Sample records for raw potato starch

  1. Production of pullulan from raw potato starch hydrolysates by a new strain of Auerobasidium pullulans.

    Wu, Shengjun; Lu, Mingsheng; Chen, Jing; Fang, Yaowei; Wu, Leilei; Xu, Yan; Wang, Shujun


    In the present study, hydrolysis of potato starch with marine cold-adapted α-amylase and pullulan production from the hydrolysates by a new strain of Auerobasidium pullulans isolated from sea mud were conducted. The hydrolysis conditions were optimized as follows: reaction time 2h, pH 6.5, temperature 20°C, and α-amylase amount 12 U/g. Under these optimum hydrolysis conditions, the DE value of the potato starch hydrolysates reached to 49.56. The potato starch hydrolysates consist of glucose, maltose, isomaltose, maltotriose, and trace of other maltooligosaccharides with degree of polymerization ranged 4-7. The maximum production of pullulan at 96 h from the hydrolysate of potato starch was 36.17 g/L, which was higher than those obtained from glucose (22.07 g/L, p<0.05) and sucrose (31.42 g/L, p<0.05). Analysis of the high performance liquid chromatography of the hydrolysates of the pullulan product with pullulanase indicated that the main composition is maltotriose, thus confirming the pullulan structure of this pullulan product.

  2. Structure of potato starch

    Bertoft, Eric; Blennow, Andreas


    are interconnected by long chains with more than 36 residues. The clusters consist of still smaller, very tightly branched building blocks. The clusters direct the semicrystalline structures found inside the starch granules. The crystals, which are ~5.2. nm thick, contain double helices formed from the external...... chains extending from the clusters. A range of enzymes is involved in the biosynthesis of the cluster structures and linear segments. These are required for sugar activation, chain elongation, branching, and trimming of the final branching pattern. As an interesting feature, potato amylopectin...... is substituted with low amounts of phosphate groups monoesterified to the C-3 and the C-6 carbons of the glucose units. They seem to align well in the granular structure and have tremendous effects on starch degradation in the potato and functionality of the refined starch. A specific dikinase catalyzes...

  3. Rheological properties of sweet potato starch before and after denaturalization

    肖华西; 林亲录; 夏新剑; 李丽辉; 林利忠; 吴卫国


    Based on the sweet potato starch,cationic starch,acetic starch and cationic-acetic compoundedly modified starch were made through chemical denaturalization.The above three kinds of static rheological parameter and dynamic rheological parameter were measured,respectively.The experimental result reveals that the thermal stability of starchy viscosity increases after chemical denaturalization.Under the condition of identical shearing rate,the shear stress of cationic-acetic ester compoundedly modified sweet potato starch paste is the largest among these kinds of sweet potato starch.This attributes to a phenomenon of shearing thinning.Furthermore,raw sweet potato starch has a larger gel intensity than that of modified starch.

  4. Characterization of potato leaf starch.

    Santacruz, Stalin; Koch, Kristine; Andersson, Roger; Aman, Per


    The starch accumulation-degradation process as well as the structure of leaf starch are not completely understood. To study this, starch was isolated from potato leaves collected in the early morning and late afternoon in July and August, representing different starch accumulation rates. The starch content of potato leaves varied between 2.9 and 12.9% (dry matter basis) over the night and day in the middle of July and between 0.6 and 1.5% in August. Scanning electron microscopy analyses of the four isolated starch samples showed that the granules had either an oval or a round shape and did not exceed 5 microm in size. Starch was extracted by successive washing steps with dimethyl sulfoxide and precipitated with ethanol. An elution profile on Sepharose CL-6B of debranched starch showed the presence of a material with a chain length distribution between that generally found for amylose and amylopectin. Amylopectin unit chains of low molecular size were present in a higher amount in the afternoon than in the morning samples. What remains at the end of the night is depleted in specific chain lengths, mainly between DP 15 and 24 and above DP 35, relative to the end of the day.

  5. Potato starch synthases

    Nazarian-Firouzabadi, Farhad; Visser, Richard G.F.


    Starch, a very compact form of glucose units, is the most abundant form of storage polyglucan in nature. The starch synthesis pathway is among the central biochemical pathways, however, our understanding of this important pathway regarding genetic elements controlling this pathway, is still

  6. Potato starch synthases

    Nazarian-Firouzabadi, Farhad; Visser, Richard G.F.


    Starch, a very compact form of glucose units, is the most abundant form of storage polyglucan in nature. The starch synthesis pathway is among the central biochemical pathways, however, our understanding of this important pathway regarding genetic elements controlling this pathway, is still insuffic

  7. Substituent distribution within cross-linked and hydroxypropylated sweet potato starch and potato starch

    Zhao, J.; Schols, H.A.; Chen Zenghong,; Jin Zhengyu,; Buwalda, P.L.; Gruppen, H.


    Revealing the substituents distribution within starch can help to understand the changes of starch properties after modification. The distribution of substituents over cross-linked and hydroxypropylated sweet potato starch was investigated and compared with modified potato starch. The starches were

  8. Sorption properties of modified potato starch

    Teresa Witczak


    Full Text Available Background. Starch is one of the biopolymers most commonly used in the food industry. In its native form its applications are limited. In contrast, its structure is relatively readily modified using various methods, producing starch derivatives of greatly diverse properties. The primary methods used to change characteristics of starch include acetylation and oxidation. Thus obtained raw materials are used as food additives. Stability of these raw materials and food products to a considerable extent depends on their composition and parameters characterizing storage facilities, i.e. relative humidity and temperature. One of the methods to specify adequate ambient conditions is based on water activity supplemented by sorption isotherms. As a result studies investigating correlations between water activity and moisture content are of importance for the optimization of storage conditions and design of certain food processing procedures. For this reason the aim of this study was to assess the effect of modification (oxidation, acetylation and their combination on sorption properties (described based on sorption isotherms of potato starch. Material and methods. Analyses were conducted on potato starch and its derivatives produced by acetylation, oxidation and co-modification (acetylation coupled with oxidation. Starch was oxidized using sodium chlorate (I, while acetylation was run using anhydrous acetic acid. Sorption isotherms were determined by the static desiccator method. Results were described applying selected mathematical methods equipped with physical interpretations (BET and GAB and empirical models (Halsey, Oswin, Henderson, Pelega, Lewicki, Blahovec-Yanniotis. Calculations were made using non-linear estimation. Results. The greatest water absorbability was found for native potato starch. Modifications caused a decrease in the amount of adsorbed water vapour, dependent on the applied modification. Acetylation resulted in significantly

  9. The Rheological Property of Potato Starch Adhesives

    Junjun Liu


    Full Text Available The main goal of this study was to use potato starch in the production of environmentally sound adhesives. ‘Three-formaldehyde glue’ pollutes the environment and harms to human health strongly, which widely used for wood-based panels preparation. Environment-friendly potato starch adhesives were prepared using method of oxidation-gelatinization, insteading of the three formaldehyde glue. The effects of the quality ratio of starch and water, temperature and shear rate on the apparent viscosity of the adhesive were studied. The rheological eigenvalue of apparent viscosity was studied through nonlinear regression. The results showed that the apparent viscosity of potato starch adhesives decreased with the increasing of temperature; the apparent viscosity decreased slowly with the increasing of rotor speed; the phenomenon of shear thinning appeared within potato starch adhesives which was pseudo-plastic fluids. Potato starch adhesives with characteristics of non-toxic, no smell and pollution could be applied in interior and upscale packaging.

  10. Studies of Amylose Content in Potato Starch

    Potato starch is typically low in amylose (~20-25%), but high amylose starch has superior nutritional qualities. The ratio between amylose and amylopectin is the most important property influencing the physical properties of starch. There is a strong case to be made for the development of food crops...

  11. Food preparation characteristics of potato starch pastes containing a proportion of chemically-modified starch

    菊地, 和美; 高橋 セツ子; 吉田 訓子; 山本 未穂; 知地 英征; Kazumi, KIKUCHI; Takahashi, Setsuko; Yoshida, Kuniko; Yamamoto, Miho; Chiji, Hideyuki; 藤女子大学人間生活学部食物栄養学科; 藤女子大学人間生活学部食物栄養学科藤女子大学大学院人間生活学研究科食物栄養学専攻


    Hokkaido potatoes are widely used as a source of starch. Potato starch is used for various purposes,particularly for the production of fish paste products,livestock products, and confectionery. Moreover, modified starch, which is produced by processing potato starch chemically and physically, is used in a variety of forms. This study examines the properties of modified starch gels produced by further enhancing the starch functions of potato starch. To study the primary properties of starch ge...

  12. Heterologous expression of two Arabidopsis starch dikinases in potato

    Xu, Xuan; Dees, Dianka; Huang, Xing Feng; Visser, Richard G.F.; Trindade, Luisa M.


    Starch phosphate esters influence physiochemical properties of starch granules that are essential both for starch metabolism and industrial use of starches. To modify properties of potato starch and understand the effect of starch phosphorylation on starch metabolism in storage starch, the starch di

  13. Effect of adsorption of an inhibitory factor on raw starch hydrolysis by glucoamylase.

    Towprayoon, S; Fujio, Y; Ueda, S


    An inhibitory factor (IF) produced byAspergillus niger strain 19, and which inhibits the action of glucoamylase on starch, has the ability to be tightly adsorbed on to various raw starches, though the amount differs from starch to starch. Based on the hydrolysis of the IF-starch complex by glucoamylase, the inhibitions per unit IF adsorbed are similar for some varieties of starch. The effectiveness ratio of IF (% hydrolysis inhibition per % IF adsorbed on raw starch) for corn, sweet potato, waxy rice and waxy corn starches are 1.1, 1.0, 0.85 and 0.96, respectively. These results support the hypothesis that both glucoamylase and IF are adsorbed on to a common binding site on raw starch. However, the effectiveness ratio of IF for cassava and wheat starches are 0.71 and 1.65, respectively, which differ significantly from other varieties of starch.

  14. Rheological and Thermal Properties of Potato Starch

    Zhong Geng; Li Tian-zhen; Zhang Wei-min; Li Hao-nan


    Particle size, rheological and thermal properties of potato starch from Yunnan province of China was in-vestigated. The particle size ranges from 0.429-102.3 um determined by laser light-scatter. The major flow type of 6 w/v% potato starch was shear-thinning fluid even the shear rate up to 800·s-1, and the gel formed by 6 w/v% potato starch fell to weak gel for its little difference between G' and G'', high dependence on frequency and low value of G'(Pa). The hardness and cohesiveness of potato starch gel were 31.3 g and 131.9 g·s, respectively. The thermal properties of potato starch were also determined by DSC at the starch:water=3:1. The To, Tp, and ΔH of potato starch were 62.23℃,67.31℃, and 2.22 J·g-1.


    A. Sh. Mannapova


    Full Text Available Here in this article the justification of expediency of enzyme resistant starch use in therapeutic food products is presented . Enzyme resistant starch is capable to resist to enzymatic hydrolysis in a small intestine of a person, has a low glycemic index, leads to decrease of postprandial concentration of glucose, cholesterol, triglycerides in blood and insulin reaction, to improvement of sensitivity of all organism to insulin, to increase in sense of fulness and to reduction of adjournment of fats. Resistant starch makes bifidogenшс impact on microflora of a intestine of the person, leads to increase of a quantity of lactobacillus and bifidobacterium and to increased production of butyric acid in a large intestine. In this regard the enzyme resistant starch is an important component in food for prevention and curing of human diseases such as diabetes, obesity, colitis, a cancer of large and direct intestine. One method is specified by authors for imitation of starch digestion in a human body. This method is based on the definition of an enzyme resistance of starch in vitro by its hydrolysis to glucose with application of a glucoamylase and digestive enzyme preparation Pancreatin. This method is used in researches of an enzyme resistance of starch, of genetically modified potato, high amylose corn starch Hi-Maize 1043 and HYLON VII (National Starch Food Innovation, USA, amylopectin and amylose. It is shown that the enzyme resistance of the starch emitted from genetically modified potatoes conforms to the enzyme resistance of the high amylose corn starch “Hi-Maize 1043 and HYLON VII starch”, (National Starch Food Innovation, the USA relating to the II type of enzyme resistant starch. It is established that amylopectin doesn't have the enzyme resistant properties. The results of researches are presented. They allow us to make the following conclusion: amylose in comparison with amylopectin possesses higher enzyme resistance and gives to

  16. Starch removal from potato tuber sections.

    Fronda, A; Jona, R


    Heating plant sections at 90 C with 0.5% aqueous ammonium oxalate is required to remove pectins. When applied to tissues rich in starch such as potato, this step produces heavy dextrinization of the starch which hinders subsequent evaluation of the extinction values of the cell walls. To overcome this a method has been devised to brush away the starch granules from the sections with a thin paint brush, just after paraffin removal by xylene. The slide is then processed as usual: pectins are removed by heat treatment, cell walls are stained with PAS and the stain intensity can be evaluated by photometry.

  17. The heat insulating properties of potato starch extruded with addition of chosen by- products of food industry

    Zdybel Ewa


    Full Text Available The study was aimed at determination of time of heat transition through the layer of quince, apple, linen, rose pomace and potato pulp, as well as layer of potato starch and potato starch extruded with addition of above mentioned by-products. Additionally the attempt of creation a heat insulating barrier from researched raw material was made. The heat conductivity of researched materials was dependent on the type of material and its humidity. Extruded potato starch is characterized by smaller heat conductivity than potato starch extruded with addition of pomace. The obtained rigid extruded starch moulders were characterized by higher heat insulating properties than the loose beads. It is possible to use starch and by-products of food industry for production of heat insulating materials.

  18. Amylose Content in Tuber Starch of Wild Potato Species

    Approximately 20% of potato tuber fresh weight is starch, which is composed of amylose (straight chains of glucose) and amylopectin (branched chains). Potato starch is low in amylose (~25%), but high amylose starch has superior nutritional qualities. Amylose content has been determined in tuber samp...

  19. Mechanochemical degradation of potato starch paste under ultrasonic irradiation

    LI Jian-bin; LI Lin; LI Bing; CHEN Ling; GUI Lin


    In the paper, changes in the molecular weight, the intrinsic viscosity and the polydispersity (molecular mass distribution) of treated potato starch paste were studied under different ultrasonic conditions which include irradiation time, ultrasonic intensity, potato starch paste concentration, and distance from probe tip on the degradation of potato starch paste. Intrinsic viscosity of potato starch paste was determined following the ASTM (American Society for Testing and Materials) standard practice for dilute solution viscosity of polymers. Molecular mass and polydispersity of potato starch paste were measured on GPC (Gel Permeation Chromatography). The results showed that the average molecular mass and the intrinsic viscosity of starch strongly depended on irradiation time. Degradation increased with prolonged ultrasonic irradiation time, and the increase of ultrasonic intensity could accelerate the degradation, resulting in a faster degradation rate, a lower limiting value and a higher degradation extent. Starch samples were degraded faster in dilute solutions than in concentrated solutions. The molecular mass and the intrinsic viscosity of starch increased with the increase of distance from probe tip. Our results also showed that the polydispersity decreased with ultrasonic irradiation under all ultrasonic conditions. Ultrasonic degradation of potato starch paste occured based on the mechanism of molecular relaxation of starch paste. In the initial stage, ultrasonic degradation of potato starch paste was a random process, and the molecular mass distribution was broad. After that, ultrasonic degradation of potato starch paste changed to a nonrandom process, and the molecular mass distribution became narrower. Finally, molecular mass distribution tended toward a saturation value.

  20. Use of biomass energy. Saccharification of raw starch and ethanol fermentation

    Ueda, S.


    Raw starch was saccharified under acidic condition of pH 3.5 using black-koji amylase, and the resultant saccharidies were fermented to give ethanol in succession. White polished rice flour was fermented at 30 degrees C during the period of 7 to 10 days to give ethanol. Semi-continuous ethanol fermentation was carried out using corn starch and cassava starch. Batch ethanol fermentation was also carried out using cassava or sweet potato. Sweet potato was fermented using Rhizopus gluco-amylase. 11 references.

  1. Inhibitory effect of chlorogenic acid on digestion of potato starch.

    Karim, Zida; Holmes, Melvin; Orfila, Caroline


    The effect of the chlorogenic acid isomer 5-O-caffeoylquinic acid (5-CQA) on digestion of potato starch by porcine pancreatic alpha amylase (PPAA) was investigated using isolated starch and cooked potato tuber as substrates. In vitro digestion was performed on five varieties of potato with varying phenolic content. Co- and pre-incubation of PPAA with 5-CQA significantly reduced PPAA activity in a dose dependent manner with an IC50 value of about 2mgmL(-1). Lineweaver-Burk plots indicated that 5-CQA exerts a mixed type inhibition as km increased and Vmax decreased. The total polyphenol content (TPC) of peeled tuber tissue ranged from 320.59 to 528.94mg 100g(-1)dry weight (DW) in raw tubers and 282.03-543.96mg 100g(-1)DW in cooked tubers. With the exception of Désirée, TPC and 5-CQA levels decreased after cooking. Principle component analysis indicated that digestibility is affected by multiple factors including phenolic, dry matter and starch content.

  2. Rheological behaviour of heated potato starch dispersions

    Juszczak, L.; Witczak, M.; Ziêba, T.; Fortuna, T.


    The study was designed to investigate the rheological properties of heated potato starch dispersions. Water suspensions of starch were heated at 65, 80 or 95°C for 5, 15, 30 or 60 min. The dispersions obtained were examined for granule size distribution and rheology. It was found that the starch dispersions significantly differed in both respects. The mean diameters of starch granules were largest for the dispersion heated at 65°C and smallest for that heated at 95°C. As the heating temperature was raised, the yield stresses and consistency coefficients decreased, while the flow behaviour indexes and Casson plastic viscosities increased. There were also differences in the viscoelastic properties of the dispersions: for those heated at 65°C the storage and loss moduli increased with heating time whereas for those heated at 80°C both moduli decreased.

  3. Mechanical Properties of Isotactic Polypropylene Modified with Thermoplastic Potato Starch

    Knitter, M.; Dobrzyńska-Mizera, M.


    In this paper selected mechanical properties of isotactic polypropylene (iPP) modified with potato starch have been presented. Thermoplastic starch (TPS) used as a modifier in the study was produced from potato starch modified with glycerol. Isotactic polypropylene/thermoplastic potato starch composites (iPP/TPS) that contained 10, 30, 50 wt.% of modified starch were examined using dynamic mechanical-thermal analysis, static tensile, Brinell hardness, and Charpy impact test. The studies indicated a distinct influence of a filler content on the mechanical properties of composites in comparison with non-modified polypropylene.

