recupero, Matias N; Blasco, Martin; Galvagno, Miguel A

    2014-01-01

    The use of agroindustrial wastes not only decreases bioprocesses and disposal costs but also contributes to the upgrading of the residues. An active recombinant methanol-inducible bovine chymosin has been expressed in our laboratory in the yeastKomagataella pastoris, and grape pomace extracts (GRE) were proposed as a convenient C-energy source for the biomass production of the genetically engineered strain. Carbon and nitrogen sources, growth factors, and initial pH conditions were selected b...

  2. Use of grape pomaces to produce biomass of aKomagataella pastoris strain expressing a bovine chymosin activity.

    Science.gov (United States)

    Kingston, Diego; Novelli, Guido F; Cerrutti, Patricia; Recupero, Matias N; Blasco, Martin; Galvagno, Miguel A

    2014-11-01

    The use of agroindustrial wastes not only decreases bioprocesses and disposal costs but also contributes to the upgrading of the residues. An active recombinant methanol-inducible bovine chymosin has been expressed in our laboratory in the yeastKomagataella pastoris, and grape pomace extracts (GRE) were proposed as a convenient C-energy source for the biomass production of the genetically engineered strain. Carbon and nitrogen sources, growth factors, and initial pH conditions were selected by classical methodology; thereafter, growth conditions optimization was performed using statistical designed experiments (DoEs). In the presence of (in g·L(-1)) 67.0 monosaccharides (glucose and fructose) from GRE, 5.0 (NH4)2SO4, and 10.0 sugar cane molasses (CMz), a yield of 20.0 g·L(-1) cell dry weight (CDW) was obtained aerobically after 60 h incubation at 28°C and pH 4.0. Applying a fed-batch strategy with methanol:sorbitol as the enzyme inducers, a chymosin production of 8.53 International Milk Clotting Units (IMCU) per mg protein was obtained in the supernatant. The results presented show that through a statistical design, a simple, cheap, and easy to prepare culture medium could be developed using two agroindustrial derivatives (GRE and CMz) to obtain a higher value added product. PMID:25493192

  3. Effect of camel chymosin on the texture, functionality, and sensory properties of low-moisture, part-skim Mozzarella cheese.

    Science.gov (United States)

    Moynihan, A C; Govindasamy-Lucey, S; Jaeggi, J J; Johnson, M E; Lucey, J A; McSweeney, P L H

    2014-01-01

    The objective of this study was to compare the effect of coagulant (bovine calf chymosin, BCC, or camel chymosin, CC), on the functional and sensory properties and performance shelf-life of low-moisture, part-skim (LMPS) Mozzarella. Both chymosins were used at 2 levels [0.05 and 0.037 international milk clotting units (IMCU)/mL], and clotting temperature was varied to achieve similar gelation times for each treatment (as this also affects cheese properties). Functionality was assessed at various cheese ages using dynamic low-amplitude oscillatory rheology and performance of baked cheese on pizza. Cheese composition was not significantly different between treatments. The level of total calcium or insoluble (INSOL) calcium did not differ significantly among the cheeses initially or during ripening. Proteolysis in cheese made with BCC was higher than in cheeses made with CC. At 84 d of ripening, maximum loss tangent values were not significantly different in the cheeses, suggesting that these cheeses had similar melt characteristics. After 14 d of cheese ripening, the crossover temperature (loss tangent = 1 or melting temperature) was higher when CC was used as coagulant. This was due to lower proteolysis in the CC cheeses compared with those made with BCC because the pH and INSOL calcium levels were similar in all cheeses. Cheeses made with CC maintained higher hardness values over 84 d of ripening compared with BCC and maintained higher sensory firmness values and adhesiveness of mass scores during ripening. When melted on pizzas, cheese made with CC had lower blister quantity and the cheeses were firmer and chewier. Because the 2 types of cheeses had similar moisture contents, pH values, and INSOL Ca levels, differences in proteolysis were responsible for the firmer and chewier texture of CC cheeses. When cheese performance on baked pizza was analyzed, properties such as blister quantity, strand thickness, hardness, and chewiness were maintained for a longer

  4. Extraction of chymosin produced by solid state fermentation of mucor MJ229%毛霉MJ229固态发酵凝乳酶提取工艺研究

    Institute of Scientific and Technical Information of China (English)

    王艳萍; 张殿伟; 程巧玲; 白小佳

    2011-01-01

    Chymosin is a key enzyme in cheese production which causes milk curd.It plays a very important role in the formation of texture and flavor in cheese.With the development of cheese industry, chymosin made by traditional method is not sufficient for its production, so the researchers are looking for the new sources of chymosin.MJ229 can produce chymosin, that was isolated from glutinous rice wine which was a traditional food in south of China.This paper studied the extraction process of chymosin from the Mucor MJ229 solid state fermentation broth, using single factor analysis of the extraction time, salt concentration, extraction temperature, extraction times which affect extraction of chymosin.The results showed that the optimized extraction conditions were: the temperature is 40℃, NaCl concentration is 0.3 mol/L, extracted 20min for 3 times.%凝乳酶是干酪生产中的关键性酶.它对干酪的质构形成及特有风味的形成有非常重要的作用.随着干酪工业的不断发展,传统来源的凝乳酶已远不能满足生产需要,各国研究者不断地寻找新的来源.霉菌MJ229是从我国传统食品江米酒酒醪中筛选得到的一株凝乳酶高产菌株.本论文对霉菌MJ229固态发酵物中凝乳酶的提取工艺进行了研究,分别研究了提取时间、食盐浓度、提取温度、次数对固态发酵液中凝乳酶提取效果的影响.结果表明,霉菌MJ229固态发酵中凝乳酶在温度40℃条件下,用0.3mol/L的NaCl溶液提取20min,提取3次的效果为最好.