  4. Engineering Potato Starch with a Higher Phosphate Content

    Xu, Xuan; Huang, Xing-Feng; Visser, Richard G. F.


    Phosphate esters are responsible for valuable and unique functionalities of starch for industrial applications. Also in the cell phosphate esters play a role in starch metabolism, which so far has not been well characterized in storage starch. Laforin, a human enzyme composed of a carbohydrate-binding module and a dual-specificity phosphatase domain, is involved in the dephosphorylation of glycogen. To modify phosphate content and better understand starch (de)phosphorylation in storage starch, laforin was engineered and introduced into potato (cultivar Kardal). Interestingly, expression of an (engineered) laforin in potato resulted in significantly higher phosphate content of starch, and this result was confirmed in amylose-free potato genetic background (amf). Modified starches exhibited altered granule morphology and size compared to the control. About 20–30% of the transgenic lines of each series showed red-staining granules upon incubation with iodine, and contained higher phosphate content than the blue-stained starch granules. Moreover, low amylose content and altered gelatinization properties were observed in these red-stained starches. Principle component and correlation analysis disclosed a complex correlation between starch composition and starch physico-chemical properties. Ultimately, the expression level of endogenous genes involved in starch metabolism was analysed, revealing a compensatory response to the decrease of phosphate content in potato starch. This study provides a new perspective for engineering starch phosphate content in planta by making use of the compensatory mechanism in the plant itself. PMID:28056069

  5. Effect of starch isolation method on properties of sweet potato starch



    Full Text Available Isolation method of starch with different agents influences starch properties, which provide attention for studying the most appropriate method for isolation of starch. In the present study sweet potato starch was isolated by Sodium metabisulphate (M1, Sodium chloride (M2, and Distilled water (M3 methods and these were assessed for functional, chemical, pasting and structural properties. M3 yielded the greatest recovery of starch (10.20%. Isolation methods significantly changed swelling power and pasting properties but starches exhibited similar chemical properties. Sweet potato starches possessed C-type diffraction pattern. Small size granules of 2.90 μm were noticed in SEM of M3 starch. A high degree positive correlation was found between ash, amylose, and total starch content. The study concluded that isolation methods brought changes in yield, pasting and structural properties of sweet potato starch.

  6. Utilization of Potato Protein Recovered from Wastewater of Potato Starch Factory as Cattle Feed

    Masayuki Takeguchi


    Full Text Available A large amount of wastewater is discharged from potato starch factories in Hokkaido, Japan. The wastewater contains residual potato constituents such as protein, which are named potato fruit juice (PFJ. A powerful stench is generated from PFJ by anaerobic fermentation. In this study, the isoelectric precipitation technique was applied to recover the potato protein from PFJ. Protein recovery from PFJ by acid isoelectric precipitation at pH 3.0 or less reached 80%. PFJ post-protein recovery at pH 3.0 does not produce a powerful stench. Potato protein recovered from PFJ by acid treatment is a useful feed resource. The PFJ in potato starch factory is a potentially promising resource for the production of potato protein. Wastewater from potato starch factories does not have to be waste or a source of powerful stench, it can be a valuable resource.

  7. Microbial starch binding domains are superior to granule bound starch synthase 1 for anchoring luciferase to potato starch granules

    Ji, Q.; Vincken, J.P.; Suurs, L.C.J.M.; Visser, R.G.F.


    Microbial starch-binding domains (SBD) and granule-bound starch synthase I (GBSSI) are proteins which are accumulated in potato starch granules. The efficiency of SBD and GBSSI for targeting active luciferase reporter proteins to granules during starch biosynthesis was compared. GBSSI or SBD sequenc

  8. Influence of completed payment on production profitability of starch potatoes

    Agnieszka Ginter


    Full Text Available Poland is a formal member of the European Union. New rules of Common Agriculture Policy (CAP, the same as in all countries belonging to the European Union (EU operate on agricultural markets. The accession to the EU is beneficial for Polish starch potato producers due to the higher level of profits from productions and selling starch potatoes. The research showed, that completed payment for producers of starch potatoes is very important and they created the level of profitability of this plant.

  9. Thermostable, Raw-Starch-Digesting Amylase from Bacillus stearothermophilus

    Kim, Jaeyoung; Nanmori, Takashi; Shinke, Ryu


    An endospore-forming thermophilic bacterium, which produced amylase and was identified as Bacillus stearothermophilus, was isolated from soil. The amylase had an optimum temperature of 70°C and strongly degraded wheat starch granules (93%) and potato starch granules (80%) at 60°C.

  10. Prebiotic properties of potato starch dextrins

    Renata Barczyńska


    Full Text Available The objective of the present study was to compare the prebiotic properties of starch dextrins, that is, resistant dextrins obtained from potato starch in the process of simultaneous thermolysis and chemical modification, which were selected based on previous research. Both prepared dextrins met the definition criterion of dietary fiber and also the basic prebiotic criterion – they were not degraded by the digestive enzymes of the initial sections of the gastrointestinal tract. The growth of probiotic lactobacilli and bifidobacteria, as well as Escherichia coli, Enterococcus, Bacteroides, and Clostridium strains isolated from feces of healthy people, showed that both studied dextrins were utilized as a source of assimilable carbon and energy by the strains. Furthermore, better growth (higher numbers of cells counts of probiotic bacteria than those of fecal isolates indicated that the studied resistant dextrins showed a selective effect. Both dextrins might be considered as substances with prebiotic properties due to their chemical and physical properties and selectivity towards the studied probiotic bacterial strains.

  11. Tribology of swollen starch granule suspensions from maize and potato.

    Zhang, Bin; Selway, Nichola; Shelat, Kinnari J; Dhital, Sushil; Stokes, Jason R; Gidley, Michael J


    The tribological properties of suspensions of cooked swollen starch granules are characterised for systems based on maize starch and potato starch. These systems are known as granule 'ghosts' due to the release (and removal) of polymer from their structure during cooking. Maize starch ghosts are less swollen than potato starch ghosts, resulting in a higher packing concentration and greater mechanical stability. In a soft-tribological contact, maize ghost suspensions reduce friction compared to the solvent (water), generate bell-shaped tribological profiles characteristic of particle entrainment and show a marked concentration dependence, whereas potato ghost suspensions exhibit lubrication behaviour similar to water. Microscopy analysis of the samples following tribological testing suggests that this is due to the rapid break-up of potato ghosts under the shear and rolling conditions within the tribological contact. A reduction in the small deformation moduli (associated with a weak gel structure) is also observed when the potato ghost suspensions are subjected to steady shear using parallel plate rheometry; both microscopy and particle size analysis show that this is accompanied by the partial shear-induced breakage of ghost particles. This interplay between particle microstructure and the resultant rheological and lubrication dynamics of starch ghost suspensions contributes to an enhanced mechanistic understanding of textural and other functional properties of cooked starches in food and other applications.

  12. Kinetics of the gas-solid hydroxyethylation of potato starch

    Kuipers, N.J M; Beenackers, A.A C M


    The kinetics of the reaction between gaseous ethylene oxide and semidry granular potato starch was studied in a pressure-controlled semibatch reactor with and without impregnation of the starch with the catalyst sodium hydroxide. Four parallel reactions are involved: the catalyzed (with reaction rat

  13. Surface effects in the acetylation of granular potato starch

    Steeneken, P.A.M.; Woortman, A.J.J.


    The occurrence of surface effects in the acetylation of granular potato starch with acetic anhydride to degrees of substitution 0.04-0.2 was studied by two different approaches. The first approach involved the fractionation of granular starch acetates into five different size classes and analysis of

  14. Surface effects in the acetylation of granular potato starch

    Steeneken, P.A.M.; Woortman, A.J.J.


    The occurrence of surface effects in the acetylation of granular potato starch with acetic anhydride to degrees of substitution 0.04-0.2 was studied by two different approaches. The first approach involved the fractionation of granular starch acetates into five different size classes and analysis of

  15. Simultaneous raw starch hydrolysis and ethanol fermentation by glucoamylase from Rhizoctonia solani and Saccharomyces cerevisiae.

    Singh, D; Dahiya, J S; Nigam, P


    Crude glucoamylase preparation from Rhizoctonia solani was used to saccharify raw and cooked starch. Various concentrations of potato starch and wheat flour from 10-40%, w/v were used for mashing but 30% was found to be the optimal and economical. The saccharified mash yielded 5.89%, v/v ethanol in a simultaneous saccharification and fermentation process using a yeast strain Saccharomyces cerevisiae (SC-39) at 35 degrees C for 4 days. Removal of inhibitory substances from the fermenting broth through dialysis caused considerable increase in ethanol production.

  16. Recent advances in microbial raw starch degrading enzymes.

    Sun, Haiyan; Zhao, Pingjuan; Ge, Xiangyang; Xia, Yongjun; Hao, Zhikui; Liu, Jianwen; Peng, Ming


    Raw starch degrading enzymes (RSDE) refer to enzymes that can directly degrade raw starch granules below the gelatinization temperature of starch. These promising enzymes can significantly reduce energy and simplify the process in starch industry. RSDE are ubiquitous and produced by plants, animals, and microorganisms. However, microbial sources are the most preferred one for large-scale production. During the past few decades, RSDE have been studied extensively. This paper reviews the recent development in the production, purification, properties, and application of microbial RSDE. This is the first review on microbial RSDE to date.

  17. Drilling Mud Formulation Using Potato Starch(Ipomoea Batatas



    Full Text Available In the search for suitable local alternatives as additives in the manufacture of drilling muds which is an essential entity in the exploration of oil and gas, some vital considerations must be put in place such as cost and environmental effect. This study focuses on the suitability of locally processed potato starch as a viscosifier and fluid loss agent in drilling mud. Comparative analysis of properties obtained from the prepared potato starch mud and that formulated from Polyanionic cellulose (PAC were carried out. Results from this investigation showed that rheological properties (plastic viscosity and yield point of the potato starch mud increased when the content of both viscosifiers were equal at 1.0g/ 316.4ml of water. Plastic viscosity also increased by 13.6% when potato starch concentration increased by 50%. Also, a combination of PAC and potato starch at a ratio of 1:1 to 0.5:1.5 gave a fluid loss of 7.1 - 7.7 ml which were very close to that of the standard mud at 6.8ml. the pH, mud weight and specific gravity of the formulated mud samples ranged from 7.0 - 9.0, 7.0 - 9.1 and 0.83 - 1.09 respectively, which were all in line with the standard mud specifications.

  18. The use of potato and sweet potato starches affects white salted noodle quality

    Chen, Z.; Schols, H.A.; Voragen, A.G.J.


    Potato and sweet potato starches and derivatives thereof were used to substitute part of the wheat flour in white salted noodle (WSN) manufacture. The quality of the WSN obtained was compared with the quality of WSN made from wheat flour only. When up to 20% of wheat flour was replaced by acetylated

  19. Breeding for improved potato nutrition: High amylose starch potatoes show promise as fiber source

    Potato starch is composed of approximately 75% amylopectin and 25% amylose. We are interested in breeding for higher amylose content, which would increase the fiber content of potato and decrease glycemic index. In order to make progress in a breeding program, we have developed a high throughput ass...

  20. Factors influencing gene silencing of granule-bound starch synthase in potato

    Heilersig, H.J.B.


    In the past, antisense RNA technology was used to modify the composition of potato tuber starch. Potato starch comprises amylose and amylopectin, polymers of glucose. Amylose production in potato is completely dependent on the presence of granule-bound starch synthase I (GBSSI). Inhibition of GBSSI

  1. Physicochemical properties of starches obtained from three varieties of Chinese sweet potatoes.

    Chen Zenghong,; Schols, H.A.; Voragen, A.G.J.


    Starches isolated from 3 typical types of Chinese sweet potato varieties (XuShu18, SuShu2, and SuShu8) were characterized and compared with starches isolated from potato and mung bean. The 3 sweet potato starches differed in granule size; particle size distribution; protein, lipid, and phosphorus co

  2. Development of oxidised and heat-moisture treated potato starch film.

    Zavareze, Elessandra da Rosa; Pinto, Vânia Zanella; Klein, Bruna; El Halal, Shanise Lisie Mello; Elias, Moacir Cardoso; Prentice-Hernández, Carlos; Dias, Alvaro Renato Guerra


    This study investigated the effects of sodium hypochlorite oxidation and a heat-moisture treatment of potato starch on the physicochemical, pasting and textural properties of potato starches in addition to the water vapour permeability (WVP) and mechanical properties of potato starch films produced from these starches. The carbonyl contents, carboxyl contents, swelling power, solubility, pasting properties and gel texture of the native, oxidised and heat-moisture treated (HMT) starches were evaluated. The films made of native, oxidised and HMT starches were characterised by thickness, water solubility, colour, opacity, mechanical properties and WVP. The oxidised and HMT starches had lower viscosity and swelling power compared to the native starch. The films produced from oxidised potato starch had decreased solubility, elongation and WVP values in addition to increased tensile strength compared to the native starch films. The HMT starch increased the tensile strength and WVP of the starch films compared to the native starch.

  3. Screening of seeds prepared from retrograded potato starch to increase retrogradation rate of maize starch.

    Lian, Xijun; Liu, Lizeng; Guo, Junjie; Li, Lin; Wu, Changyan


    In this paper, retrograded potato starches treated by oxalic, hydrochloric and citric acids and/with amylase respectively, as seed crystals, are added into maize starch paste to increase maize starch retrogradation rate. The results show that addition of seed accelerates maize starch retrogradation greatly. Seed prepared from retrograded potato starch treated by oxalic acid increases maize starch retrogradation rate most, from 1.5% to 49%. The results of IR spectra of retrograded maize starch derived from different seeds show that double helix, not hydrogen bond, probably forms at stage of seed growth during retrogradation. The results of IR spectra, X-ray and SEM indicate that treatment of retrograded potato starch with oxalic acid leads to formation of more hydrogen bonds and an increase of seed crystal planes, which markedly promotes the growth of the seed. Retrogradation of maize starch by seeding method surely includes a stage of crystal growth through double helix in a way different from normal maize starch retrogradation.

  4. Characteristics and Utilization of Potato Native Starch and Modified Starch%马铃薯原淀粉及变性淀粉的特点及应用



    Potato native starch is one of the important natural polymer materials and it has been widely applied in food industry, paper manufacturing industry, textile industry, and pharmaceutical industry due to its irreplaceable characteristics. Potato modified starch, which was modified by physical, chemical or other methods, broadens the utilization of potato native starch. Due to the wide distribution and large planting area of potato in China, huge raw materials could be provided for the manufacture of potato native and modified starch. Though affected by raw material and profit issue, potato native starch and modified starch processings are stil booming industry in China and their volumes, types, and utilizations wil be further developed.%马铃薯原淀粉是一种极为重要的天然高分子材料,具有其他植物淀粉不可替代的特性,可广泛用于食品工业、造纸工业、纺织工业和医药工业。通过物理、化学或其他方式将马铃薯原淀粉改造为变性淀粉后进一步拓宽了其用途。中国马铃薯分布广、种植面积大,为马铃薯原淀粉和变性淀粉的加工提供了巨大的原料来源。尽管受原料困扰和效益影响,马铃薯原淀粉和变性淀粉加工业在中国仍属于朝阳产业,产品的数量、种类和用途都将会有进一步的扩展。

  5. Molecular structure and physicochemical properties of potato and bean starches as affected by gamma-irradiation.

    Chung, Hyun-Jung; Liu, Qiang


    In this study, potato and bean starches were treated by gamma-irradiation up to 50kGy. Molecular structure and physicochemical properties of irradiated potato and bean starches were investigated. Microscopic observation under scanning electron microscope (SEM) and polarized microscope showed that some of potato and bean starch granules were destroyed by gamma-irradiation and the breakage was much greater at a higher dose (50 kGy). Carboxyl content and amylose leaching increased, whereas the swelling factor and apparent amylose content decreased after irradiation in both potato and bean starches. The proportions of short (DP 6-12) and long (DP > or = 37) amylopectin chains as well as average chain length increased with increasing irradiation dose. However, the proportion of DP 13-24 decreased by irradiation. The relative crystallinity, the degree of granule surface order, and gelatinization enthalpy decreased with an increase in irradiation dose. The extent of decrease in potato starch was greater than that in bean starch. The exothermic peak around 90-110 degrees C was observed in DSC thermogram when the potato starch was irradiated at 50 kGy. The pasting viscosity significantly decreased with an increase in irradiation dose. The proportion of slowly digestible starch (SDS) decreased and resistant starch (RS) content increased by irradiation in both potato and bean starches. However, the rapidly digestible starch (RDS) of potato starch increased with increasing irradiation dose, whereas the bean starch showed the opposite trend to potato starch in RDS content.

  6. Direct fermentation of raw starch using a Kluyveromyces marxianus strain that expresses glucoamylase and alpha-amylase to produce ethanol.

    Wang, Rongliang; Wang, Dongmei; Gao, Xiaolian; Hong, Jiong


    Raw starch and raw cassava tuber powder were directly and efficiently fermented at elevated temperatures to produce ethanol using the thermotolerant yeast Kluyveromyces marxianus that expresses α-amylase from Aspergillus oryzae as well as α-amylase and glucoamylase from Debaryomyces occidentalis. Among the constructed K. marxianus strains, YRL 009 had the highest efficiency in direct starch fermentation. Raw starch from corn, potato, cassava, or wheat can be fermented at temperatures higher than 40°C. At the optimal fermentation temperature 42°C, YRL 009 produced 66.52 g/L ethanol from 200 g/L cassava starch, which was the highest production among the selected raw starches. This production increased to 79.75 g/L ethanol with a 78.3% theoretical yield (with all cassava starch were consumed) from raw cassava starch at higher initial cell densities. Fermentation was also carried out at 45 and 48°C. By using 200 g/L raw cassava starch, 137.11 and 87.71 g/L sugar were consumed with 55.36 and 32.16 g/L ethanol produced, respectively. Furthermore, this strain could directly ferment 200 g/L nonsterile raw cassava tuber powder (containing 178.52 g/L cassava starch) without additional nutritional supplements to produce 69.73 g/L ethanol by consuming 166.07 g/L sugar at 42°C. YRL 009, which has consolidated bioprocessing ability, is the best strain for fermenting starches at elevated temperatures that has been reported to date.