  5. Rapid quantification of casein in skim milk using Fourier transform infrared spectroscopy, enzymatic perturbation, and multiway partial least squares regression: Monitoring chymosin at work.

    Science.gov (United States)

    Baum, A; Hansen, P W; Nørgaard, L; Sørensen, John; Mikkelsen, J D

    2016-08-01

    In this study, we introduce enzymatic perturbation combined with Fourier transform infrared (FTIR) spectroscopy as a concept for quantifying casein in subcritical heated skim milk using chemometric multiway analysis. Chymosin is a protease that cleaves specifically caseins. As a result of hydrolysis, all casein proteins clot to form a creamy precipitate, and whey proteins remain in the supernatant. We monitored the cheese-clotting reaction in real time using FTIR and analyzed the resulting evolution profiles to establish calibration models using parallel factor analysis and multiway partial least squares regression. Because we observed casein-specific kinetic changes, the retrieved models were independent of the chemical background matrix and were therefore robust against possible covariance effects. We tested the robustness of the models by spiking the milk solutions with whey, calcium, and cream. This method can be used at different stages in the dairy production chain to ensure the quality of the delivered milk. In particular, the cheese-making industry can benefit from such methods to optimize production control. PMID:27265175

  6. A Study on Relationships between the Activities of Repsin,Chymosin, Lactase and Their mRNA Relative Expressional Volumes and Development of the Stomach and Intestines of 7-35 Day Old Lambs%7~35日龄羔羊胃肠胃蛋白酶、凝乳酶、乳糖酶活性与其 mRNA 相对表达量和胃肠发育的关系研究

    Institute of Scientific and Technical Information of China (English)

    牛越峰; 雒秋江; 陈勇; 李凤鸣; 张慧玲

    2014-01-01

    Fifty six head of Small-tail Han lamb with body weight of (3 360±338)g were selected in ex-periment and were divided randomly into 14 groups (n =4,in each group).From 4 day old the lambs were fed with milk powder substitute (MPS)(n =28)or fish meal substitute (FMS)(n =28)respectively,and from 21 day old,8 of lamb fed with MPS or FMS were turned to be fed with starter ration respectively. Each group of lamb at 7,14,21,28 and 35 day old was sacrificed to take the abomasum and duodenum tis-sue,measuring the activities of the pepsin,chymosin and lactase and the corresponding relative expression of mRNA,for studying the development of 3 digestive enzymes of lamb fed with MPS,FMS and starter ra-tion respectively.The result showed that in abomasum or duodenum tissue of newborn lamb the activities of the chymosin and lactase were decreased with the age of lamb by 1.3 U/g (r 2 = 0.92,P 0.05)respectively,but the pepsin activity was weakly related with the age.The relationships be-tween the activities of the pepsin,chymosin and lactase and thier corresponding relative expression of mR-NA was poor,the mRNA expressions of the pepsin and chymosin were fluctuated by high-low-high with the age,however the activity of lactose was not significantly changed with the age of lamb.When FMS was fed,the activities of pepsin,and chymosinwere decreased,the weight of abomasum was (36.0 ±3.0)g at 7 day old of lamb,and was (38.3±5.4)g at 35 day old,suggesting a growth retardation.Turning to starter ration at 21 days of lamb fed priviously with MPS did not significantly affect the activities of the pepsin, chymosin and lactase.But the abomasum and duodenum and daily weight gains of the lambs reduced.Fur-thermore,the activities of pepsin,chymosin and lactase in the milk substitutes,which were fed priviously to the lambs,tended to declining which affected obviously abomasum and duodenum and daily weight gains of the lambs.It is concluded that the pepsin activity is weakly related with the age

  7. Cheese from Ultrafiltered Milk : whey proteins and chymosin activity

    NARCIS (Netherlands)

    Buijsse, C.

    1999-01-01

    The manufacture of (semi-)hard cheese from ultrafiltered milk (UF-cheese) enables the partial incorporation of whey proteins in the cheese, thereby increasing its yield. The transfer of whey proteins in curd from (UF-)milk was studied in relation to the degree of ultrafiltration of the milk and the

  8. Cheese from Ultrafiltered Milk : whey proteins and chymosin activity

    OpenAIRE

    Buijsse, C.

    1999-01-01

    The manufacture of (semi-)hard cheese from ultrafiltered milk (UF-cheese) enables the partial incorporation of whey proteins in the cheese, thereby increasing its yield. The transfer of whey proteins in curd from (UF-)milk was studied in relation to the degree of ultrafiltration of the milk and the degree of syneresis of the curd. In UF-cheese manufacture (from 5x concentrated UF-retentates, concentrated further by syneresis) approximately one-third of the whey protein fraction was enclosed.D...