  7. Enhanced biosynthesis of poly(3-hydroxybutyrate) from potato starch by Bacillus cereus strain 64-INS in a laboratory-scale fermenter.

    Ali, Iftikhar; Jamil, Nazia


    To decrease the polyhydroxyalkanoate (PHA) production cost by supplying renewable carbon sources has been an important aspect in terms of commercializing this biodegradable polymer. The production of biodegradable poly(3-hydroxyalkanoates) (PHA) from raw potato starch by the Bacillus cereus 64-INS strain isolated from domestic sludge has been studied in a lab-scale fermenter. The bacterium was screened for the degradation of raw potato starch by a starch hydrolysis method and for PHA production by Nile blue A and Sudan black B staining. Shake-flask cultures of the bacterium with glucose [2% (w/v)] or raw potato starch [2% (w/v)] produced PHA of 64.35% and 34.68% of dry cell weight (DCW), respectively. PHA production was also carried out in a 5-L fermenter under control conditions that produced 2.78 g/L of PHA and PHA content of 60.53% after 21 hr of fermentation using potato starch as the sole carbon source. Gas chromatography-mass spectroscopy (GC-MS) analyses confirmed that the extracted PHA contained poly(3-hydroxybutyrate) (PHB) as its major constituent (>99.99%) irrespective of the carbon source used. The article describes, for what we believe to be the first time, PHB production being carried out without any enzymatic or chemical treatment of potato starch at higher levels by fermentation. More work is required to optimize the PHB yield with respect to starch feeding strategies.

  8. Occurrence of an Affinity Site apart from the Active Site on the Raw-Starch-Digesting but Non-Raw-Starch-Adsorbable Bacillus subtilis 65 α-Amylase

    Hayashida, Shinsaku; Teramoto, Yuji; Inoue, Takehiro; MITSUIKI, Shinji


    α-Cyclodextrin specifically inhibited raw starch digestion by Bacillus subtilis 65 α-amylase. The raw starch digestibility and α-cyclodextrin-Sepharose 6B adsorbability of this α-amylase were simultaneously lost when the specific domain corresponding to the affinity site essential for raw starch digestion was deleted by proteolysis. Occurrence of the affinity site on raw-starch-digesting enzymes was proven also with bacterial amylase.

  9. Modification of Cilembu sweet potato starch with ethanoic acid

    Mahmudatussa'adah, A.; Rahmawati, Y.; Sudewi


    Cilembu sweet potato harvest was abundant, its use was still limited. Starch was required by various industries. Starch is generally beige, and requires a long time for the drying process. The purpose of this research was to produce a modified starch with ethanoic acid. The method used in this study was the experimental method. The results showed acid modified starch yield was 18%, with the color characteristics of L*: 96.38 ± 0.82; a*: -0.70±0.02 b*: 2.70±0.03 C: 2.79±0.02. Native starch yield was 16%, with the color characteristics of L*: 93.55 ± 0.91; a*: -0.86±0.06 b*: 2.93±0.04 C: 3.05±0.03. The conclusion of this study was modified starch of Cilembu sweet potato using ethanoic acid have higher yield and more white bright than native starch.

  10. Annealing properties of potato starches with different degrees of phosphorylation

    Muhrbeck, Per; Svensson, E


    Changes in the gelatinization temperature interval and gelatinization enthalpy with annealing time at 50 degrees C were followed for a number of potato starch samples, with different degrees of phosphorylation, using differential scanning calorimetry. The gelatinization temperature increased with...... and crystalline structure of amylopectin helices. (C) 1997 Elsevier Science Ltd....

  11. Fluidization of potato starch in a stirred vibrating fluidized bed

    Kuipers, N.J M; Stamhuis, Eize; Beenackers, A.A C M


    A novel gas-solid reactor for cohesive C-powders such as potato starch is introduced, designed and characterized, the so-called stirred vibrating fluidized bed. The effects of a sinusoidal vibration of the gas distributor and/or stirring of the bed are investigated. The fluidization index, bed expan

  12. Fluidization of potato starch in a stirred vibrating fluidized bed

    Kuipers, N.J M; Stamhuis, Eize; Beenackers, A.A C M

    A novel gas-solid reactor for cohesive C-powders such as potato starch is introduced, designed and characterized, the so-called stirred vibrating fluidized bed. The effects of a sinusoidal vibration of the gas distributor and/or stirring of the bed are investigated. The fluidization index, bed

  13. Experiment 9: ASTROCULTURE: Growth and Starch Accumulation of Potato Tuber

    Tibbitts, Theodore W.; Brown, Christopher S.; Croxdale, Judith G.; Wheeler, Raymond M.


    Potato explants (leaf, small stem section, and axillary bud) flown on STS-73 developed tubers of 1.5 cm diameter and 1.7 g mass during the 16-day period of space flight. The experiment was undertaken in the ASTROCULTURE(TM) experiment package under controlled temperature, humidity, lighting, and carbon dioxide concentrations. The tubers that formed in the explant system under microgravity had the same gross morphology, the same anatomical configuration of cells and tissues, and the same sizes, shapes, and surface character of starch granules as tubers formed in a 1 g environment. The total accumulation of starch and other energy containing compounds was similar in space flight and ground control tubers. Enzyme activity of starch synthase, starch phosphorylase, and total hydrolase was similar in space flight and ground controls, but activity of ADP-glucose pyrophosphorylase was reduced in the space flight tuber tissue. This experiment documented that potatoes will metabolize and accumulate starch as effectively in space flight as on the ground. Thus, this data provides the potential for effective utilization of potatoes in life support systems of space bases.

  14. Comparison of waxy and normal potato starch remaining granules after chemical surface gelatinization: pasting behavior and surface morphology.

    Huang, Junrong; Chen, Zhenghong; Xu, Yalun; Li, Hongliang; Liu, Shuxing; Yang, Daqing; Schols, Henk A


    To understand the contribution of granule inner portion to the pasting property of starch, waxy potato starch and two normal potato starches and their acetylated starch samples were subjected to chemical surface gelatinization by 3.8 mol/L CaCl2 to obtain remaining granules. Native and acetylated, original and remaining granules of waxy potato starch had similar rapid visco analyzer (RVA) pasting profiles, while those of two normal potato starches behaved obviously different from each other. All remaining granules had lower peak viscosity than the corresponding original granules. Contribution of waxy potato starch granule's inner portion to the peak viscosity was significant more than those of normal potato starches. The shell structure appearing on the remaining granule surface for waxy potato starch was smoother and thinner than that for normal potato starches as observed by scanning electron microscopy, indicating a more regular structure of shell and a more ordered packing of shell for waxy potato starch granules. The blocklet size of waxy potato starch was smaller and more uniform than those of normal potato starches as shown by atomic force microscopy images of original and remaining granules. In general, our results provided the evidence for the spatial structure diversity between waxy and normal potato starch granules: outer layer and inner portion of waxy potato starch granule had similar structure, while outer layer had notably different structure from inner portion for normal potato starch granule.

  15. Preparation of potato starch microfibers obtained by electro wet spinning

    Cárdenas, W.; Gómez-Pachon, E. Y.; Muñoz, E.; Vera-Graziano, R.


    Starch is one of the most abundant biopolymer in nature. It has been primarily used as a thickener in the food industry. Starch is found in greater amounts in the potato tubers, which is one of the largest food productions in the region of Boyacá-Colombia. Thus, potatoes are a viable source of starch. The main objective of this study is the preparation and characterization of native starch's microfiber by electro wet-spinning technique. The parameters that were changed for each treatment were as follows: the amount of potential applied to the solution, the distance between the needle and the collector and the rate of injection of the solution in order to determine the physical and chemical properties of the membranes, conformed by potatoes starch microfiber. Diverse instrumental analysis techniques were applied. They were: Scanning Electron Microscopy (SEM) to determine the morphologies and diameters of microfibers, Fourier Transform Infrared Spectroscopy (FTIR) to determine the chemical changes, Thermogravimetric Analysis (TGA) and Differential Calorimetry Scanning (DSC) to obtain the thermal transitions and the temperatures of useful. The microfibers were analysed in order to determine their structural properties and thus define the range of application. In conclusion, potatoes starch microfibers were obtained with average diameters of 15, 17, 23 and 25 micrometres, besides the fibers presented a degradation temperature of 304 °C, indicating that fibers are available with diameters of small scale, with good thermal properties. This study will enable the implementation of the microfibers to obtain bio packaging for food products and other applications.

  16. Effects of charge-carrying amino acids on the gelatinization and retrogradation properties of potato starch.

    Chen, Wenting; Zhou, Hongxian; Yang, Hong; Cui, Min


    The objective of this study was to evaluate the effects of charge-carrying amino acids (lysine (Lys), arginine (Arg), aspartic acid (Asp) and glutamic acid (Glu)) on the gelatinization and retrogradation properties of potato starch. Acidic amino acids (Asp and Glu) showed a decreasing trend in swelling power and granule size of potato starch, but increased amylose leaching and gelatinization temperature. Alkaline amino acid (Arg) showed an increasing trend in swelling power and granule size of potato starch, but decreasing amylose leaching and gelatinization temperature. Lys had no effect on the swelling power of potato starch, except at a high content (0.2 mol/kg). Like other two acidic amino acids, Lys also increased gelatinization temperature. Moreover, the addition of alkaline amino acids (Arg) decreased syneresis value of potato starch but acidic amino acids (Asp and Glu) increased it. Compared to Arg, the syneresis of potato starch with Lys was similar to that of its native starch.

  17. Electron microscopy and composition of raw acorn starch in relation to in vivo starch digestibility.

    Cappai, Maria Grazia; Alesso, Giuseppe Andrea; Nieddu, Giuseppa; Sanna, Marina; Pinna, Walter


    The structure and composition of starch play an important role as co-factors affecting raw starch digestibility: such features were investigated in raw acorn starch from the most diffused oak trees in the Mediterranean basin. A total of 620 whole ripe acorns from Holm (Quercus ilex L., n = 198), Downy (Quercus pubescens Willd., n = 207) and Cork (Quercus suber L., n = 215) oaks sampled on the Sardinia Isle (40° 56' 0'' N; 9° 4' 0'' E; 545 m above the mean sea level) in the same geographical area, were analyzed for their chemical composition. The starch contents ranged between 51.2% and 53.5% of dry matter. The starch granules displayed a spheroid/ovoid and cylindrical shape; on scanning electron microscopic (SEM) analyses, a bimodal distribution of starch granule size was observed both for Holm and Cork oak acorns, whereas the starch granules of Downy oak acorns showed diameters between 10.2 and 13.8 μm. The specific amylose to amylopectin ratio of acorn starch was 25.8%, 19.5% and 34.0% in the Holm, Downy and Cork oaks, respectively. The (13)C Nuclear Magnetic Resonance (NMR) signal analysis displayed a pivotal spectrum for the identification of the amylose peaks in raw acorn starch, as a basis for the amylose to amylopectin ratio determination.

  18. Evaluation of starch noodles made from three typical Chinese sweet-potato starches

    Chen, Z.; Sagis, L.M.C.; Legger, A.; Linssen, J.P.H.; Schols, H.A.; Voragen, A.G.J.


    The physical properties of starches from 3 typical Chinese sweet potato varieties (SuShu2, SuShu8, and XuShu18) were studied in relation to their noodle-making performance. The starch gel properties of SuShu2 differed from those of SuShu8 and XuShu18. As determined by both instrumental and sensory a

  19. Precision breeding for novel starch variants in potato.

    Muth, Jost; Hartje, Stefanie; Twyman, Richard M; Hofferbert, Hans-Reinhard; Tacke, Eckhard; Prüfer, Dirk


    Potato can be used as a source of modified starches for culinary and industrial processes, but its allelic diversity and tetraploid genome make the identification of novel alleles a challenge, and breeding such alleles into elite lines is a slow and difficult process. An efficient and reliable strategy has been developed for the rapid introduction and identification of new alleles in elite potato breeding lines, based on the ethylmethanesulphonate mutagenesis of dihaploid seeds. Using the granule-bound starch synthase I gene (waxy) as a model, a series of point mutations that potentially affect gene expression or enzyme function was identified. The most promising loss-of-function allele (waxy(E1100)) carried a mutation in the 5'-splice donor site of intron 1 that caused mis-splicing and protein truncation. This was used to establish elite breeding lineages lacking granule-bound starch synthase I protein activity and producing high-amylopectin starch. This is the first report of rapid and efficient mutation analysis in potato, a genetically complex and vegetatively propagated crop.


    A. Sh. Mannapova; Z. A. Kanarskaya; A. V. Kanarskii; G. P. Shuvaeva


    Here in this article the justification of expediency of enzyme resistant starch use in therapeutic food products is presented . Enzyme resistant starch is capable to resist to enzymatic hydrolysis in a small intestine of a person, has a low glycemic index, leads to decrease of postprandial concentration of glucose, cholesterol, triglycerides in blood and insulin reaction, to improvement of sensitivity of all organism to insulin, to increase in sense of fulness and to reduction of adjournment ...

  1. High pressure impact on changes in potato starch granules

    Słomińska Lucyna


    Full Text Available Air dry potato starch (84.9% d.s. was subjected to pressurizing under the pressure of 50, 100, 250, 500, 750, 1000 and 2000 MPa for 1 h. The physical properties of pressurized starch, such as morphology, surface and crystalline structure, gelatinization parameters, were studied by means of scanning and atomic force microscopy (SEM/AFM, X-ray diffraction (X-ray, differential scanning calorimetry (DSC. The susceptibility to the amylolytic enzyme (α-amylase was also measured. Application of pressure in the range of 50–2000 MPa results in an increase in the compressed potato starch bulk density, change in the contours of the granules from oval to polyhedral, increase in the roughness of the granule surface, vanishing of the X-ray reflexes generated by the orthogonal structure and weakening of the reflexes generated by the hexagonal structure, lowering of the enthalpy of starch gelatinization, and the enhancement of hydrolytic susceptibility of starch granules to the amylolytic enzyme.

  2. Irradiated gelatin-potato starch blends: evaluation of physicochemical properties

    Inamura, Patricia Y.; Regis, Wellington; Mastro, Nelida L., E-mail: [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)


    Macromolecular polysaccharides of large chains as starch can interlace with gelatin modifying their mechanical resistance. In this work, biodegradable bovine gelatin-potato starch blends films were developed using glycerol as plasticizer. Three formulations of gelatin/starch proportions (w/w) were used (1:0; 3:1; 1:1) and casting was the chosen method. The dried samples were then submitted to ionizing radiation coming from an electron beam (EB) accelerator with doses of 20 and 40 kGy, at room temperature, in the presence of air. Mechanical properties such as puncture strength and elongation at break were measured. Color measurements, water absorption, moisture, and film solubility were assessed. The results showed that starch addition to films based on gelatin as well as irradiation affected physical and structural properties of the films. Although the increase of starch content in the mixture led to decrease of the puncture force even in samples irradiated with the higher dose, there was a decrease of water absorption of films with the increase of the dose, and also by the higher starch content. Samples irradiated at 20 kGy presented higher moisture and film solubility. The methodology developed in this paper can be applied to other composite systems to establish the best protein:starch ratio, and the contribution of the radiation crosslinking in each specific case. (author)

  3. Characterization of banana, potato, and rice starch blends for their physicochemical and pasting properties

    Ritika B. Yadav


    Full Text Available The properties of blends of banana, potato, and rice starches were studied to assess their suitability as an alternate for chemically modified starches. The blends of banana, potato, and rice starches were prepared in the respective ratio of 1:3:2, 3:2:1, and 2:1:3. The blend with higher proportion of banana and rice starches (BPR-213 showed highest water absorption capacity and oil absorption capacity. The blend with higher proportion of banana starch (BPR-321 showed highest swelling power at 95°C but lowest water solubility at 95°C among other starch blends. The blend made with higher amount of potato starch (BPR-132 had significantly higher paste clarity than other blends (p < 0.05. The potato starch had significantly higher least gelation concentration than all other starches and their blends (p < 0.05. The banana starch and blend with highest proportion of banana starch (BPR-321 showed significantly lesser percent syneresis and thus highest freeze–thaw stability. Potato starch as well as it blends with greater amount of potato starch (BPR-132 showed highest value for peak viscosity, hot paste viscosity, and final viscosity than other blends.

  4. Efficient production of pullulan by Aureobasidium pullulans grown on mixtures of potato starch hydrolysate and sucrose.

    An, Chao; Ma, Sai-Jian; Chang, Fan; Xue, Wen-Jiao

    Pullulan is a natural exopolysaccharide with many useful characteristics. However, pullulan is more costly than other exopolysaccharides, which limits its effective application. The purpose of this study was to adopt a novel mixed-sugar strategy for maximizing pullulan production, mainly using potato starch hydrolysate as a low-cost substrate for liquid-state fermentation by Aureobasidium pullulans. Based on fermentation kinetics evaluation of pullulan production by A. pullulans 201253, the pullulan production rate of A. pullulans with mixtures of potato starch hydrolysate and sucrose (potato starch hydrolysate:sucrose=80:20) was 0.212h(-1), which was significantly higher than those of potato starch hydrolysate alone (0.146h(-1)) and mixtures of potato starch hydrolysate, glucose, and fructose (potato starch hydrolysate:glucose:fructose=80:10:10, 0.166h(-1)) with 100gL(-1) total carbon source. The results suggest that mixtures of potato starch hydrolysate and sucrose could promote pullulan synthesis and possibly that a small amount of sucrose stimulated the enzyme responsible for pullulan synthesis and promoted effective potato starch hydrolysate conversion effectively. Thus, mixed sugars in potato starch hydrolysate and sucrose fermentation might be a promising alternative for the economical production of pullulan.

  5. Slowly digestible starch from heat-moisture treated waxy potato starch: preparation, structural characteristics, and glucose response in mice

    Heat-moisture treatment (HMT) was optimized to increase the formation of slowly digestible starch (SDS) in waxy potato starch, and the structural and physiological properties of this starch were investigated. A maximum SDS content (41.8%) consistent with the expected value (40.1%) was obtained after...

  6. Engineering Yarrowia lipolytica to produce biodiesel from raw starch.

    Ledesma-Amaro, Rodrigo; Dulermo, Thierry; Nicaud, Jean Marc


    In the last year, the worldwide concern about the abuse of fossil fuels and the seeking for alternatives sources to produce energy have found microbial oils has potential candidates for diesel substitutes. Yarrowia lipolytica has emerged as a paradigm organism for the production of bio-lipids in white biotechnology. It accumulates high amounts of lipids from glucose as sole carbon sources. Nonetheless, to lower the cost of microbial oil production and rival plant-based fuels, the use of raw and waste materials as fermentation substrate is required. Starch is one of the most abundant carbohydrates in nature and it is constituted by glucose monomers. Y. lipolytica lacks the capacity to breakdown this polymer and thus expensive enzymatic and/or physical pre-treatments are needed. In this work, we express heterologous alpha-amylase and glucoamylase enzymes in Y. lipolytica. The modified strains were able to produce and secrete high amounts of active form of both proteins in the culture media. These strains were able to grow on starch as sole carbon source and produce certain amount of lipids. Thereafter, we expressed both enzymes in an engineered strain able to overaccumulate lipids. This strain was able to produce up to 21 % of DCW as fatty acids from soluble starch, 5.7 times more than the modified strain in the wild-type background. Media optimization to increase the C/N ratio to 90 increased total lipid content up to 27 % of DCW. We also tested these strains in industrial raw starch as a proof of concept of the feasibility of the consolidated bioprocess. Lipid production from raw starch was further enhanced by the expression of a second copy of each enzyme. Finally, we determined in silico that the properties of a biodiesel produced by this strain from raw starch would fit the established standards. In this work, we performed a strain engineering approach to obtain a consolidated bioprocess to directly produce biolipids from raw starch. Additionally, we proved

  7. Genome-wide analysis of starch metabolism genes in potato (Solanum tuberosum L.).

    Van Harsselaar, Jessica K; Lorenz, Julia; Senning, Melanie; Sonnewald, Uwe; Sonnewald, Sophia


    Starch is the principle constituent of potato tubers and is of considerable importance for food and non-food applications. Its metabolism has been subject of extensive research over the past decades. Despite its importance, a description of the complete inventory of genes involved in starch metabolism and their genome organization in potato plants is still missing. Moreover, mechanisms regulating the expression of starch genes in leaves and tubers remain elusive with regard to differences between transitory and storage starch metabolism, respectively. This study aimed at identifying and mapping the complete set of potato starch genes, and to study their expression pattern in leaves and tubers using different sets of transcriptome data. Moreover, we wanted to uncover transcription factors co-regulated with starch accumulation in tubers in order to get insight into the regulation of starch metabolism. We identified 77 genomic loci encoding enzymes involved in starch metabolism. Novel isoforms of many enzymes were found. Their analysis will help to elucidate mechanisms of starch biosynthesis and degradation. Expression analysis of starch genes led to the identification of tissue-specific isoenzymes suggesting differences in the transcriptional regulation of starch metabolism between potato leaf and tuber tissues. Selection of genes predominantly expressed in developing potato tubers and exhibiting an expression pattern indicative for a role in starch biosynthesis enabled the identification of possible transcriptional regulators of tuber starch biosynthesis by co-expression analysis. This study provides the annotation of the complete set of starch metabolic genes in potato plants and their genomic localizations. Novel, so far undescribed, enzyme isoforms were revealed. Comparative transcriptome analysis enabled the identification of tuber- and leaf-specific isoforms of starch genes. This finding suggests distinct regulatory mechanisms in transitory and storage starch

  8. Sugar Profile, Mineral Content, and Rheological and Thermal Properties of an Isomerized Sweet Potato Starch Syrup.

    Dominque, Brunson; Gichuhi, Peter N; Rangari, Vijay; Bovell-Benjamin, Adelia C


    Currently, corn is used to produce more than 85% of the world's high fructose syrup (HFS). There is a search for alternative HFS substrates because of increased food demand and shrinking economies, especially in the developing world. The sweet potato is a feasible, alternative raw material. This study isomerized a high glucose sweet potato starch syrup (SPSS) and determined its sugar profile, mineral content, and rheological and thermal properties. Rheological and thermal properties were measured using a rheometer and DSC, respectively. Sweet potato starch was hydrolyzed to syrup with a mean fructose content of 7.6 ± 0.4%. The SPSS had significantly higher (P SPSS acted as a non-Newtonian, shear-thinning liquid in which the viscosity decreased as shear stress increased. Water loss temperature of the SPSS continually decreased during storage, while pancake and ginger syrups' peak water loss temperature decreased initially and then increased. Further and more detailed studies should be designed to further enhance the fructose content of the syrup and observe its stability beyond 70 days. The SPSS has the potential to be used in human food systems in space and on Earth.

  9. Sugar Profile, Mineral Content, and Rheological and Thermal Properties of an Isomerized Sweet Potato Starch Syrup

    Brunson Dominque


    Full Text Available Currently, corn is used to produce more than 85% of the world’s high fructose syrup (HFS. There is a search for alternative HFS substrates because of increased food demand and shrinking economies, especially in the developing world. The sweet potato is a feasible, alternative raw material. This study isomerized a high glucose sweet potato starch syrup (SPSS and determined its sugar profile, mineral content, and rheological and thermal properties. Rheological and thermal properties were measured using a rheometer and DSC, respectively. Sweet potato starch was hydrolyzed to syrup with a mean fructose content of 7.6±0.4%. The SPSS had significantly higher (P<0.05 mineral content when compared to commercial ginger and pancake syrups. During 70 days of storage, the SPSS acted as a non-Newtonian, shear-thinning liquid in which the viscosity decreased as shear stress increased. Water loss temperature of the SPSS continually decreased during storage, while pancake and ginger syrups’ peak water loss temperature decreased initially and then increased. Further and more detailed studies should be designed to further enhance the fructose content of the syrup and observe its stability beyond 70 days. The SPSS has the potential to be used in human food systems in space and on Earth.

  10. Characteristics of raw starch degrading alpha-amylase from Bacillus aquimaris MKSC 6.2 associated with soft coral Sinularia sp.

    Puspasari, Fernita; Nurachman, Zeily; Noer, Achmad Saefuddin; Radjasa, Ocky Karna; van der Maarel, Marc J. E. C.; Natalia, Dessy

    Partially purified alpha-amylase from Bacillus aquimaris MKSC 6.2, a bacterium isolated from a soft coral Sinularia sp., Merak Kecil Island, West Java, Indonesia, showed an ability to degrade raw corn, rice, sago, cassava, and potato starches with adsorption percentage in the range of 65-93%. Corn

  11. Characteristics of raw starch degrading alpha-amylase from Bacillus aquimaris MKSC 6.2 associated with soft coral Sinularia sp.

    Puspasari, Fernita; Nurachman, Zeily; Noer, Achmad Saefuddin; Radjasa, Ocky Karna; van der Maarel, Marc J. E. C.; Natalia, Dessy


    Partially purified alpha-amylase from Bacillus aquimaris MKSC 6.2, a bacterium isolated from a soft coral Sinularia sp., Merak Kecil Island, West Java, Indonesia, showed an ability to degrade raw corn, rice, sago, cassava, and potato starches with adsorption percentage in the range of 65-93%. Corn h

  12. Structural characteristics and glucose response in mice of potato starch modified by hydrothermal treatments

    The structural properties and digestibility of slowly digestible The structural properties and digestibility of slowly digestible hydrothermally treated potato starch (SDS) were investigated. The potato starch with 20, 30 or 40% moisture content was heated at 100 °C for 30 min, and then kept at 30 °...

  13. Potato powders prepared by successive cooking-process depending on resistant starch content affect the intestinal fermentation in rats.

    Kawakami, Sakura; Han, Kyu-Ho; Araki, Takahiro; Ohba, Kiyoshi; Wakabayashi, Tatsuya; Shimada, Kenichiro; Fukushima, Michihiro


    The effects of resistant starch (RS) in dry potato powders prepared by various processes on intestinal fermentation in rats were assessed. Rats were fed raw potato powder (RP), blanched potato powder (BP), steamed potato powder (SP), or drum-dried potato powder (DP) for 4 weeks. The cecal RS content was significantly higher in the RP group than in the control diet (CN) group and other dry potato powder groups. Cecum pH was significantly lower in the RP group compared to the CN group, and was also significantly lower than that in the SP, BP, and DP groups. Lactic acid bacteria levels in the RP group were significantly higher than those in the CN group, and levels in the SP group also increased relative to the control group. Lactobacillus levels in the RP group were higher than in the CN and other dry potato powder groups. Cecal short-chain fatty acid (SCFA) concentrations in the RP group followed by the SP group exhibited significantly higher levels relative to the control levels. Dry potato powders containing RS produced during the cooking process may represent a useful food material that increases intestinal concentrations of SCFA and enhances the growth of certain lactic acid bacteria.

  14. Effects of chitin nano-whiskers on the gelatinization and retrogradation of maize and potato starches.

    Ji, Na; Liu, Chengzhen; Zhang, Shuangling; Yu, Jing; Xiong, Liu; Sun, Qingjie


    Starch is very prone to retrogradation after gelatinization. Inhibition of starch retrogradation has been an important factor in improving the quality of food. For the first time, we investigated the effect of nano-materials, represented by chitin nano-whiskers (CNWs), on the short- and long-term retrogradation of maize and potato starches. Rapid Visco-Analyser results showed that the addition of CNWs significantly decreased the setback values of maize and potato starches, which suggested that CNWs could retard the short-term retrogradation of starch. Differential scanning calorimetry and X-ray diffraction results showed that the percentage of retrogradation of maize and potato starches significantly decreased (Pretrogradation. The CNWs could be used as a new inhibitor of starch retrogradation to develop starch-based food with longer shelf life.

  15. Production of a raw starch saccharifying amylase byBacillus alvei grown on different agricultural substrates.

    Achi, O K; Nijoku-Obi, A N


    Maximum activity of the amylase ofBacillus alvei was attained after growth of the organism on sorghum starch. Rice, corn, yam, cassava and potato starch gave high enzyme activities as did soluble starch. Glucose, maltose and glycerol were less effective. Optimum conditions for both growth and enzyme production were pH 6.8 at 40°C.

  16. Functional characterization on native starch of Peruvian native potatoes (Solanum phureja)

    Martínez, P.; Málaga, A.; Betalleluz, I.; Ibarz, A; C. Velezmoro


    There are many varieties of native potatoes grown in different regions of Peru, usually for farmers´ consumption. However, the possibility of a commercial use has led this work in order to give them added value. To evaluate the possibility of use of native starch from these potatoes, as an ingredient in the food industry, it was presented as objective to determine the physicochemical, functional and viscoelastic native potato starches obtained from Pampacorral properties (Cuzco, Peru): Puka A...

  17. Comparison of waxy and normal potato starch remaining granules after chemical surface gelatinization: Pasting behavior and surface morphology

    Huang, J.; Chen Zenghong,; Xu, Yalun; Li, Hongliang; Liu, Shuxing; Yang, Daqing; Schols, H.A.


    o understand the contribution of granule inner portion to the pasting property of starch, waxy potato starch and two normal potato starches and their acetylated starch samples were subjected to chemical surface gelatinization by 3.8 mol/L CaCl2 to obtain remaining granules. Native and acetylated, or

  18. Comparison of waxy and normal potato starch remaining granules after chemical surface gelatinization: Pasting behavior and surface morphology

    Huang, J.; Chen Zenghong,; Xu, Yalun; Li, Hongliang; Liu, Shuxing; Yang, Daqing; Schols, H.A.


    o understand the contribution of granule inner portion to the pasting property of starch, waxy potato starch and two normal potato starches and their acetylated starch samples were subjected to chemical surface gelatinization by 3.8 mol/L CaCl2 to obtain remaining granules. Native and acetylated,

  19. Discovery of a low-glycaemic index potato and relationship with starch digestion in vitro.

    Ek, Kai Lin; Wang, Shujun; Copeland, Les; Brand-Miller, Jennie C


    Potatoes are usually a high-glycaemic index (GI) food. Finding a low-GI potato and developing a screening method for finding low-GI cultivars are both health and agricultural priorities. The aims of the present study were to screen the commonly used and newly introduced cultivars of potatoes, in a bid to discover a low-GI potato, and to describe the relationship between in vitro starch digestibility of cooked potatoes and their in vivo glycaemic response. According to International Standard Organisation (ISO) guidelines, seven different potato cultivars were tested for their GI. In vitro enzymatic starch hydrolysis and chemical analyses, including amylose content analysis, were carried out for each potato cultivar, and correlations with the respective GI values were sought. The potato cultivars had a wide range of GI values (53-103). The Carisma cultivar was classified as low GI and the Nicola cultivar (GI = 69) as medium GI and the other five cultivars were classified as high GI according to ISO guidelines. The GI values were strongly and positively correlated with the percentage of in vitro enzymatic hydrolysis of starch in the cooked potatoes, particularly with the hydrolysis percentage at 120 min (r 0·91 and P starch content was not correlated with either in vitro starch digestibility or GI. The findings suggest that low-GI potato cultivars can be identified by screening using a high-throughput in vitro digestion procedure, while chemical composition, including amylose and fibre content, is not indicative.

  20. Testing properties of potato starch from different scales of isolations - A ringtest

    Wischmann, Bente; Ahmt, T.; Bandsholm, O.


    Five different procedures were used to isolate potato starch from the same batch at three different scales in order to analyse what influence scaling up of the starch process had on the starch physical/chemical properties. Common to the five isolation processes was the steps of washing and macera...

  1. Phenotypic and genotypic characterization of an amylose-free starch mutant of the potato

    Jacobsen, E.; Hovenkamp-Hermelink, J.H.M; KRIJGSHELD, HT; NIJDAM, H; Pijnacker, L.P.; Witholt, B.; Feenstra, W.J.


    The amylose-free (amf) potato mutant 86.040 has been characterized phenotypically and genotypically . Not only storage starch in tubers and metabolic starch in leaves but also starch in cells with specific functions, such as columella cells in the root cap and guard cells of stomata, was

  2. Enzymatic degradation of granular potato starch by Microbacterium aurum strain B8.A

    Sarian, Fean D.; van der Kaaij, Rachel M.; Kralj, Slavko; Wijbenga, Dirk-Jan; Binnema, Doede J.; van der Maarel, Marc J. E. C.; Dijkhuizen, Lubbert


    Microbacterium aurum strain B8.A was isolated from the sludge of a potato starch-processing factory on the basis of its ability to use granular starch as carbon- and energy source. Extracellular enzymes hydrolyzing granular starch were detected in the growth medium of M. aurum B8.A, while the type s

  3. Structural characteristics of slowly digestible starch and resistant starch isolated from heat-moisture treated waxy potato starch.

    Lee, Chang Joo; Moon, Tae Wha


    The objective of this study was to investigate the structural characteristics of slowly digestible starch (SDS) and resistant starch (RS) fractions isolated from heat-moisture treated waxy potato starch. The waxy potato starch with 25.7% moisture content was heated at 120°C for 5.3h. Scanning electron micrographs of the cross sections of RS and SDS+RS fractions revealed a growth ring structure. The branch chain-length distribution of debranched amylopectin from the RS fraction had a higher proportion of long chains (DP ≥ 37) than the SDS+RS fraction. The X-ray diffraction intensities of RS and SDS+RS fractions were increased compared to the control. The SDS+RS fraction showed a lower gelatinization enthalpy than the control while the RS fraction had a higher value than the SDS+RS fraction. In this study we showed the RS fraction is composed mainly of crystalline structure and the SDS fraction consists of weak crystallites and amorphous regions.

  4. Effect of Hydroxypropylation on Functional Properties of Different Cultivars of Sweet Potato Starch in Sri Lanka

    Senanayake, Suraji; Gunaratne, Anil; Ranaweera, K. K. D. S.; Bamunuarachchi, Arthur


    Starches obtained from different cultivars of sweet potatoes commonly consumed in Sri Lanka, were chemically modified with hydroxypropyl substitution, to analyze the changes in the physicochemical properties. Significant changes (P gelatinization and retrogradation enthalpies as well as gelatinization temperature were observed for derivatized starches compared to the native starch. Low levels of pasting stability with increased levels of breakdown and reduced cold paste viscosity were observed in the hydroxypropylated starch samples except for the Malaysian cultivar (S5). Chemically modified starch gels stored under cold storage did not show a syneresis for two weeks in the cycle and the frozen storage showed much improved stability in the starch gels within the four-week cycle. Chemical modification of sweet potato starch with hydroxyl propyl substitution can enhance the functional characteristics of the native starch which will improve its potential application in the food industry. PMID:26904619

  5. Starch digestibility and predicted glycemic index of fried sweet potato cultivars


    Background: Sweet potato (Ipomoea batatas L.) is a very rich source of starch. There is increased interest in starch digestibility and the prevention and management of metabolic diseases.Objective: The aim of this study was to evaluate the levels of starch fractions and predicted glycemic index of different cultivars of sweet potato. Material and Method: French fries produced from five cultivars of sweet potato (‘Ginseng Red’, ‘Beauregard’, ‘White Travis’, ‘Georgia Jet clone #2010’ and ‘G...

  6. Enzymatic degradation of granular potato starch by Microbacterium aurum strain B8.A.

    Sarian, Fean D; van der Kaaij, Rachel M; Kralj, Slavko; Wijbenga, Dirk-Jan; Binnema, Doede J; van der Maarel, Marc J E C; Dijkhuizen, Lubbert


    Microbacterium aurum strain B8.A was isolated from the sludge of a potato starch-processing factory on the basis of its ability to use granular starch as carbon- and energy source. Extracellular enzymes hydrolyzing granular starch were detected in the growth medium of M. aurum B8.A, while the type strain M. aurum DSMZ 8600 produced very little amylase activity, and hence was unable to degrade granular starch. The strain B8.A extracellular enzyme fraction degraded wheat, tapioca and potato starch at 37 °C, well below the gelatinization temperature of these starches. Starch granules of potato were hydrolyzed more slowly than of wheat and tapioca, probably due to structural differences and/or surface area effects. Partial hydrolysis of starch granules by extracellular enzymes of strain B8.A resulted in large holes of irregular sizes in case of wheat and tapioca and many smaller pores of relatively homogeneous size in case of potato. The strain B8.A extracellular amylolytic system produced mainly maltotriose and maltose from both granular and soluble starch substrates; also, larger maltooligosaccharides were formed after growth of strain B8.A in rich medium. Zymogram analysis confirmed that a different set of amylolytic enzymes was present depending on the growth conditions of M. aurum B8.A. Some of these enzymes could be partly purified by binding to starch granules.