  9. The adsorption of lysozyme and chymosin onto emulsion droplets and their association with caseins

    OpenAIRE

    Roos, de, S.A.

    1999-01-01

    The proteolytic action of proteases present in cheese plays a major role in the ripening of cheese. These proteases originate from the rennet, the starter cultures and from the milk itself. The proteolysis in cheese results in the degradation of the casein proteins into smaller peptides and free amino acids, which act as flavour precursors. The ripening of cheese under conditioned storage is time consuming and costly. Addition of specific enzymes to the cheese milk is one of several options t...

  10. Efeito da hidrólise enzimática sobre propriedades funcionais de caseína bovina coagulada pela ação da quimosina Effect of enzimatic hydrolysis on functional properties of bovine casein coagulated by the action of chymosin

    Directory of Open Access Journals (Sweden)

    Janesca Alban Roman

    2005-09-01

    Full Text Available Este trabalho teve como objetivo verificar a influência do grau de hidrólise sobre as propriedades funcionais hidrofílicas (capacidade de absorção espontânea de água-CAA, capacidade de retenção de água-CRA e solubilidade da proteína-SP e de superfície (capacidade de formação e estabilização de espumas e de emulsões da caseína bovina obtida por coagulação enzimática. Os graus de hidrólise (GH estudados foram: 5,7; 12,8; 20,1 e 35,8%. Observou-se que quanto maior o GH maior a SP e menor a CRA dos hidrolisados. A hidrólise enzimática melhorou a capacidade de formação de espuma, pois o coágulo de caseína (COC não formou espuma nas condições estudadas. A melhor capacidade de formação de espuma foi conseguida com o GH 12,8% e a maior estabilidade com GH 5,7%. Os hidrolisados, com GH 12,8; 20,1 e 35,8% não formaram emulsão. Não houve diferenças significativas entre o GH 5,7% e o COC quanto à formação de emulsão, mas a estabilidade da emulsão do hidrolisado de menor grau de hidrólise foi significativamente superior ao coágulo de caseína.The objective of the present work was to study the influence of degree of hydrolysis (DH on the hydrophilic and surface functional properties of a bovine casein obtained by enzymatic coagulation (COC. The degrees of hydrolysis produced were 5.7, 12.8, 20.1 and 35.8%. It was observed that the higher the DH, the higher the protein solubility and the lower the water retention capacity (WRC of the hydrolysates. The best foaming capacity was obtained with 12.8% DH and best foam stability with 5.7% DH. The hydrolysate with 5.7% DH showed the same emulsifying capacity as the coagulated casein, however emulsion stability was superior for the 5.7% hydrolysate than for COC. The hydrolysates with higher DH (12.8, 20.1 and 35.8% did not form emulsion.

  11. Efeito da hidrólise enzimática sobre propriedades funcionais de caseína bovina coagulada pela ação da quimosina Effect of enzimatic hydrolysis on functional properties of bovine casein coagulated by the action of chymosin

    OpenAIRE

    Janesca Alban Roman; Valdemiro Carlos Sgarbieri

    2005-01-01

    Este trabalho teve como objetivo verificar a influência do grau de hidrólise sobre as propriedades funcionais hidrofílicas (capacidade de absorção espontânea de água-CAA, capacidade de retenção de água-CRA e solubilidade da proteína-SP) e de superfície (capacidade de formação e estabilização de espumas e de emulsões) da caseína bovina obtida por coagulação enzimática. Os graus de hidrólise (GH) estudados foram: 5,7; 12,8; 20,1 e 35,8%. Observou-se que quanto maior o GH maior a SP e menor a CR...

  12. Modification de la surface de films de caséine par l'action enzymatique de la chymosine mise en évidence par diffusion aux petits angles en incidence rasante de rayons X de taille micrométrique (μGISAXS)

    OpenAIRE

    Gebhardt, Ronald; Burghammer, Manfred; Riekel, Christian; Kulozik, Ulrich; Müller-Buschbaum, Peter

    2010-01-01

    Micro-beam grazing incidence small angle X-ray scattering (μGISAXS) scans were performed to investigate structural changes that occur after deposition of a droplet of rennin on a casein film. The subsequent diffusion of the droplet into the film led to a lateral and vertical concentration gradient of rennin. As a result of the enzyme action, the film surface became roughened and the formation of islands - evident. The altered surface morphology led to a variation in the μGISAXS pattern, more ...

  13. Impact of selected coagulants and starters on primary proteolysis and amino acid release related to bitterness and structure of reduced-fat Cheddar cheese

    DEFF Research Database (Denmark)

    Børsting, Mette Winther; Qvist, Karsten Bruun; Rasmussen, Morten; Vindeløv, Jannik; Vogensen, Finn Kvist; Ardö, Ylva Margareta

    2012-01-01

    structure. Whereas cheeses with BC had a higher amount of peptides released by chymosin, e. g. the bitter peptide beta-casein (f193-209) or by starter proteases from the chymosin-produced peptide alpha(s1)-CN (f1-23). BC cheeses were also judged to be softer by the sensory panel. Cheeses containing the OLb......-week ripening period for the composition of casein, peptides, free amino acids, rheological properties and for sensory properties at end of ripening. Cheeses with CC, showed less extensive primary proteolysis, lower levels of bitterness and higher stress at fracture, which correlates to a harder...