  7. Rheological, pasting, thermal and retrogradation properties of octenyl succinic anhydride modified potato starch

    Chuin WON

    Full Text Available Abstract The objective of the present study was to investigate the rheological, pasting, and thermal properties of octenyl succinic anhydrate (OSA-modified potato starch. Potato starch was modified using different concentrations of OSA (0, 1, 3, and 5%, v/v. The degree of substitution (DS for the OSA-modified starch ranged from 0.0012 to 0.0055. The amylose leaching values of native and OSA-modified potato starch with different DS levels were in the range of 47.09-87.32%. The gel strength values of the OSA-modified starch were lower than those of native potato starch. Rapid Visco Analyzer data showed that peak, hot pasting, final and setback viscosities of the native starch decreased after OSA modification. Dynamic shear rheological tests, conducted at 4 °C, indicated that OSA-modified potato starch had weak gel-like behavior with the storage moduli (G' higher than the loss moduli (G” over most of the frequency ranges (0.63-63.8 rad·s-1.

  8. Changes in the mechanical properties of thermoplastic potato starch in relation with changes in B-type crystallinity

    Vliegenthart, J.F.G.; Soest, J.J.G. van; Hulleman, S.H.D.; Wit, D. de


    The influence of crystallization on the stress-strain behaviour of thermoplastic potato starch has been monitored. Potato starch has been processed by extrusion with glycerol and water added as plasticizers. The thermoplastic starch consists of a molecular network of semicrystalline amylose and amyl

  9. The effects of electrolysis at room temperature on retrogradation of sweet potato starch.

    Xijun, Lian; Kunsheng, Zhang; Qingfeng, Luo; Xu, Zhang; Shuyi, Zhao


    The effects of electrolysis at room temperature on formation of sweet potato retrograded starch were studied by photographic method in the paper. The optimal parameters of electrolytic preparation of sweet potato retrograded starch were determined. The ratio between sweet potato starch and water was 10 g/100 mL with addition of NaCl 1.0 g/100 mL, pH value of the solution was 6.0 and the solution was electrolyzed for 30 min at 90 V at room temperature, then it was stored at 4°C for 24h after being autoclaved for 30 min at 120°C, the retrogradation rate of sweet potato starch at this condition was 33.1%, which is 138% higher than that of control group. Four possible reasons are put forward to explain the results.

  10. Kinetic study of enzymatic hydrolysis of potato starch

    Óscar Fernando Castellanos Domínguez


    Full Text Available This article describes the kinetic study of potato starch enzymatic hydrolysis using soluble enzymes (Novo Nordisk. Different assays divided into four groups were used: reaction time (with which it was possible to reduce the 48-72 hour duration reported in the literature to 16 hours with comparable productivity levels; selecting the set of enzymes to be used (different types were evaluated - BAN and Termamyl as alfa-amylases during dextrinisation stage, and AMG, Promozyme and Fungamyl for sacarification reaction- identifying those presenting the best performance during hydrolysis. Reaction conditions were optimised for the process's two stages (destrinisation and sacarification. Enzyme dose, calcium cofactor concentration, pH, temperature and agitation speed were studied for the first stage. Enzyme ratio, pH and agitation speed were studied for sacarification; the latter parameter reported values having no antecedents in the literature (60 rpm and 30 rpm for first and second reactions, respectively. Michaelis Menten kinetics were calculated once conditions had been optimised, varying substrate from 10-50% P/V, obtaining km and Vmax kinetic parameters for each reaction. A kinetic model was found according to local working conditions which was able to explain potato starch conversion to glucose syrup, achieving 96 dextrose equivalents by the end of the reaction, being well within the maximum range reported in the literature (94-98. Laboratory equipment was constructed prior to carrying out assays which was able to reproduce and improve the conditions reported in the literature, making it a useful, reliable tool for use in assays returning good results.

  11. Effect of citric acid concentration and hydrolysis time on physicochemical properties of sweet potato starches.

    Surendra Babu, Ayenampudi; Parimalavalli, Ramanathan; Rudra, Shalini Gaur


    Physicochemical properties of citric acid treated sweet potato starches were investigated in the present study. Sweet potato starch was hydrolyzed using citric acid with different concentrations (1 and 5%) and time periods (1 and 11 h) at 45 °C and was denoted as citric acid treated starch (CTS1 to CTS4) based on their experimental conditions. The recovery yield of acid treated starches was above 85%. The CTS4 sample displayed the highest amylose (around 31%) and water holding capacity its melting temperature was 47.66 °C. The digestibility rate was slightly increased for 78.58% for the CTS3 and CTS4. The gel strength of acid modified starches ranged from 0.27 kg to 1.11 kg. RVA results of acid thinned starches confirmed a low viscosity profile. CTS3 starch illustrated lower enthalpy compared to all other modified starches. All starch samples exhibited a shear-thinning behavior. SEM analysis revealed that the extent of visible degradation was increased at higher hydrolysis time and acid concentration. The CTS3 satisfied the criteria required for starch to act as a fat mimetic. Overall results conveyed that the citric acid treatment of sweet potato starch with 5% acid concentration and 11h period was an ideal condition for the preparation of a fat replacer.

  12. The Influence of Pair Spiral Extrusion Equipment on Thermoplastic Potato Starch

    Wang Qing-ning; Feng Hui-xia; Ye Qi-zhi


    Owing to contain a great deal of hydroxyl in Potato Starch, between the molecules and inside of molecules have very strong hydroxyl action. Thus, the liquate temperature is higher than disintegrate temperature, so it is difficult to process. Under the microscope, the microcosmic construction is a polar crystal molecule, and it appears globe predicament.To make the original potato starch into possession thermoplastic, we must make molecule of starch to change construct into amorphous state to form thermoplastic starch colophony. Besides auxiliary agent, shearing stress, temperature, time, pressure and hydrous quantity can affect the quality of starch thermoplastic too. The pair spiral extrude machine is used widely as the machines that are based of the pressure difference, and this extrude course may suffice require.Using the machine of pair spiral extrude of specific combination in the test of thermoplastic starch, the potato starch can be turned into thermoplastic starch of denaturalization preferably under auxiliary agent, shearing stress, temperature, pressure and the certain hydrous quantity.By the action of the technology process condition and the spiral combination, potato starch grains expand and fragmentate; hydroxyl bond cleave between and inside of molecules. Thus, crystallize state is changed into amorphous state. The transmutation of starch molecule property may be seen clearly from X diffraction chart and analyses of the construction property,By means of the denaturation, the crystal area of potato starch is broken,its crystallization degree is decreased,and its molecular chains are in amorphous state. The hydrogen bond among the molecular chain is broken or removed so that the starch structure is changed, making the starch thermoplastic.The processing of thermoplastic starch advances a higher requirement of ingredient water content, and technical conditions. A remodeled twin-screw extruder is used to create an environment to realize the condition of

  13. Melting properties and Lintnerisation of potato starch with different degrees of phosphorylation

    Wischmann, Bente; Adler-Nissen, Jens


    Lintner dextrins were prepared from size fractionated potato starch granules from two potato varieties (90BKG22 and Lady Rosetta) that contain high or low natural content of esterified phosphate, respectively. The time course of hydrolysis showed the typical two-phase kinetics, with a maximal....... The values of the melting temperatures (T-o, T-m and T-c) are positively correlated to the degree of phosphorylation of the starch dextrin fractions both before and after annealing....

  14. Effects of amino acids on the physiochemical properties of potato starch.

    Cui, Min; Fang, Ling; Zhou, Hongxian; Yang, Hong


    The objective of this study was to evaluate effects of different amino acid additives (phenylalanine (Phe), methionine (Met), lysine (Lys), arginine (Arg), aspartic acid (Asp) and glutamic acid (Glu)) on the physicochemical properties of potato starch gels. Charge-carrying amino acids (Lys, Arg, Asp and Glu) significantly decreased the swelling power, solubility, light transmittance, L(∗) value and gel strength of potato starch, but increased syneresis during freeze-thaw treatment, while neutral amino acids (Phe and Met) did not cause modifications in starch gels. During heating, potato starch with fortified charge-carrying amino acids showed a lower peak G' (storage modulus), when compared with Phe and Met. Results showed that charge-carrying amino acids could modify physicochemical properties and improve the nutritional values of starch-based products.

  15. Formation of a raw starch-hydrolyzing -amlyase by Clostridium 2021: effect of carbon sources

    Avendano, M.C.; Cornejo, I.


    Clostridium 2021 was found to produce -amylase effective at hydrolyzing raw starch. Of the carbohydrates examined, starch at 3% concentration was found to be the best carbon source for enzyme production. The products of -amylase action on starch were: maltose, glucose and higher dextrins.

  16. 紫薯淀粉理化性质的研究%Study on the Physicochemical Properties of Purple Sweet Potato Starch

    刘蒙; 曲智雅; 李小定; 范任海; 李杰; 张芸; 朱少华; 曲露; 王萌


    With starch extracted from purple sweet potato slag as raw material,this paper studied the chemical component,particle surface structure,crystal structure,gel texture,thermodynamic properties and rheological properties of the starch,comparing with the potato starch,corn starch and sweet potato starch at the same time.The main results and findings were summarized as follows:the starch content and amylose content of purple sweet potato starch were 98.78% and 19.74% respectively(dry weight) ;average particle size of the purple sweet potato starch granules was 17 μm,so the starch can be classified as medium size starch granule,and crystal form of type C;the starch gel showed a high springiness and chewiness,low hardness (3.095 × l02 g) and moderate viscosity (24.72 g · s) ; the gelatinization temperature scope was from 61.5 ℃ to 78.0 ℃,and the peak temperature was 72.6 ℃ ; the purple sweet potato slag starch paste was non-Newtonian fluid with yield stress.%以制得的紫薯淀粉为原料,研究了紫薯淀粉的化学组分、颗粒表面结构、结晶结构、凝胶质构、热力学性质和流变学特性,并与马铃薯淀粉、玉米淀粉和甘薯淀粉进行比较.结果显示:干基紫薯淀粉含量为98.78%,直链淀粉含量为19.74%;其淀粉颗粒平均粒径为17μm,属中粒淀粉,晶型为C型;淀粉凝胶弹性和咀嚼性高,硬度适中,为3.095×102 g,黏着性适中,为24.72 g·s;糊化温度范围为61.5℃到78.0℃,峰值温度为72.6℃;紫薯淀粉糊为有屈服应力的非牛顿型流体.

  17. Quality of shrimp analogue product as affected by addition of modified potato starch.

    Remya, S; Basu, S; Venkateshwarlu, G; Mohan, C O


    The present study was aimed to investigate the effects of addition of modified potato starch on the biochemical and textural properties of shrimp analogue/imitation shrimp, a popular value-added product prepared from surimi. Three batches of shrimp analogues were prepared with 0 % (NPS), 50 % (CPS) and 100 % (MPS) of modified starch incorporation and various quality attributes were monitored at regular intervals during frozen storage (-20 °C). Loss of myofibrillar protein was least for the shrimp analogue sample added with 100 % modified potato starch. The expressible moisture content of MPS (2.48 %) was less affected by long term storage compared to CPS (3.38 %) and NPS (3.99 %). During extended low temperature storage, the textural quality of sea food analogue was highly influenced by the type of starch added to it. The percentage of modified potato starch added to shrimp analogue significantly (p ≤ 0.05) affected its hardness and fracturability. MPS samples did not show significant changes in hardness during storage as compared to other two samples. Springiness of shrimp analogue increased 2.57, 1.5 and 1.77 times with the storage period for samples with NPS, CPS and MPS, respectively. Addition of modified potato starch improved the sensory quality and textural properties of shrimp analogue and reduced the quality degradation during frozen storage as compared to NPS which contained only native potato starch.

  18. Some characteristics of a raw starch digestion inhibitory factor from Aspergillus niger

    Towprayoon, S.; Saha, B.C.; Fujio, Yusaku; Ueda, Seinosuke


    The effect of an inhibitory factor (IF) from Aspergillus niger 19 on raw starch digestion by pure glucoamylase I of black Aspergillus, pure glucoamylase of Rhizopus niveus, bacterial ..cap alpha..-amylase, fungal ..cap alpha..-amylase and various combination was investigated. The IF caused higher inhibition of raw starch hydrolysis by the combined action of glucoamylase and fungal ..cap alpha..-amylase than of hydrolysis by the individual enzymes. A protein moiety of IF might play an active part in this inhibition phenomenon. The IF was found to starch granules, preventing hydrolysis by the enzymes, and caused decreased raw starch hydrolysis yields.

  19. Starch digestibility and predicted glycemic index of fried sweet potato cultivars

    Amaka Odenigbo


    Full Text Available Background: Sweet potato (Ipomoea batatas L. is a very rich source of starch. There is increased interest in starch digestibility and the prevention and management of metabolic diseases.Objective: The aim of this study was to evaluate the levels of starch fractions and predicted glycemic index of different cultivars of sweet potato. Material and Method: French fries produced from five cultivars of sweet potato (‘Ginseng Red’, ‘Beauregard’, ‘White Travis’, ‘Georgia Jet clone #2010’ and ‘Georgia Jet’ were used. The level of total starch (TS, resistant starch (RS, digestible starch (DS, and starch digestion index starch digestion index in the samples were evaluated. In vitro starch hydrolysis at 30, 90, and 120 min were determined enzymatically for calculation of rapidly digestible starch (RDS, predicted glycemic index (pGI and slowly digestible starch (SDS respectively. Results: The RS content in all samples had an inversely significant correlation with pGI (-0.52; P<0.05 while RDS had positive and significant influence on both pGI (r=0.55; P<0.05 and SDI (r= 0.94; P<0.01. ‘White Travis’ and ‘Ginseng Red’ had higher levels of beneficial starch fractions (RS and SDS with low pGI and starch digestion Index (SDI, despite their higher TS content. Generally, all the cultivars had products with low to moderate GI values. Conclusion: The glycemic index of these food products highlights the health promoting characteristics of sweet potato cultivars.

  20. Oxidized potato starch based thermoplastic films : Effect of combination of hydrophilic and amphiphilic plasticizers

    Niazi, Muhammad Bilal Khan; Broekhuis, Antonius A.


    Different combinations of hydrophilic (glycerol and water) and amphiphilic (isoleucine) plasticizers were studied in the production of thermoplastic starch (TPS) powders and films from oxidized potato starch. All powder samples had an irregular and shrivelled morphology. In all mixtures containing i

  1. Physicochemical properties of sweet potato starches and their application in noodle products

    Chen Zenghong,


    Starches isolated from 3 Chinese sweet potato varieties (XuShu18, SuShu2, and SuShu8) differed in granule size and particle size distribution as well as in protein, lipid and phosphorus contents but theamylosecontents were similar for these starches (19.3-20.0%). The pastin

  2. Physicochemical properties of potato and cassava starches and their mutants in relation to their structural properties

    Gomand, S.V.; Lamberts, L.; Visser, R.G.F.; Delcour, J.A.


    Physicochemical properties [swelling power (SP), pasting behaviour and retrogradation] of five wild type (wt), five amylose free (amf), four high-amylose (ha) potato starches (ps) and one wt and amf cassava starch (cs) were investigated. While swelling of wtps occurred in two phases, amfps showed a




    Kinetic results are presented for the hydroxypropylation of Potato starch with methyloxirane in aqueous solution. Reaction temperatures were varied from 303 to 362 K. Sodium hydroxide was used as a catalyst. The overall conversion rate of methyloxirane in alkaline starch solution is determined by th

  4. Supercritical carbon dioxide (scCO(2)) induced gelatinization of potato starch

    Muljana, Henky; Picchioni, Francesco; Heeres, Hero J.; Janssen, Leon P. B. M.


    The degree of gelatinization (DG) of potato starch after treatment with scCO(2) Was investigated. A broad range of experimental conditions were applied, including variations in temperature (50-90 degrees C), pressure (0.1-25 MPa), and the starch water content (16.2-40% wt/wt). Changes in the DG were

  5. Physicochemical properties of sweet potato starches and their application in noodle products

    Chen Zenghong,


    Starches isolated from 3 Chinese sweet potato varieties (XuShu18, SuShu2, and SuShu8) differed in granule size and particle size distribution as well as in protein, lipid and phosphorus contents but theamylosecontents were similar for these starches (19.3-20.0%). The pastin

  6. Antisense RNA mediated inhibition of granule-bound starch synthase gene expression in potato.

    Kuipers, G.J.


    Potato starch and its derivatives are widely used in several fields of application. The manufacturing of most products requires the modification of native starch with respect to, for example, viscosity and physical stability. In addition to the currently used physical, chemical and biochemical deriv

  7. Expression of an amylosucrase gene in potato results in larger starch granules with novel properties

    Huang, X.; Nazarian, F.; Vincken, J.P.; Ji, Q.; Visser, R.G.F.; Trindade, L.M.


    Main conclusion - Expression of amylosucrase in potato resulted in larger starch granules with rough surfaces and novel physico-chemical properties, including improved freeze–thaw stability, higher end viscosity, and better enzymatic digestibility. Starch is a very important carbohydrate in many foo

  8. Genotype by environment interaction effects on starch content and digestibility in potato (Solanum tuberosum L.).

    Bach, Stephanie; Yada, Rickey Y; Bizimungu, Benoit; Fan, Ming; Sullivan, J Alan


    Biochemically, starch is composed of amylose and amylopectin but can also be defined by its digestibility rates within the human intestinal tract, i.e., rapidly digested (RDS), slowly digested (SDS), or resistant (RS). The relative ratio of these starch components is the main contributor to differences in the glycemic index (GI) of carbohydrate sources. This study evaluated the digestible starch profile of 12 potato genotypes comprising elite breeding lines and commercial varieties in six environments, with the optimal profile defined as low RDS and high SDS. Genotype by environment interaction (GEI) analysis found significant (p = 0.05) genotypic and environmental effects for all digestibility rate components; however, interaction effects were only significant for SDS. Optimal starch profiles were identified for two genotypes, CV96044-3 and Goldrush. The desirable starch profile in these potato cultivars can be exploited in breeding programs for the improvement of starch profile and other important characteristics such as high yields and disease resistance.

  9. Stability and physicochemical properties of model salad dressings prepared with pregelatinized potato starch.

    Bortnowska, Grażyna; Balejko, Jerzy; Schube, Violetta; Tokarczyk, Grzegorz; Krzemińska, Natalia; Mojka, Katarzyna


    The effects of pregelatinized potato starch concentration (PSC) ranged from 0 to 5 wt% on the physical stability, color, rheological, textural, and sensory properties of model salad dressings prepared with 2 wt% dried egg yolk (DEY) or sodium caseinate (SC) were explored. All dressings showed shear-thinning behavior with yield stress. Raising PSC increased storage (G') and loss (G") moduli decreasing loss tangent (tanδ) and samples containing ≥ 3 wt% starch showed a weak gel-like (tanδpotato starch may be suitable ingredient in low-fat dressings applications.