  14. Characterization of enzymatically induced aggregation of casein micelles in natural concentration by in situ static light scattering and ultra low shear viscosimetry

    DEFF Research Database (Denmark)

    Lehner, D.; Worning, Peder; G, Fritz; L, Ogendal; R, Bauer; Glatter, O.

    1999-01-01

    The aggregation of casein micelles in undiluted skim milk after the addition of chymosin was studied bystatic light scattering and ultra low shear viscometry. The static light scattering measurements were madewith two different sample thicknesses, 72 and 16 mum. The scattering data were analyzed ...

  15. Clonage et expression des prochymosines bovines A, B et B S79N chez Escherichia coli et Pichia pastoris. Etude de la mutation S79N

    OpenAIRE

    ABREU DA SILVA, Alexandra

    2004-01-01

    La chymosine, enzyme utilisée dans l´industrie fromagère pour coaguler le lait, est traditionnellement extraite à partir du quatrième estomac de veaux non sevrés. La préparation ainsi obtenue dénommée présure a été depuis un certain nombre d´années substituée par divers coagulants d´origine microbienne et de plantes car la production de cette enzyme seule n´était plus capable de répondre à la demande mondiale du fait notamment de l´augmentation de la production fromagère. La chymosine est cep...

  16. Porphyromonas gingivalis Cysteine Proteinase Inhibition by κ-Casein Peptides ▿

    OpenAIRE

    Toh, Elena C. Y.; Dashper, Stuart G.; Huq, N. Laila; Attard, Troy J.; O'Brien-Simpson, Neil M.; Chen, Yu-Yen; Cross, Keith J.; Stanton, David P.; Paolini, Rita A.; Eric C. Reynolds

    2010-01-01

    Porphyromonas gingivalis is a major pathogen associated with chronic periodontitis, an inflammatory disease of the supporting tissues of the teeth. The Arg-specific (RgpA/B) and Lys-specific (Kgp) cysteine proteinases of P. gingivalis are major virulence factors for the bacterium. In this study κ-casein(109-137) was identified in a chymosin digest of casein as an inhibiting peptide of the P. gingivalis proteinases. The peptide was synthesized and shown to inhibit proteolytic activity associat...

  17. Cloning and expression of an active aspartic proteinase from Mucor circinelloides in Pichia pastoris

    OpenAIRE

    Gama Salgado, Jose Antonio; Kangwa, Martin; Fernandez-Lahore, Marcelo

    2013-01-01

    Background Extracellular aspartic proteinase (MCAP) produced by Mucor circinelloides in solid state fermentations has been shown to possess milk clotting activity and represents a potential replacement for bovine chymosin in cheese manufacturing. Despite its prospects in the dairy industry, the molecular characteristics of this enzyme remain unknown. This work focuses on MCAP cloning and optimization of heterologous expression in Pichia pastoris, and characterization of the enzyme. Results Th...

  18. Evaluation of microbial adjuncts and their effect on the ripening of cheddar cheese

    OpenAIRE

    Ristagno, Diletta

    2013-01-01

    A bacteriocin-producing strain of Lactobacillus paracasei DPC 4715 was used as an adjunct culture in Cheddar cheese in order to control the growth of “wild” nonstarter lactic acid bacteria. No suppression of growth of the indicator strain was observed in the experimental cheese. The bacteriocin produced by Lactobacillus paracasei DPC 4715 was sensitive to chymosin and cathepsin D and it may have been cleaved by the rennet used for the cheese manufactured or by indigenous milk proteases. A ser...

  19. Mucor miehei's microbial rennin production characteristics in a fed-batch proccess

    OpenAIRE

    Sánchez Henao, C. P.; Rodríguez de Stouvenel, A.; Escobar Kousen, J. M.

    2011-01-01

    The Mucor miehei zygomycete produces an acid protease (EC:3.4.23.10) resembling calf rennet chymosin characteristics. It has been suggested that low glucose concentration levels could be why enzyme synthesis, co-mes to an end even though enzyme production is still great (Escobar and Barnett, 1993, 1995). To overcome this possible limitation, a two stage research process was designed; the relationship between protease production and sugar consumption was studied initially to determine the peri...

  20. Caseinomacropeptide self-association is dependent on whether the peptide is free or restricted in kappa-casein

    DEFF Research Database (Denmark)

    Mikkelsen, T.L.; Frokiaer, H.; Topp, C.;

    2005-01-01

    dodecyl sulfate-PAGE, N-terminal sequencing, and mass spectrometry. The hydrophobicity of CMP was studied by means of 1-anilino-naphthalene-8-sulfonic acid binding experiments. Four CMP products prepared by different methods were studied: CMP produced by enzymatic (chymosin or pepsin) hydrolysis of kappa......-casein (CN), and 2 commercial CMP products. Both commercial products and CMP-resulting from chymosin-hydrolysis of kappa-CN (at pH 6.6) had elution volumes with a MW corresponding to 35 kDA at pH 8.0 and 3.4. Caseinomacropeptide prepared from pepsin-hydrolysis of kappa-CN (at pH 2.5) eluted as multiple peaks...... with apparent MW of 35, 18, and 9 kDa, again independently of pH. Hydrolysis of kappa-CN with chymosin or pepsin at different pH values (pH 2.5, 3.4, and 6.6) produced differently sized aggregates of CMP, largely depending on the pH of the hydrolysis. These results indicate that, whereas CMP molecules...