  10. Quantification of high-power ultrasound induced damage on potato starch granules using light microscopy.

    Zuo, Yue Yue J; Hébraud, Pascal; Hemar, Yacine; Ashokkumar, Muthupandian


    A simple light microscopic technique was developed in order to quantify the damage inflicted by high-power low-frequency ultrasound (0-160 W, 20 kHz) treatment on potato starch granules in aqueous dispersions. The surface properties of the starch granules were modified using ethanol and SDS washing methods, which are known to displace proteins and lipids from the surface of the starch granules. The study showed that in the case of normal and ethanol-washed potato starch dispersions, two linear regions were observed. The number of defects first increased linearly with an increase in ultrasound power up to a threshold level. This was then followed by another linear dependence of the number of defects on the ultrasound power. The power threshold where the change-over occurred was higher for the ethanol-washed potato dispersions compared to non-washed potato dispersions. In the case of SDS-washed potato starch, although the increase in defects was linear with the ultrasound power, the power threshold for a second linear region was not observed. These results are discussed in terms of the different possible mechanisms of cavitation induced-damage (hydrodynamic shear stresses and micro-jetting) and by taking into account the hydrophobicity of the starch granule surface.

  11. Effects of salts on physicochemical, microstructural and thermal properties of potato starch.

    Zhou, Hongxian; Wang, Chenjie; Shi, Liu; Chang, Tong; Yang, Hong; Cui, Min


    The objective of this study was to determine the effects of salts on the physicochemical, microstructural and thermal properties of potato starch. The salting-out ions were able to decrease the solubility, swelling power, transparency and particle size of potato starch significantly (ppotato starch granules, observed by a light microscopy at 50°C and 70°C, was consistent with the above results. Differential scanning calorimetry (DSC) analysis demonstrated an increase in gelatinization temperature and enthalpy with the addition of salting-out ions, whereas there was a reverse trend for the addition of salting-in ions. The effects of anions on these properties of potato starch follow the order of SCN(-)>I(-)>NO3(-)>Br(-)>Cl(-)>SO4(2-)>F(-), while effects of the cations follow the order of Li(+)>Na(+)>K(+), matching to the order of the Hofmeister series.

  12. Effect of Acetylation on the Properties of Sweet Potato Starch%乙酰化对红薯淀粉性质的影响

    张磊; 熊柳; 孙庆杰


    The low-substituted acetylated sweet potato starches were prepared using sweet potato starch as raw material and acetic anhydride as the esterifying agent. Through the preparation of different degrees of substitution of acetylated sweet potato starches(DS = 0.044 -0.096), compared with the sweet potato native starch, the properties of acetylation and native sweet potato starches were studies such as the transparency, retrogradation, solubility, swelling, viscosity and texture properties. The results showed that acetylation significantly decreased retrogradation of sweet potato starches. The transparency, swelling power and solubility of acetylated sweet potato starches all increased with the increase in acetyl substitution degree. The gelatinization temperature of acetylated sweet potato starch were reduced 6-10 t. The final viscosity and retrogradation value were significantly lower. The hardness in texture properties decreased significantly.%以红薯淀粉为原料,醋酸酐为乙酰化剂,制备低取代的乙酰化红薯淀粉.通过制备不同取代度乙酰化淀粉(DS 0.044~0.096),与红薯原淀粉进行比较,对乙酰化淀粉的透明度、凝沉性、溶解度、溶胀度、黏度和质构特性等进行深入研究.结果表明,与原淀粉相比,红薯淀粉经乙酰化作用后,凝沉性明显减弱,乙酰化红薯淀粉透明度、溶解度和溶胀度都随着取代度的增加而增加,且明显高于原淀粉.乙酰化红薯淀粉的糊化温度降低6~10℃,最终黏度和回生值显著降低,硬度显著降低.

  13. Preparation of Oxidized Potato Starch Adhesive%马铃薯氧化淀粉胶粘剂制备研究



    [ Objective ] The aim was to identify the oxidized potato starch adhesive preparation of the most appropriate oxidant. [ Method ] Potato starch was used as raw material, potassium permanganate, hydrogen peroxide, sodium hypochlorite as oxidant, the first oxidation of potato starch was conducted, and oxidized potato starch adhesive was prepared. Preparation of different oxidants and oxidation of potato starch carbonyl content,carboxyl content determination, oxidation of potato starch adhesive viscosity, water loss rate, initial viscosity, mobility, storage and other properties of the test were determined. [ Result] Under the same conditions, prepared by hydrogen peroxide in various adhesive properties of potato starch weve significantly better than the other oxidants preparation of the adhesive. [ Conclusion] Preparation of potato starch oxidation of hydrogen peroxide was the most suitable oxidant adhesive.%[目的]研究制备马铃薯氧化淀粉胶粘剂最合适的氧化剂.[方法]选用马铃薯淀粉为原料,以高锰酸钾、双氧水、次氯酸钠为氧化剂,先对马铃薯淀粉进行氧化,然后制备马铃薯氧化淀粉胶粘剂.对不同氧化剂制备的马铃薯氧化淀粉的羰基含量、羧基含量进行测定,并对马铃薯氧化淀粉胶粘剂的粘度、失水率、初粘性、流动性、贮存期等性能进行测试.[结果]在相同条件下,用双氧水制备的马铃薯淀粉胶粘剂的各个性能都明显优于其他氧化剂制备的胶粘荆.[结论]双氧水是制备马铃薯氧化淀粉胶粘剂最合适的氧化剂.

  14. The influence of gamma irradiation on texture, color and viscosity properties of potato starch

    Teixeira, Bruna S.; Inamura, Patricia Y.; Mastro, Nelida L. del, E-mail: [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)


    Food choices, while influenced by taste and nutritional value, have also symbolic enjoyment meanings. The texture, appearance, and flavor are important acceptability factors for any meal component. In our every day enjoyment of eating, texture is often as important as flavor. Starch is the most important source of carbohydrate in human nutrition and is widely used in many applications throughout the food industry. As an additive for food processing, food starches are typically used as thickeners and stabilizers in foods such as puddings, custards, soups, sauces, gravies, pie fillings, and salad dressings, and to make noodles and pastas. Potato starch is extracted from the root tubers of the potato plant. Radiation processing can be applied on foods for different purposes. It can also produce some modifications that are important to know. The aim of this research was to analyze the influence of gamma irradiation on texture, color and viscosity of potato starch. Starch samples were irradiated in a {sup 60}Co source Gammacell 220 with doses of 0, 5, 10 and 15 kGy. The results obtained showed that texture became inversely proportional to the applied radiation dose. Increasing doses promoted a slight rise in the parameter b* (yellow color) while the parameter L was not significantly affected. On the other hand, the viscosity of potato starch aqueous preparations decreased with the radiation dose, attributable to some degradation of starch molecules. (author)

  15. Intelligent pH indicator film composed of agar/potato starch and anthocyanin extracts from purple sweet potato.

    Choi, Inyoung; Lee, Jun Young; Lacroix, Monique; Han, Jaejoon


    A new colorimetric pH indicator film was developed using agar, potato starch, and natural dyes extracted from purple sweet potato, Ipomoea batatas. Both agar and potato starch are solid matrices used to immobilize natural dyes, anthocyanins. The ultraviolet-visible (UV-vis) spectrum of anthocyanin extract solutions and agar/potato starch films with anthocyanins showed color variations to different pH values (pH 2.0-10.0). Fourier transform infrared (FT-IR) and UV-vis region spectra showed compatibility between agar, starch, and anthocyanin extracts. Color variations of pH indicator films were measured by a colorimeter after immersion in different pH buffers. An application test was conducted for potential use as a meat spoilage sensor. The pH indicator films showed pH changes and spoilage point of pork samples, changing from red to green. Therefore, the developed pH indicator films could be used as a diagnostic tool for the detection of food spoilage.

  16. Study on the Gel-freezing Method Preparation Chinese Sweet Potato Microporous Starch%凝胶-冷冻法制备红薯微孔淀粉工艺的研究

    傅新征; 许海基; 张仪秀


    以红薯淀粉为原材料制备红薯微孔淀粉,以红薯微孔淀粉的吸水率和吸油率为指标,探讨并优化凝胶–冷冻法制备红薯微孔淀粉的工艺参数。结果表明,制备红薯微孔淀粉的优化工艺参数为:红薯淀粉乳浓度100 g/L、糊化时间40 min、冷冻时间39 h、糊化温度90℃,此工艺下制备的红薯微孔淀粉吸水率为467.51%、吸油率为76.36%。%Chinese sweet potato starch was used as the raw materials to prepared Chinese sweet potato microporous starch. The water absorption rate and oil absorption rate of Chinese sweet potato microporous starch were used as indexes, discuss and optimize the process conditions of the gel-freezing method preparation Chinese sweet potato microporous starch. The results showed that the optimum prepara-tion process conditions of Chinese sweet potato microporous starch:Chinese sweet potato starch milk concentration 10g/100ml, gelatiniza-tion time 40min, freezing time 39h, gelatinization temperature 90℃. Under the condition, the water absorption rate of Chinese sweet potato microporous starch was 467.51%, and the oil absorption rate of Chinese sweet potato microporous starch was 76.36%.

  17. The enzymatic determination of starch in food, feed and raw materials of the starch industry

    Brunt, K.; Sanders, P.; Rozema, T.


    An enzymatic starch determination which can be used for the analysis of starch in a very broad range of different samples is evaluated, ranging from starch in plants, feed and food to industrial applications as starch in starch. The method is based on a complete enzymatic conversion of the starch

  18. Quality evaluation of stiff porridges prepared from Irish potato (Solanum tuberosum) and pigeon pea (Cajanus cajan) starch blends.

    Abu, Joseph Oneh; Enyinnaya, Chinma Chiemela; James, Samaila; Okeleke, Ezinne


    Quality attributes of stiff porridges prepared from Irish potato and pigeon pea starch blends were studied. Starches were extracted from Irish potato and pigeon pea using a wet extraction method. Various ratios of the starches were mixed and analyzed for chemical, functional and pasting properties. The starch blends were then prepared into stiff porridges for sensory evaluation using a 20-man sensory panel. Substitution of Irish potato starch with pigeon pea starch led to increases in protein (0.15 to 1.2%), fat (0.26 to 0.56%) and ash (0.30 to 0.69%) while the amylose content of the starch blends decreased (from 23.8 to 18.4%) respectively. Functional properties such as bulk density (0.75 to 0.60 g/cm(3)), water absorption capacity (3.1 to 2.6 g water/ g sample) and dispersibility (58.6 to 42.7%) decreased significantly (P stiff porridges were not adversely affected by pigeon pea starch inclusion. Therefore it should be possible to incorporate up to 50% of low digestible pigeon pea starch into Irish potato starch from legumes such as pigeon pea as alternatives to cassava starch in the preparation of stiff porridges. Such porridges made from Irish potato and legume starches could provide additional incentive for individuals requiring decreased and or slow starch digestibility such as diabetics.

  19. Effect of Hydroxypropylation on Functional Properties of Different Cultivars of Sweet Potato Starch in Sri Lanka.

    Senanayake, Suraji; Gunaratne, Anil; Ranaweera, K K D S; Bamunuarachchi, Arthur


    Starches obtained from different cultivars of sweet potatoes commonly consumed in Sri Lanka, were chemically modified with hydroxypropyl substitution, to analyze the changes in the physicochemical properties. Significant changes (P syneresis) of starch gels (7.0% db) during cold and frozen storage were observed due to the modification. Hydroxypropylation increased the gel stability, water solubility, digestibility, and storage stability of the native starches in the cold storage to a significant level. Lowered gelatinization and retrogradation enthalpies as well as gelatinization temperature were observed for derivatized starches compared to the native starch. Low levels of pasting stability with increased levels of breakdown and reduced cold paste viscosity were observed in the hydroxypropylated starch samples except for the Malaysian cultivar (S5). Chemically modified starch gels stored under cold storage did not show a syneresis for two weeks in the cycle and the frozen storage showed much improved stability in the starch gels within the four-week cycle. Chemical modification of sweet potato starch with hydroxyl propyl substitution can enhance the functional characteristics of the native starch which will improve its potential application in the food industry.

  20. Effect of Hydroxypropylation on Functional Properties of Different Cultivars of Sweet Potato Starch in Sri Lanka

    Suraji Senanayake


    Full Text Available Starches obtained from different cultivars of sweet potatoes commonly consumed in Sri Lanka, were chemically modified with hydroxypropyl substitution, to analyze the changes in the physicochemical properties. Significant changes (P<0.05 in the crude digestibility level, thermal properties, and the water separation (syneresis of starch gels (7.0% db during cold and frozen storage were observed due to the modification. Hydroxypropylation increased the gel stability, water solubility, digestibility, and storage stability of the native starches in the cold storage to a significant level. Lowered gelatinization and retrogradation enthalpies as well as gelatinization temperature were observed for derivatized starches compared to the native starch. Low levels of pasting stability with increased levels of breakdown and reduced cold paste viscosity were observed in the hydroxypropylated starch samples except for the Malaysian cultivar (S5. Chemically modified starch gels stored under cold storage did not show a syneresis for two weeks in the cycle and the frozen storage showed much improved stability in the starch gels within the four-week cycle. Chemical modification of sweet potato starch with hydroxyl propyl substitution can enhance the functional characteristics of the native starch which will improve its potential application in the food industry.

  1. Effect of Microwave Heating on Potato and Tapioca Starches in Water Suspension

    Nurul Nadiah Ismail


    Full Text Available Abstract— The effects of microwave heating on properties of starch were studied on potato and tapioca starches in water suspension at different temperature (50°C and 60°C. Potato and tapioca starches were adjusted to 30% (w/v and heat-moisture treated in a microwave oven and conventional heating.Conventional heating was carried out by direct heating the moisture heated sample at 50ºC and 60ºC while the microwave heating was carried out by microwave oven and the temperature was controlled approximately to 50ºC and 60ºC. The heated starch samples were analyzed for amylose content, pasting properties, swelling and solubility, thermal properties, light microscopy, scanning electron microscopy (SEM and X-ray diffraction. There were present several changes on physicochemical and functional properties of heated starch for both heating methods. However, microwave method gave higher affect on heating treatment rather than conventional heating. Microwave heating was evidenced in affecting pasting properties of potato and tapioca starches by increase the pasting temperature and the paste stability. Microwave heating also significantly increased the amylose content and swelling power but reduced the solubility and enthalpy of gelatinization (ΔH of those starches. There were changes in granule structure of starch observed by loss of birefringence and ruptures granule in SEM micrographs in both heating treatment. A change in the X-ray diffraction pattern from B-type to A-type was occurred in potato starch but tapioca starch shows no changes in X-ray pattern.  

  2. Effect of Microwave Heating on Potato and Tapioca Starches in Water Suspension

    Nurul Nadiah binti Ismail


    Full Text Available The effects of microwave heating on properties of starch were studied on potato and tapioca starches in water suspension at different temperature (50°C and 60°C. Potato and tapioca starches were adjusted to 30% (w/v and heat-moisture treated in a microwave oven and conventional heating.Conventional heating was carried out by direct heating the moisture heated sample at 50oC and 60oC while the microwave heating was carried out by microwave oven and the temperature was controlled approximately to 50oC and 60oC. The heated starch samples were analyzed for amylose content, pasting properties, swelling and solubility, thermal properties, light microscopy, scanning electron microscopy (SEM and X-ray diffraction. There were present several changes on physicochemical and functional properties of heated starch for both heating methods. However, microwave method gave higher affect on heating treatment rather than conventional heating. Microwave heating was evidenced in affecting pasting properties of potato and tapioca starches by increase the pasting temperature and the paste stability. Microwave heating also significantly increased the amylose content and swelling power but reduced the solubility and enthalpy of gelatinization (ΔH of those starches. There were changes in granule structure of starch observed by loss of birefringence and ruptures granule in SEM micrographs in both heating treatment. A change in the X-ray diffraction pattern from B-type to A-type was occurred in potato starch but tapioca starch shows no changes in X-ray pattern.

  3. The change of amyloplasts structure and composition of storage starch in potato minitubers during imitated microgravity

    Nedukha, O. M.; Kordyum, E. L.; Martyn, G. M.; Schnyukova, E. I.

    Potato was designated for food production in the controlled ecological life-support system CELSS because its tubers as it is known contain starch and significant protein content and are edible food after the long-term storage We used the cultivation of potato miniplants under influence of long-term horizontal clinorotation 2 rev min which imitated microgravity as a model for the technology of potato food production in the CELSS The aim of our work was to determine content and composition storage starch as well as amyloplast ultrastructure of storage parenchyma cells in potato minitubers formed under long-term to 6 weeks slow horizontal clinorotation 2 rpm Minitubers developed from axillary buds of potato miniplants growing in the aseptic stationary conditions and under clinorotation Methods of scanning and transmission electron microscopy were used for the study of surface and ultrastructure of amyloplasts the biochemical method by Hovenkamp-Hermelink et al 1988 - for study of starch composition Some differences were observed in amyloplast structure under clinorotation namely increased volume of starch grains in plastid decreased stroma volume changed structure of envelope membranes in comparison with the stationary control Besides an appearance of fraction of gigantic amyloplasts in central layers of parenchyma was observed under clinorotation after 4 weeks of growth The total starch content increased and reached to 219 5 - 4 1 mg g FW at 6 weeks of clinorotation it was 167 5 - 5 6 mg g FW in the control minitubers A ratio of

  4. Characterization and Prebiotic Effect of the Resistant Starch from Purple Sweet Potato

    Yafeng Zheng


    Full Text Available Purple sweet potato starch is a potential resource for resistant starch production. The effects of heat-moisture treatment (HMT and enzyme debranching combined heat-moisture treatment (EHMT on the morphological, crystallinity and thermal properties of PSP starches were investigated. The results indicated that, after HMT or EHMT treatments, native starch granules with smooth surface was destroyed to form a more compact, irregular and sheet-like structure. The crystalline pattern was transformed from C-type to B-type with decreasing relative crystallinity. Due to stronger crystallites formed in modified starches, the swelling power and solubility of HMT and EHMT starch were decreased, while the transition temperatures and gelatinization enthalpy were significantly increased. In addition, HMT and EHMT exhibited greater effects on the proliferation of bifidobacteria compared with either glucose or high amylose maize starch.