  1. Untersuchungen zur Proteolyse von para-k-Casein: vom Modell zum Käse

    OpenAIRE

    Böhm, Anke

    2003-01-01

    Para-k-Casein entsteht durch Hydrolyse des kappa-Caseins nach Zugabe proteolytischer Enzyme zur Milch. Untersuchungen an selbst erstellten Modellen unter Bedingungen, die die Käsereifung simulieren, zeigen, dass die Proteolyse des für die Käsereifung bedeutenden para-k-Caseins stark vom Wassergehalt abhängt. Mit Hilfe geeigneter Methoden (SDS-Elektrophorese, IEF, GPC, RP-HPLC, ESI-MS u.a.) konnte der Abbau des para-k-Caseins durch die industriell relevanten Milchgerinnungsenzyme Chymosin, Fro...

  2. Effect of coagulant type and storage temperature on the functionality of reduced-fat Mozzarella cheese

    OpenAIRE

    Sheehan, Jeremiah; O'Sullivan, Kathleen; Guinee, Timothy

    2004-01-01

    Effets du type de coagulant et de la température de stockage sur la fonctionnalité de la Mozzarella à faible teneur en lipides. Les fromages Mozzarella à faible humidité et à faible teneur en matière grasse (~10 %, w/w, matière grasse) ont été produits en triple en utilisant un de ces coagulants : chymosine produite par fermentation (FPC), protéinase de Rhizomucor miehei (RMP) ou protéinase de Rhizomucor pusillus (RPP). Les coagulants ont été ajoutés au lait à une concentration donnée, de man...

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

    OpenAIRE

    7; ,; Sharma, Rajan; Rajput, Yudhishthir; Mann, Bimlesh

    2013-01-01

    International audience 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 wi...

  4. Ultrafiltrasyon Tekniği ile Salamura Beyaz Peynir Üretiminde Kalite Üzerine Değişik Maya Enzimlerinin Etkisi

    OpenAIRE

    Yetişmeyen, Atilla; Çimer, Atilla; Özer, Melike; Odabaşı, Sabiha; Deveci, Orgun

    1998-01-01

    In this study, a microbial enzyme and calf rennet were used to manufacture Turkish White Pickled cheese from ultrafiltrated milk. The ultrafiltration of the skim milk was achieved with volume reduction of 65.2% by using Dow Denmark A/S, Lab-Anlage M20 UF(1) equipment. The calf rennet at a strength of 1/15.000 was composed of a mixture of chymosin/pepsin (90:10) while the microbial enzyme at a strength of 1/196.000 was obtained from Mucor miehei. The physical, chemical and organoleptic propert...

  5. Partial calcium depletion during membrane filtration affects gelation of reconstituted milk protein concentrates.

    Science.gov (United States)

    Eshpari, H; Jimenez-Flores, R; Tong, P S; Corredig, M

    2015-12-01

    Milk protein concentrate powders (MPC) with improved rehydration properties are often manufactured using processing steps, such as acidification and high-pressure processing, and with addition of other ingredients, such as sodium chloride, during their production. These steps are known to increase the amount of serum caseins or modify the mineral equilibrium, hence improving solubility of the retentates. The processing functionality of the micelles may be affected. The aim of this study was to investigate the effects of partial acidification by adding glucono-δ-lactone (GDL) to skim milk during membrane filtration on the structural changes of the casein micelles by observing their chymosin-induced coagulation behavior, as such coagulation is affected by both the supramolecular structure of the caseins and calcium equilibrium. Milk protein concentrates were prepared by preacidification with GDL to pH 6 using ultrafiltration (UF) and diafiltration (DF) followed by spray-drying. Reconstituted UF and DF samples (3.2% protein) treated with GDL showed significantly increased amounts of soluble calcium and nonsedimentable caseins compared with their respective controls, as measured by ion chromatography and sodium dodecyl sulfate-PAGE electrophoresis, respectively. The primary phase of chymosin-induced gelation was not significantly different between treatments as measured by the amount of caseino-macropeptide released. The rheological properties of the reconstituted MPC powders were determined immediately after addition of chymosin, both before and after dialysis against skim milk, to ensure similar serum composition for all samples. Reconstituted samples before dialysis showed no gelation (defined as tan δ=1), and after re-equilibration only control UF and DF samples showed gelation. The gelation properties of reconstituted MPC powders were negatively affected by the presence of soluble casein, and positively affected by the amount of both soluble and insoluble

  6. Characterization of enzymatically induced aggregation of casein micelles in natural concentration by in situ static light scattering and ultra low shear viscosimetry

    DEFF Research Database (Denmark)

    Lehner, D.; Worning, Peder; G, Fritz; L, Ogendal; R, Bauer; Glatter, O.

    1999-01-01

    indirect Fouriertransformation and by the polydispersity inversion technique which led to pair distance distributionfunctions and size distribution function, respectively. The minimum scattering angle was 1 degrees, whichallows for the determination of particle sizes up to a maximum diameter of 12 mum. The......The aggregation of casein micelles in undiluted skim milk after the addition of chymosin was studied bystatic light scattering and ultra low shear viscometry. The static light scattering measurements were madewith two different sample thicknesses, 72 and 16 mum. The scattering data were analyzed by...

  7. 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

  8. 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.

  9. Proteinases from buckwheat (Fagopyrum esculentum moench seeds: Purification and properties of the 47 kDa enzyme

    Directory of Open Access Journals (Sweden)

    Timotijević Gordana S.

    2006-01-01

    Full Text Available Aspartic proteinases from buckwheat seeds are analyzed. Three forms of 47 kDa, 40 kDa and 28 kDa, were purified from mature buckwheat seeds, while two forms of 47 kDa and 28 kDa were detected in developing buckwheat seeds using pepstatin A affinity chromatography. A form of 47 kDa was selectively precipitated from other forms by ammonium sulfate precipitation. This enzyme resembles the chymosin-like pattern of proteolytic activity, as it was shown using BSA and k-casein as substrates, clarifying its ability for milk-clotting. The 47 kDa aspartic proteinase form is localized in the membrane fraction. .

  10. Enzymatically controlled material design with casein--from defined films to localized deposition of particles.

    Science.gov (United States)

    Strube, Oliver I; Rüdiger, Arne A; Bremser, Wolfgang

    2015-05-10

    A new concept for deposition and material design of coatings from biological compounds is presented. An enzymatic reaction triggers the specific coagulation of particles on a support surface. The first examined model system is casein and is based on the natural rennet reaction as applied in the process of cheese-making. The aspartic protease chymosin is immobilized on a support surface and cleaves the hydrophilic parts of the casein micelles, inducing deposition. The concept allows for a high level of control over film characteristics and enables the formation of site-specific film structures. The variability rages from formation of casein films with several micrometers film thickness to the targeted deposition of casein micelles. PMID:25456052

  11. Mucor miehei's microbial rennin production characteristics in a fed-batch proccess

    Directory of Open Access Journals (Sweden)

    C. P. Sánchez Henao

    2011-12-01

    Full Text Available The Mucor miehei zygomycete produces an acid protease (EC:3.4.23.10 resembling calf rennet chymosin characteristics. It has been suggested that low glucose concentration levels could be why enzyme synthesis, co-mes to an end even though enzyme production is still great (Escobar and Barnett, 1993, 1995. To overcome this possible limitation, a two stage research process was designed; the relationship between protease production and sugar consumption was studied initially to determine the periods of time when enzyme production is still high and glucose concentration close to zero. The following stage concentrated on developing a glucose fed-batch process during the afore mentioned time periods to observe any increase or decrease in enzyme production. During the batch studies, it was found that maximum enzyme activity (EA was 165 UC/ml for an average glucose consumption rate of 0.1813 g/1 h. Based on the previous.

  12. Physiological and Biochemical Characteristics of Lactation in Half-lactating Yak

    Institute of Scientific and Technical Information of China (English)

    ZHENG Yu-cai; ZHONG Guang-hui; WANG Yong; PENG Xian-wen; MAO Yong-jiang; ZOU Si-xiang; CHEN Wei-hua; CHEN Jie

    2002-01-01

    Yaks of two lactating types, the half-lactating yak and the total lactating yak, were investigated in their milk compositions, milk coagulation properties, and contents of three kinds of hormones, glucose,and protein in plasma. The half-lactating Maiwa yak and Jiulong yak contained significantly higher contents of protein, fat, and activities of alkaline phosphatase and γ-glutamyl transpeptidase in milk than that of the corresponding total-lactating yak breeds, with reduced milk yield and similar lactose level and relative percentages of main milk protein components. The half-lactatin yak resembled yaks in a late stage of lactation in their biochemical composition of milk; however, significant differences were also observed, which indicated that the former was in a special stage of lactation quite different from dairy cows. Milk of the total-lactating or halflactating yaks could be coagulated normally by adding chymosin, with a similar coagulation time. No significant difference was observed between prolactin and progesterone concentrations in plasma of the half-lactating yaks and total-lactating yaks; however, half-lactating yaks had significantly lower level of oestradiol-17 β in plasma than total-lactating yaks.

  13. Improvement of heterologous protein production in Aspergillus oryzae by RNA interference with alpha-amylase genes.

    Science.gov (United States)

    Nemoto, Takashi; Maruyama, Jun-ichi; Kitamoto, Katsuhiko

    2009-11-01

    Aspergillus oryzae RIB40 has three alpha-amylase genes (amyA, amyB, and amyC), and secretes alpha-amylase abundantly. However, large amounts of endogenous secretory proteins such as alpha-amylase can compete with heterologous protein in the secretory pathway and decrease its production yields. In this study, we examined the effects of suppression of alpha-amylase on heterologous protein production in A. oryzae, using the bovine chymosin (CHY) as a reporter heterologous protein. The three alpha-amylase genes in A. oryzae have nearly identical DNA sequences from those promoters to the coding regions. Hence we performed silencing of alpha-amylase genes by RNA interference (RNAi) in the A. oryzae CHY producing strain. The silenced strains exhibited a reduction in alpha-amylase activity and an increase in CHY production in the culture medium. This result suggests that suppression of alpha-amylase is effective in heterologous protein production in A. oryzae. PMID:19897917

  14. 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.