  5. Characterization and Prebiotic Effect of the Resistant Starch from Purple Sweet Potato.

    Zheng, Yafeng; Wang, Qi; Li, Baoyu; Lin, Liangmei; Tundis, Rosa; Loizzo, Monica R; Zheng, Baodong; Xiao, Jianbo


    Purple sweet potato starch is a potential resource for resistant starch production. The effects of heat-moisture treatment (HMT) and enzyme debranching combined heat-moisture treatment (EHMT) on the morphological, crystallinity and thermal properties of PSP starches were investigated. The results indicated that, after HMT or EHMT treatments, native starch granules with smooth surface was destroyed to form a more compact, irregular and sheet-like structure. The crystalline pattern was transformed from C-type to B-type with decreasing relative crystallinity. Due to stronger crystallites formed in modified starches, the swelling power and solubility of HMT and EHMT starch were decreased, while the transition temperatures and gelatinization enthalpy were significantly increased. In addition, HMT and EHMT exhibited greater effects on the proliferation of bifidobacteria compared with either glucose or high amylose maize starch.

  6. Potato starch oxidation induced by sodium hypochlorite and its effect on functional properties and digestibility.

    Zhou, Fengchao; Liu, Qian; Zhang, Hongwei; Chen, Qian; Kong, Baohua


    The effects of different concentrations of sodium hypochlorite (active chlorine content at 0.1, 0.2, 1.0, 2.0, 3.0, and 4.0 g/100 g) on the properties of potato starch (PS) were investigated by determining the morphological, physicochemical, crystallinity, pasting, gel texture and digestive properties. The starch granules of PS oxidized with high oxidant concentrations caused cracks and pores, and oxidation mainly acts on the amorphous regions of the starch granules. As the sodium hypochlorite concentration increases, the carbonyl content, carboxyl content, solubility, and pasting temperature of PS increased, as measured using a Rapid Visco Analyser (RVA). The swelling power, breakdown, setback, and peak and final viscosities decreased according to the RVA (Pstarch. The slowly digestible starch and resistant starch contents increased significantly, while the rapidly digestible starch content decreased after the oxidation modification (Pstarch and decreased starch digestibility.

  7. Microbial starch-binding domains are superior to granule-bound starch synthase I for anchoring luciferase to potato starch granules

    JI Qin; Jean-Paul VINCKEN; Luc C.J.M. SUURS; Richard G.F. VISSER


    Microbial starch-binding domains (SBD) and granule-hound starch synthase I (GBSSI) are proteins which are accumulated in potato starch granules. The efficiency of SBD and GBSSI for targeting active luciferase reporter proteins to granules during starch biosynthesis was compared. GBSSI or SBD sequences were fused to the N- or C-terminus of the luciferase (LUC) gene, via an artificial Pro-Thr encoding linker sequence. The genes were introduced into an amylose-free (am f) potato mutant. It appeared that SBD was superior to GBSSI as a targeting sequence, mainly because the luciferase retained higher activity in the SBD-containing fusion proteins than in the GBSSI-containing ones.

  8. Domain C of thermostable α-amylase of Geobacillus thermoleovorans mediates raw starch adsorption.

    Mehta, Deepika; Satyanarayana, T


    The gene (1,542 bp) encoding thermostable Ca(2+)-independent and raw starch hydrolyzing α-amylase of the extremely thermophilic bacterium Geobacillus thermoleovorans encodes for a protein of 50 kDa (Gt-amyII) with 488 amino acids. The enzyme is optimally active at pH 7.0 and 60 °C with a t 1/2 of 19.4 h at 60 and 4 h at 70 °C. Gt-amyII hydrolyses corn and tapioca raw starches efficiently and therefore finds application in starch saccharification at industrial sub-gelatinisation temperatures. The starch hydrolysis is facilitated following adsorption of the enzyme to starch at the C-terminal domain, as confirmed by the truncation analysis. The adsorption rate constant of Gt-amyII to raw corn starch is 37.6-fold greater than that for the C-terminus truncated enzyme (Gt-amyII-T). Langmuir-Hinshelwood kinetic analysis in terms of equilibrium parameter (K R) suggested that the adsorption of Gt-amyII to corn starch is more favourable than that of Gt-amyII-T. Thermodynamics of temperature inactivation indicated a decrease in thermostabilisation of Gt-amyII upon truncation of its C-terminus. The addition of raw corn starch increased t 1/2 of Gt-amyII, but it has no such effect on Gt-amyII-T. It can, therefore, be stated that Gt-amyII binds to raw corn starch via C-terminal region that contributes to its thermostability. Phylogenetic analysis confirmed that starch binding region of Gt-amyII is, in fact, the non-catalytic domain C, and not the typical SBD of CBM families. The role of domain C in raw starch binding throws light on the evolutionary path of the known SBDs.

  9. Starch characterization in seven raw, boiled and roasted chestnuts (Castanea sativa Mill.) cultivars from Portugal.

    Silva, A P; Oliveira, I; Silva, M E; Guedes, C M; Borges, O; Magalhães, B; Gonçalves, B


    Changes occurring in seven chestnut (Castanea sativa sp.) cultivars, caused by boiling and roasting, on starch content, cell and starch granules dimension were evaluated, and morphological changes were characterized by scanning electron microscopy. Three clear patterns of variation were detected after processing, namely: i) decrease of starch content with processing; ii) starch increase with the applied treatments; iii) increase of starch with boiling and decrease with roasting. Starch granules of raw chestnuts presented round, oval or elliptical form, external smooth surface and eccentric hilum, with rather ellipsoid-shaped growth rings. Processing resulted in modifications of the granules, with fusion of individual granules, and gelatinization taking place with the formation of elongated clusters. The present results indicate that boiling and roasting, besides changing the starch content of chestnut, causes important modifications in the starch granules, which can affect the sensory, rheological and chemical characteristics of chestnuts.

  10. Effect of cultivar, location and year on total starch, amylose, phosphorus content and starch grain size of high starch potato cultivars for food and industrial processing.

    Šimková, Dagmar; Lachman, Jaromír; Hamouz, Karel; Vokál, Bohumil


    In recent time the interest of industry increases particularly in processing and use of potato high amylopectin (AMP) starches. Therefore the plant breeders effort to obtain "waxy" potato cultivars with low amylose (AMS) content. In this four-year study sixteen potato cultivars grown on five experimental locations were evaluated on the percentage of AMS/AMP by enzymatic method, starch content by the underwater weight method, phosphorus (P) content in starch digests spectrophotometrically, and starch granule size determined by laser diffraction method. Between enzymatic and iodine-potassium iodide method good correlation has been revealed (r=0.71). The correlation analysis between AMS and P levels showed a clear negative correlation. For all measured parameters (starch, AMS, P, starch granule size) significant impact of cultivar has been determined. Location and year have lower, but significant impact. No statistically significant effect of year on AMS has been found. The cultivar Amado distinguished with the highest AMP and P contents and the cultivar Westamyl showed all positive values interesting for growers and processors.

  11. Effect of repeated retrogradation on structural characteristics and in vitro digestibility of waxy potato starch.

    Xie, Yao-Yu; Hu, Xiao-Pei; Jin, Zheng-Yu; Xu, Xue-Ming; Chen, Han-Qing


    The effects of repeated retrogradation (RR) treatment on the structural characteristics and in vitro digestibility of waxy potato starch were investigated. The cycling times of RR ranging from 1 to 5 were designated as RR-1, RR-2, RR-3, RR-4, and RR-5, respectively. A maximum SDS content (40.41%) was obtained by RR-2 treatment with the time interval of 48h. RR-2-treated starch product exhibited a narrower melting temperature range, a higher onset temperature and a lower melting enthalpy compared with RR-1 treatment. Compared with native starch, X-ray diffraction patterns of treated starches were altered from B-type to C-type. The variation in relative crystallinity of RR-treated starch products was consistent with that in melting enthalpy. Moreover, compared with RR-1-treated starch, a large number of cavities were observed on the surface of RR-2-treated starch product with a time interval of 48h, whereas more smooth regions were found on the surface of RR-5-treated starch product. This study suggested that structural changes of waxy potato starch treated with different cycling times of RR significantly affected the digestibility.

  12. Characterization and flocculation mechanism of a bioflocculant from potato starch wastewater.

    Guo, Junyuan; Lau, Anthony K; Zhang, Yuzhe; Zhao, Jing


    This study investigated the characterization and flocculation mechanism of a bioflocculant prepared using potato starch wastewater. The optimal culture conditions of this strain were determined as 4 g K2HPO4, 2 g KH2PO4, 0.2 g MgSO4, 0.1 g NaCl, and 2.0 g urea dissolved in 1.0 L potato starch wastewater with no need of adding carbon sources or adjusting pH value. Production of this bioflocculant was positively associated with cell growth, and a highest value of 0.81 g/L was obtained. During the kaolin suspension flocculation, charge neutralization and interparticle bridging were proposed as the main reasons for enhanced performance. Further, with potato starch wastewater, chemical oxygen demand (COD) and turbidity removal rates reached 52.4 and 81.7 %, respectively, at pH 7.5 when the bioflocculant dose was adjusted to 30 mg/L.

  13. Effects of phosphorus contents on the gelatinization and retrogradation of potato starch.

    Karim, A A; Toon, L C; Lee, V P L; Ong, W Y; Fazilah, A; Noda, T


    Effects of phosphorus content (510 to 987 ppm) on the gelatinization and retrogradation of 6 potato cultivars (Benimaru, Hokkaikogane, Irish Cobbler, Konafubuki, Sakurafubuki, and Touya) were studied. Pasting properties were analyzed by RVA, thermal properties by DSC, and mechanical properties of the starch gels by TA. Phosphorus was positively correlated with swelling power (r= 0.84) and negatively correlated with solubility (r= 0.83). Phosphorus content showed significant effect on certain pasting properties of potato starch such as peak viscosity, breakdown, and setback. Phosphorus content showed a significant positive correlation with peak viscosity (r= 0.95) and breakdown (r= 0.90). Increasing concentration of phosphorus tends to decrease the setback. Phosphorus content had no influence on thermal properties and mechanical properties of potato starch gel.

  14. Effects of selenium treatments on potato (Solanum tuberosum L.) growth and concentrations of soluble sugars and starch.

    Turakainen, Marja; Hartikainen, Helinä; Seppänen, Mervi M


    The effect of selenium (Se) treatments on potato growth and Se, soluble sugar, and starch accumulation was investigated. Potato plants were cultivated in quartz sand without or with sodium selenate (0, 0.075, 0.3 mg Se kg(-1) sand). In young potato plants, Se treatment resulted in higher starch concentrations in upper leaves. The tuber yield of Se-treated potato plants was higher and composed of relatively few but large tubers. At harvest, the starch concentration in tubers did not differ significantly between treatments. The higher Se addition (0.3 mg Se kg(-1)) may have delayed the aging of stolons and roots, which was observed as high concentrations of soluble sugar and starch. Together with the earlier results showing elevated starch concentration in Se-treated lettuce, the findings of this research justify the conclusion that Se has positive effects also on potato carbohydrate accumulation and possibly on yield formation.

  15. Feasibility study on fermentative conversion of raw and hydrolyzed starch to hydrogen using anaerobic mixed microflora

    Wang, Ching-Hsiung [Department of Biological Engineering, Yung Ta Institute of Technology and Commerce, Pingtung (China); Lu, Wei-Bin [Department of Cosmetic Science, Chung Hwa College of Medical Technology, Tainan (China); Chang, Jo-Shu [Department of Chemical Engineering, National Cheng Kung University, Tainan 701 (China)


    In this work, H{sub 2} was produced by anaerobic mixed microflora with phosphate-buffered medium containing starch or enzyme-treated starch hydrolyzate as the carbon substrate. The effect of pH on H{sub 2}-producing performance was examined for cultures converting raw starch or hydrolyzed starch into H{sub 2}. Response surface methodology was utilized to determine the best condition (41 C, pH 5.2, 2.1% (v/v) enzyme dosage, 27 h reaction time) for starch hydrolysis with concentrated crude amylase obtained from Bacillus subtilis ATCC 21332. The mixed culture was able to produce H{sub 2} at an optimal pH of 7.0 irrespective of raw or hydrolyzed starch. Direct starch fermentation attained a highest maximum H{sub 2} production rate (R{sub max}), overall H{sub 2} production rate (R{sub overall}), and H{sub 2} yield (Y{sub H2}) of 25.6 ml/h, 88 ml/h/l, and 5.28 mmol H{sub 2}/g starch (4.64 mmol H{sub 2}/g COD), respectively. In contrast, using hydrolyzed starch as the substrate gave rise to much better H{sub 2} producing performance, as the highest R{sub max}, R{sub overall}, and Y{sub H2} values increased to 43.1 ml/h, 210 ml/h/l, and 6.1 mmol H{sub 2}/g COD, respectively. This clearly demonstrates the advantage of using hydrolyzed starch for fermentative H{sub 2} production. The soluble metabolites consisted primarily of acetate (HAc), ethanol (EtOH), butyrate (HBu), and 2,3 butandiol. The amount of H{sub 2} produced from raw and hydrolyzed starch (especially, raw starch) could be estimated from formation of HAc and HBu known to stoichiometrically correlate with H{sub 2} production. (author)

  16. Synthesis and characterization of a novel potato starch derivative with cationic acetylcholine groups.

    Zhang, Bing; Ni, Boli; Lü, Shaoyu; Cui, Dapeng; Liu, Mingzhu; Gong, Honghong; Han, Fei


    A novel substance, cationic acetylcholine potato starch (CAPS), was developed for the first time. The synthesis process had three steps: first, carboxymethyl potato starch (CMPS) was synthesized under sodium hydroxide alkaline condition and in isopropyl alcohol organic media; second, bromocholine chloride (BCC) was synthesized with sulphuric acid as a catalytic agent; finally, CAPS was synthesized by the reaction of CMPS with BCC in N,N'-dimethylformamide (DMF). The degree of substitution (DS) of CAPS was determined by ammonia gas-sensing electrode and elemental analysis. CAPS was characterized by Fourier transformed infrared (FTIR) and near infrared (FTNIR) spectroscopy, scanning electron microscopy (SEM), X-ray diffraction (XRD) and differential scanning calorimetry (DSC).

  17. Statistically designed optimisation of enzyme catalysed starch removal from potato pulp

    Thomassen, Lise Vestergaard; Meyer, Anne S.


    Potato pulp is a high-volume, low-value byproduct stream resulting from the industrial manufacture of potato starch. The pulp is a rich source of biologically functional dietary fibers, but the targeted valorisation of the fibers requires removal of the residual starch from the pulp. The objective...... to obtain dietary fibers is usually accomplished via a three step, sequential enzymatic treatment procedure using a heat stable alpha-amylase, protease, and amyloglucosidase. Statistically designed experiments were performed to investigate the influence of enzyme dose, amount of dry matter, incubation time...

  18. Studies on sweet potatoes. Pt. 2. Isolation and characterization of starch

    Madhusudhan, B.; Susheelamma, N.S.; Tharanathan, R.N. (Central Food Technological Research Inst., Mysore (India). Dept. of Food Chemistry)


    By differntial sedimentation and centrifugation steps four starch isolates were recovered from sun dried sweet potato flour. The granules in these isolates were of different size, shape and population characteristics, and were anionic in nature. They showed a single stage swelling with 30 to 35% solubility in water and only [proportional to]30% solubility in DMSO even after 72 h. Their starch content varied from [proportional to]48 to 88%. The presence of thermostable amylases in sweet potato resulted in considerable decrease in Brabender viscosity values as amylographic studies in the presence of HgCl[sub 2] showed significant increase in peak (PV) and setback (SBV) viscosities. The starch isolate I had 25% higher PV as compared to the isolate II but retrogradation was much low in this. Susceptibility to glucoamylase digestion showed a decreasing trend from the isolate I to the IV on solid basis, but comparable on starch basis. (orig.).

  19. Changes in crystal structure and physicochemical properties of potato starch treated by induced electric field.

    Li, Dandan; Yang, Na; Jin, Yamei; Zhou, Yuyi; Xie, Zhengjun; Jin, Zhengyu; Xu, Xueming


    The effects of induced electric field (IEF) on the crystal structure and physicochemical properties of potato starch were investigated by subjecting identically treated control and electrically-modified samples to the same temperature history. Additionally, a method of combining IEF with heating for efficient modification of native polymer was also proposed. Results showed that the application of IEF at an electric voltage of 75V has a statistically significant effect on starch gelatinization and pasting properties, especially when combined with heating at 50°C. After treatment by the combination method for 96h, the gelatinization temperatures increased, which can be explained by the slight increase in the ratio of 1044/1015cm(-1) and relative crystallinity. Furthermore, IEF reduced granular swelling and therefore contributed to decreasing the peak, breakdown, and setback viscosity of potato starch. This study explores the potential of IEF as innovative technology for starch modification.

  20. Gelatin/potato starch edible biocomposite films: Correlation between morphology and physical properties.

    Podshivalov, Aleksandr; Zakharova, Mariia; Glazacheva, Ekaterina; Uspenskaya, Mayya


    The paper presents the results of studies of the microstructure morphology and the operational properties of the gelatin/potato starch/glycerol edible biocomposite films varying in the starch content from 0 to 50wt% prepared by casting film-forming solution and dying at 36°C for 15h. The biocomposite films were shown phase separated heterogeneous morphology with the gelatin matrix as a continuous phase and microgranules of starch as a minor phase. It is found that when the starch content ≤ 30wt% the phase separation mechanism is nucleation and grow, whereas the starch content > 30wt% then the spinodal decomposition is the dominant mechanism. The work focuses on findings the influence of the phase separation mechanisms on the size of starch granules during the drying process, as well as the impact of these mechanisms on optical, frictional, mechanical, thermal and water-barrier properties.

  1. Highly phosphorylated functionalized rice starch produced by transgenic rice expressing the potato GWD1 gene

    Chen, Yaling; Sun, Xiao; Zhou, Xin Mao


    . The gelatinization temperatures of both rice flour and extracted starch were significantly lower than those of the control and hence negatively correlated with the starch phosphate content. The 6-P content was positively correlated with amylose content and relatively long amylopectin chains with DP25-36, and the 3-P......Starch phosphorylation occurs naturally during starch metabolism in the plant and is catalysed by glucan water dikinases (GWD1) and phosphoglucan water dikinase/glucan water dikinase 3 (PWD/GWD3). We generated six stable individual transgenic lines by over-expressing the potato GWD1 in rice....... Transgenic rice grain starch had 9-fold higher 6-phospho (6-P) monoesters and double amounts of 3-phospho (3-P) monoesters, respectively, compared to control grain. The shape and topography of the transgenic starch granules were moderately altered including surface pores and less well defined edges...