  15. Gastrointestinal tract and digestion in the young ruminant: ontogenesis, adaptations, consequences and manipulations.

    Science.gov (United States)

    Guilloteau, P; Zabielski, R; Blum, J W

    2009-10-01

    Young calves have to deal with at least three major situations that require profound physiological and digestive adaptations: adaptation to extra-uterine life (up to the first postnatal week), maintenance at a pre-ruminant stage over a long period (3 to 5 months or more), and weaning. This paper reports results obtained on the development (growth and differentiation) of the gastrointestinal tract, and on digestive enzyme activities as well as some aspects of the regulation by gut regulatory peptides. In the newborn calf, the maturation of the small intestine depends on pregnancy duration (preterm vs. full term) and ingestion of colostrum from first milking. The function of gut enterocytes evolves along with the changes from fetal to adult enterocytes. The origin of dietary protein in pre-ruminant and weaning calves modifies SI morphology. Chymosin, elastase II and lactase are typical postnatal enzymes, whereas pepsin, ribonuclease and amylase become important especially following weaning. Nitrogen digestibility increases during the first month of life and is modified by replacement of skim milk powder with non-milk proteins. Milk formula supplementation with Nabutyrate increases pancreatic secretions and digestibility. The gastrointestinal tract development depends on gut regulatory peptides plasma and luminal concentrations. The response to exogenous peptides is in relation with their number and type of functional receptors and with the animal age. Experimental work with young ruminants is important not only for the species involved, but also for its implications to other mammalians. PMID:19996480

  16. 水产品下脚料高值化利用技术研究现状%High-value Utilization Technology of Aquatic Waste

    Institute of Scientific and Technical Information of China (English)

    李晶

    2012-01-01

    The deep development and utilization of aquatic waste is summarized briefly, these aquatic waste can be used in food natural fungicide, chymosin, thioguanine, chondroitin sulfate, dennatan sulfate, oligomeric peptides, small peptides oral solution, CMC, meaty flavor, fish enzyme, glyeopruteins and taurine, which provided a reference for further development and utilization of fish waste resources.%简单综述了水产品下脚料深度开发利用的研究情况,主要可应用在食品天然防霉剂、凝乳酶、硫鸟嘌呤(6 -TG)、硫酸软骨素、硫酸皮肤素、寡聚肽、小分子肽口服液、高吸收性钙剂(CMC)、热反应型肉香调味基料、鱼酶、糖蛋白、牛磺酸中,为进一步开发利用鱼下脚料资源提供参考.

  17. The Role Of Milk Peptide As Antimicrobial Agent In Supporting Health Status

    Directory of Open Access Journals (Sweden)

    Eni Kusumaningtyas

    2013-06-01

    Full Text Available Antimicrobial peptide is commonly present in all species as a component of their innate immune defense against infection. Antimicrobial peptides derived from milk such as isracidin, casocidin, casecidin and other fragments with variety of amino acid sequence are released upon enzymatic hydrolysis from milk protein К-casein, α-casein, β-casein, α-lactalbumin and β- lactoglobulin. These peptides were produced by the activity of digestive or microbial protease such as trypsin, pepsin, chymosin or alcalase. The mode of action of these peptides is by interaction of their positive with negative charge of target cell membrane leading to disruption of membrane associated with physiological event such as cell division or translocation of peptide across the membrane to interact with cytoplasmic target. Modification of charged or nonpolar aliphatic residues within peptides can enhance or reduce the activities of the peptides against a number of microbial strains and it seems to be strain dependent. Several peptides act not only as an antimicrobial but also as an angiotensin-converting enzyme inhibitor, antioxidant, immunomodulator, antiinflamation, food and feed preservative. Although the commercial production of these peptides is still limited due to lack of suitable large-scale technologies, fast development of some methods for peptide production will hopefully increase the possibility for mass production.

  18. Detection and confirmation of milk adulteration with cheese whey using proteomic-like sample preparation and liquid chromatography-electrospray-tandem mass spectrometry analysis.

    Science.gov (United States)

    Campos Motta, T M; Hoff, R B; Barreto, F; Andrade, R B S; Lorenzini, D M; Meneghini, L Z; Pizzolato, T M

    2014-03-01

    Caseinomacropeptide (CMP) is a peptide released by chymosin in cheese production, remaining in whey. Thus, CMP can be used as a biomarker to fluid milk adulteration through whey addition. Commonly, CMP is analyzed by reversed phase (RP-HPLC) or size-exclusion chromatography (SEC). However, some psychrotropic microorganisms - specially Pseudomonas fluorescens - when present in storaged milk, can produce, by enzymatic pathway, a CMP-like peptide generally called pseudo-CMP. These two peptides differ from each other only by one amino acid. RP-HPLC and SEC methods are unable to distinguish these two peptides, which demand development of a confirmatory method with high selectivity. Considering the several degrees of glycosilation and phosphorylation sites in CMP, allied with possible genetic variation (CMP A and CMP B), analytical methods able to differentiate these peptides are extremely complex. In the present work, we developed a proteomic-like technique for separation and characterization of these peptides, using liquid chromatography coupled to mass spectrometry with electrospray ionization able to differentiate and subsequently quantify CMP and pseudo-CMP in milk samples in order to identify adulteration or contamination of these products. The method shows satisfactory precision (<11%) with a detection limit of 1.0 µg mL(-1) and quantification limit of 5.0 µg mL(-1). Specificity, matrix effects and applicability to real samples analysis were also performed and discussed. PMID:24468402

  19. 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. PMID:23396893

  20. Theory Of Salt Effects On Protein Solubility

    Science.gov (United States)

    Dahal, Yuba; Schmit, Jeremy

    Salt is one of the major factors that effects protein solubility. Often, at low salt concentration regime, protein solubility increases with the salt concentration(salting in) whereas at high salt concentration regime, solubility decreases with the increase in salt concentration(salting out). There are no quantitative theories to explain salting in and salting out. We have developed a model to describe the salting in and salting out. Our model accounts for the electrostatic Coulomb energy, salt entropy and non-electrostatic interaction between proteins. We analytically solve the linearized Poisson Boltzmann equation modelling the protein charge by a first order multipole expansion. In our model, protein charges are modulated by the anion binding. Consideration of only the zeroth order term in protein charge doesn't help to describe salting in phenomenon because of the repulsive interaction. To capture the salting in behaviour, it requires an attractive electrostatic interaction in low salt regime. Our work shows that at low salt concentration, dipole interaction is the cause for salting in and at high salt concentration a salt-dependent depletion interaction dominates and gives the salting out. Our theoretical result is consistent with the experimental result for Chymosin protein NIH Grant No R01GM107487.

  1. Assessment of IgE and IgG4 Binding Capacities of Cow's Milk Proteins Selectively Altered by Proteases.

    Science.gov (United States)

    Charcosset, Alexandre; Adel-Patient, Karine; Dupont, Christophe; Bernard, Hervé

    2016-05-01

    Specific IgE and IgG4 have been reported to play key roles in the context of IgE-mediated cow's milk allergy (CMA), but the persistence of their epitopes in milk hydrolysates has not been evaluated. Using sera from 32 CMA patients, 6 CMA patients treated by epicutaneous therapy (CM-treated), and 4 CM-tolerant peanut allergic patients, we analyzed the IgE and IgG4 binding capacities related to major milk allergens in processed milk. Different proteases (plasmin, chymosin, α-chymotrypsin, or pepsin) were used progressively and selectively to hydrolyze β-lactoglobulin (β-LG) and casein (CN) in milk. We then showed that proteases differentially affect IgE or IgG4 immunoreactivities of CN and β-LG and also that we could not relate IgE and/or IgG4 levels or specificities to milk hydrolysates to the clinical status of the patients. PMID:27015440

  2. Anisotropic Contributions to Protein-Protein Interactions.

    Science.gov (United States)

    Quang, Leigh J; Sandler, Stanley I; Lenhoff, Abraham M

    2014-02-11

    The anisotropy of shape and functionality of proteins complicates the prediction of protein-protein interactions. We examine the distribution of electrostatic and nonelectrostatic contributions to these interactions for two globular proteins, lysozyme and chymosin B, which differ in molecular weight by about a factor of 2. The interaction trends for these proteins are computed in terms of contributions to the osmotic second virial coefficient that are evaluated using atomistic models of the proteins. Our emphasis is on identifying the orientational configurations that contribute most strongly to the overall interactions due to high-complementarity interactions, and on calculating the effect of ionic strength on such interactions. The results emphasize the quantitative importance of several features of protein interactions, notably that despite differences in their frequency of occurrence, configurations differing appreciably in interaction energy can contribute meaningfully to overall interactions. However, relatively small effects due to charge anisotropy or specific hydration can affect the overall interaction significantly only if they contribute to strongly attractive configurations. The results emphasize the necessity of accounting for detailed anisotropy to capture actual experimental trends, and the sensitivity of even very detailed atomistic models to subtle solution contributions. PMID:26580057

  3. Biosynthesis of some Mannich bases

    Directory of Open Access Journals (Sweden)

    Bruna S. D. R. Aranha

    2012-06-01

    Full Text Available The Mannich reaction is extremely useful to form molecules that contain nitrogen groups. Currently, there is a great interest turned to this class of compounds due to its biological properties. The recent literature reports that the utilization of enzymes can be an adequate methodology on this type of reaction. According to the exposed above and with the intention of synthesizing the -aminoketones, some catalysts like Chymosin and also some microorganisms such as Saccharomyces cerevisiae, (sourdough bread and Lactobacilos (ATCC 90827LA10N19.10-E.U.A were applied. These reactions were carried out by using water as solvent at room temperature excelling for the Green Chemistry principles. Figure 1 shows the reaction scheme involving 1 eq.mol of aniline, 1,3 eq.mol of formaldehyde, 10 ml of water and 0,25g of the catalyst during four days. The reaction furnished satisfactory yields which are in accordance with the literature data.