  2. Evaluation of nutritional profiles of starch and dry matter from early potato varieties and its estimated glycemic impact.

    Pinhero, Reena Grittle; Waduge, Renuka Nilmini; Liu, Qiang; Sullivan, J Alan; Tsao, Rong; Bizimungu, Benoit; Yada, Rickey Y


    To identify healthier potatoes with respect to starch profiles, fourteen early varieties were evaluated for their dietary fiber, total starch, rapidly digestible (RDS), slowly digestible (SDS), and resistant (RS) starch for nutrition and with regard to estimated glycemic index (eGI) and glycemic load (eGL). While all these profiles were highly dependent on the potato variety, eleven out of fourteen varieties were classified as low GL foods (pstarch factors contributing to eGI.

  3. Quality evaluation of yoghurt stabilized with sweet potato (Ipomoea batatas) and taro (Colocassia esculenta) starch

    Aysha Sameen; Muhammad Issa Khan; Muhammad Umair Sattar; Asma Javid; Aimen Ayub


    Stabilizers are important component in manufactured products such as yoghurt. The addition of stabilizers improves body, texture, appearance, mouth feel and prevents technical defects such as synersis in yoghurts. In this study starch was extracted from plant sources (sweet potato, taro) with and without use of chemicals. Yoghurt was enriched with different levels of extracted starch. Yoghurt samples were analyzed for physicochemical and functional attributes such as pH, acidity, synersis, wa...

  4. Engineering potato starch with a higher phosphate content

    Xu, Xuan; Huang, Xing Feng; Visser, Richard G.F.; Trindade, Luisa M.


    Phosphate esters are responsible for valuable and unique functionalities of starch for industrial applications. Also in the cell phosphate esters play a role in starch metabolism, which so far has not been well characterized in storage starch. Laforin, a human enzyme composed of a carbohydrate-bindi

  5. Application of Hydrothermally Modified Sweet Potato Starch as a Substitute Additive for Soup Mixture

    S. A. Senanayake


    Full Text Available Potential application of modified sweet potato starch as a substitute thickener for corn starch was studied, by using native starches extracted from five different cultivars of sweet potatoes commonly available in Sri Lanka. Physicochemical properties (swelling power, water solubility index, pasting, and gelatinization and digestibility of native and modified (heat-moisture treated, 20% moisture, 85°C for 6 hrs starches were analysed. Modified Swp3 (Wariyapola white, Swp4 (Pallepola, and Swp5 (Malaysian starches were selected based on the favourable conditions shown in the required physical and chemical properties and applied in a vegetable soup formula as a thickening aid. Corn starch added samples were kept as controls and the viscosity difference and sensory attributes were tested. Viscosity of the reconstituted soup powder and sensory analysis showed that Swp4 and Swp5 had significantly high level (P<0.05 of sensory quality and the average rank for mouth feel (taste, texture and overall acceptability was significantly high (P<0.05 in Swp5 added samples. Shelf life studies ensured 6 months of stability with negligible level of moisture increase and total plate count in air tight polypropylene packages at ambient temperatures (28–31°C. Results of this study revealed a possibility of applying physically modified Swp4 and Swp5 starches as a substituent food ingredient for commercially available corn starch to improve the thickness of food products.

  6. Effect of resistant starch on net portal-drained viscera flux of glucose, volatile fatty acids, urea, and ammonia in growing pigs

    Meulen, van der J.; Bakker, G.C.M.; Bakker, J.G.M.; Visser, de H.; Jongbloed, A.W.; Everts, H.


    Net portal-drained viscera (PDV) flux of glucose, VFA, ammonia, and urea was determined in pigs fed diets with or without resistant starch. Diets consisted of 65% cornstarch (diet CS), 32.5% cornstarch and 32.5% raw potato starch (diet CPS), or 65% raw potato starch (diet PS); the remaining 35% supp

  7. Distribution of phosphorus and hydroxypropyl groups within granules of modified sweet potato starches as determined after chemical peeling

    Zhao, J.; Schols, H.A.; Chen Zenghong,; Jin, Z.; Buwalda, P.; Gruppen, H.


    The distributions of phosphorus and hydroxypropyl groups within granules of cross-linked and hydroxypropylated sweet potato starches were investigated. Chemical surface peeling of starch granules was performed after sieving of native and modified starches into large-size (diameter = 20 µm) and small

  8. Engineering Saccharomyces cerevisiae for direct conversion of raw, uncooked or granular starch to ethanol.

    Görgens, Johann F; Bressler, David C; van Rensburg, Eugéne


    The production of raw starch-degrading amylases by recombinant Saccharomyces cerevisiae provides opportunities for the direct hydrolysis and fermentation of raw starch to ethanol without cooking or exogenous enzyme addition. Such a consolidated bioprocess (CBP) for raw starch fermentation will substantially reduce costs associated with energy usage and commercial granular starch hydrolyzing (GSH) enzymes. The core purpose of this review is to provide comprehensive insight into the physiological impact of recombinant amylase production on the ethanol-producing yeast. Key production parameters, based on outcomes from modifications to the yeast genome and levels of amylase production, were compared to key benchmark data. In turn, these outcomes are of significance from a process point of view to highlight shortcomings in the current state of the art of raw starch fermentation yeast compared to a set of industrial standards. Therefore, this study provides an integrated critical assessment of physiology, genetics and process aspects of recombinant raw starch fermenting yeast in relation to presently used technology. Various approaches to strain development were compared on a common basis of quantitative performance measures, including the extent of hydrolysis, fermentation-hydrolysis yield and productivity. Key findings showed that levels of α-amylase required for raw starch hydrolysis far exceeded enzyme levels for soluble starch hydrolysis, pointing to a pre-requisite for excess α-amylase compared to glucoamylase for efficient raw starch hydrolysis. However, the physiological limitations of amylase production by yeast, requiring high biomass concentrations and long cultivation periods for sufficient enzyme accumulation under anaerobic conditions, remained a substantial challenge. Accordingly, the fermentation performance of the recombinant S. cerevisiae strains reviewed in this study could not match the performance of conventional starch fermentation processes

  9. Gelatinization and freeze-concentration effects on recrystallization in corn and potato starch gels.

    Ronda, Felicidad; Roos, Yrjö H


    Freeze-concentration of starch gels was controlled by temperature and gelatinization with glucose and lactose. The aim of the study was to evaluate the effects of freezing temperature and gel composition on starch recrystallization behaviour of corn and potato starch gels (water content 70%, w/w) in water or glucose or lactose (10%, w/w) solutions. Starch gels were obtained by heating in differential scanning calorimetry (DSC). Samples of starch gels were frozen at -10 degrees C, -20 degrees C and -30 degrees C for 24h and, after thawing, stored at +2 degrees C for 0, 1, 2, 4 and 8 days. The extent of starch recrystallization was taken from the enthalpy of melting of the recrystallized starch by DSC. Freezing temperatures, glucose, lactose and the origin of the starch affected the recrystallization behaviour greatly. The recrystallization of amorphous starch during storage was enhanced by freeze-concentration of gels at temperatures above T'(m). Molecular mobility was enhanced by unfrozen water and consequently molecular rearrangements for nucleation could take place. Further storage at a higher temperature enhanced the growth and the maturation of crystals. In particular, glucose decreased the T'(m) of the gels and consequently lower freezing temperatures were needed to reduce enhanced recrystallization during storage. Freeze-concentration temperatures also showed a significant effect on the size and the perfection of crystals formed in starch recrystallization.

  10. Molecular cloning and 3D structure prediction of the first raw-starch-degrading glucoamylase without a separate starch-binding domain.

    Hostinová, Eva; Solovicová, Adriana; Dvorský, Radovan; Gasperík, Juraj


    Raw-starch-degrading glucoamylases have been known as multidomain enzymes consisting of a catalytic domain connected to a starch-binding domain (SBD) by an O-glycosylated linker region. A molecular genetics approach has been chosen to find structural differences between two related glucoamylases, raw-starch-degrading Glm and nondegrading Glu, from the yeasts Saccharomycopsis fibuligera IFO 0111 and HUT 7212, respectively. We have found that Glm and Glu show a high primary (77%) and tertiary structure similarity. Glm, although possessing a good ability for raw starch degradation, did not show consensus amino acid residues to any SBD found in glucoamylases or other amylolytic enzymes. Raw starch binding and digestion by Glm must thus depend on the existence of a site(s) lying within the intact protein which lacks a separate SBD. The enzyme represents a structurally new type of raw-starch-degrading glucoamylase.

  11. Effects of Ingredients and Extrusion Parameters on Aquafeeds Containing DDGS and Potato Starch

    Isocaloric (3.05 kcal/g) ingredient blends were factorially formulated using three levels each of DDGS (20, 25, and 30% db), protein (30, 32.5, and 35% db), and feed moisture content (25, 35, and 45% db), along with appropriate quantities of potato starch, soybean meal, fish meal, whey, vitamin, and...

  12. Gas-solid hydroxyethylation of potato starch in a stirred vibrating fluidized bed reactor

    Kuipers, N.J M; Stamhuis, Eize; Beenackers, A.A C M


    A novel reactor for modifying cohesive C-powders such as in the gas-solid hydroxyethylation of semidry potato starch is characterized, the so-called stirred vibrating fluidized bed reactor. Good fluidization characteristics are obtained in this reactor for certain combinations of stirring and vibrat

  13. Preparation and properties of cold-water-soluble sweet potato starch%冷水可溶甘薯淀粉的制备及性能

    陆珠华; 冉龙强; 陆国权


    以甘薯淀粉为原料,采用乙醇-碱法对冷水可溶甘薯淀粉(CWS)的制备进行了研究,优化了制备冷水可溶甘薯淀粉的工艺条件,并对冷水可溶甘薯淀粉的黏度特性、凝沉性和透明度进行了测定.结果表明,冷水可溶甘薯淀粉的最佳制备工艺条件为:乙醇体积分数80%,料液比为1∶5(g/mL),氢氧化钠溶液(3mol/L)加入量为30mL,反应温度35℃.在最佳条件下,冷水可溶甘薯淀粉的溶解度可高达87.92%.扫描电镜观察表明,冷水可溶甘薯淀粉颗粒表面有较大的凹陷和一些孔洞并且发生黏连,使其具有较好溶解性和粘性,并且其糊的凝沉性、抗剪切稳定性加强,但透明度有所降低.%The preparation of cold-water-soluble sweet potato starch was studied using alcohol-alkaline method,sweet potato starch as raw materials.The process conditions for preparing cold-water-soluble sweet potato starch were optimized.At same time,the viscosity property,retrogradation,and transparency of cold-watersoluble sweet were also determined.The results indicated that the best process conditions for preparing coldwater-soluble sweet potato starch were:amount of sodium hydroxide 30mL,volume concentration of ethanol 80%,alkalization temperature 35℃,and ratio of solid to liquid 1∶5.Under the best conditions,the solubility of CWS sweet potato starch would reach 87.92%.The scanning electronic microscope revealed a lot of depressions and keyholes on the surface of CWS sweet potato starch particles,including the existence of adhesion of both,which made its great solubility and viscosity.What's more,retrogradation,stability of the starch paste were all better than the original one.However,the transparency had been reduced.

  14. Preparation and evaluation of sweet potato starch-blended sodium alginate microbeads

    Jha Antesh


    Full Text Available The design of effective drug delivery systems has recently become an integral part of the development of new medicines. Hence, research continuously keeps searching for ways to deliver drugs over an extended period of time with a well- controlled release profile. The ionotropic gelation method was used to prepare sweet potato starch-blended controlled release alginate microbeads of ibuprofen. Sweet potato is an important crop in many developing countries. Although sweet potato originated from Central America, its ability to adapt to a wide variety of climatic conditions allows it to grow both in tropical and in moderate temperature regions of Africa, Asia and the Americas. The influence of various formulation factors such as in vitro drug release, entrapment efficiency, swelling study and micrometric properties was investigated. Other variables included sweet potato starch concentration, percentage drug loading, curing time, cross-linking agent and stirring speed during the microencapsulation process. The entrapment efficiencies were found in the range of 71.85 ± 2.04 - 94.53 ± 1.02%. The particle sizes were found in the range of 0.82 ± 0.006 - 1.08 ± 0.009 mm. This suggested that the ionotropic gelation method was successful in producing sweet potato starch-blended alginate microbeads.

  15. Towards industrially feasible treatment of potato starch processing waste by mixed cultures.

    Liu, Bingnan; Song, Jinzhu; Li, Ying; Niu, Jia; Wang, Zhenyu; Yang, Qian


    The present study aimed at reducing the pollution of the waste generated by the potato starch industry to the environment and transform the potato pulp and wastewater into single-cell protein (SCP) to be used as animal feed. The chemical oxygen demand of the wastewater was reduced from 26,700 to 9,100 mg/L by batch fermentation with mixed cultures in an aerated 10-L fermenter. The SCP products, with a crude protein content of 46.09 % (higher than soybean meal), were found palatable and safe for mice. During the treatment process, the microbial community was analyzed using the terminal restriction fragment length polymorphism for bacterial 16S rRNA genes. The results of the analysis suggested that Curacaobacter/Pseudoalteromonas and Paenibacillus/Bacillus were the main microorganisms in treating potato starch processing wastes. The 150-m(3)-scale fermentation demonstrated a potential for treatment in industrial applications. Fermentation of potato pulp and wastewater without adding an extra nitrogen source was a novel approach in treating the potato starch processing waste.

  16. A photographic approach to the possible mechanism of retrogradation of sweet potato starch.

    Lian, Xijun; Zhao, Shuyi; Liu, Qinsheng; Zhang, Xu


    Although the subject of starch retrogradation has been studied for about 20 years, the mechanism of starch retrogradation seems not yet to be completely established. In this paper, the possible retrogradation mechanism of sweet potato starch was postulated from four optical micrographs at the stages of melting of the starch granules, autoclaving treatment and aging. The possible process of retrogradation consists of three stages. Firstly, starch granules was swelled and melted with loss of X-ray crystallinity and formation of both crystalline and amorphous lamellae; secondly, in crystalline lamellae, amylopectin began to form nucleation when they were autoclaved; finally, the nucleus grew up to great rod-like crystals as the result of congregating of amylose on plates which were composed of and prolongated by amylopectin.

  17. Esterification of potato starch by a biocatalysed reaction in an ionic liquid.

    Zarski, Arkadiusz; Ptak, Sylwia; Siemion, Przemyslaw; Kapusniak, Janusz


    In this study, potato starch was esterified with oleic acid, using 1-butyl-3-methylimidazolium chloride as a reaction medium and an immobilised lipase from Thermomyces lanuginosus as a catalyst. The degree of substitution (DS) of the products was determined by the volumetric method; and the best esterified product (with the highest DS) was determined by an elemental analysis. The effect of the reaction parameters on the DS, such as the time and the temperature, were also studied. The product with the highest DS (0.22) was found in the reaction carried out at 60 °C for 4h. Fourier transform infrared (FTIR) and nuclear magnetic resonance (NMR) analyses confirmed the esterification of the potato starch. Furthermore, the results of X-ray diffraction (XRD) and a scanning electron microscopy (SEM) revealed that the crystallinity and the morphology of the native potato starch was slightly changed during its partial gelatinisation in the ionic liquid, and was completely destroyed as a result of the formation of the esters. The thermal stability of the starch oleate decreased, when compared to the unmodified starch, as was indicated by a thermal gravimetric analysis (TGA).

  18. Quality evaluation of yoghurt stabilized with sweet potato (Ipomoea batatas and taro (Colocassia esculenta starch

    Aysha Sameen


    Full Text Available Stabilizers are important component in manufactured products such as yoghurt. The addition of stabilizers improves body, texture, appearance, mouth feel and prevents technical defects such as synersis in yoghurts. In this study starch was extracted from plant sources (sweet potato, taro with and without use of chemicals. Yoghurt was enriched with different levels of extracted starch. Yoghurt samples were analyzed for physicochemical and functional attributes such as pH, acidity, synersis, water holding capacity, viscosity, total solids and sensory profile. Use of chemically extracted starches at the level of 0.3-0.4% (Sweet potato and 0.2-0.3% (Taro   in yoghurt manufacturing showed better  results  in  terms  of  lowering synersis, increasing water holding capacity, viscosity and overall acceptability as compared to the yoghurt containing stabilizer i.e. gelatin 0.5% w/w. Use of starches did not significantly affect the sensory attributes. Yoghurt that contains sweet potato and taro starch at 0.5% gave excellent results for water holding capacity, viscosity and for all sensory attributes as compared to gelatin

  19. Physicochemical properties of starches and expression and activity of starch biosynthesis-related genes in sweet potatoes.

    Lai, Yung C; Wang, Shu Y; Gao, Huan Y; Nguyen, Khiem M; Nguyen, Chinh H; Shih, Ming C; Lin, Kuan H


    The functional properties of starches from six sweet potato varieties containing various starch components and structures were studied in an attempt to identify starch sources for industrial uses. Tainan 18 (TNN18) with high-amylose (AM) starch exhibited high setback and breakdown viscosities, high water solubility at 85°C but low swelling volume at 65°C, and high hardness and adhesiveness; in contrast, the low-AM starch of Tainung 31 (TNG31) had opposite characteristics. Seven genes related to starch biosynthesis were tested, and GBSS, SS, SBEII, ISA, and AGPase were highly expressed in TNN18 and TNG31; however, transcript levels in DBE and SBE were extremely low. GBSS and SS activity reflected the abundance of GBSS and SS mRNA in TNG31 and TNN18, and expression of AGPase, GBSS, SS, and SBE in TNN18 substantially increased content of AM. The expression and activity of DBE had a significant effect on TNG31 with increased AP content.

  20. Influence of gamma radiation on potato starch gelatinization studied by differential scanning calorimetry

    Cieśla, Krystyna; Eliasson, Ann-Charlotte


    The paper presents a study of the influence of the conditions applied during differential scanning calorimetry (DSC) measurements (concentration and heating rate) on the possible detection of the differences between gelatinization occurring in both non-irradiated and irradiated potato starch with a dose of 20 kGy. Differences in gelatinization of irradiated and non-irradiated potato starch during DSC analysis was attributed to the radiation induced destruction of crystalline ordering. This was confirmed by studies of the samples irradiated to very high doses (446 and 600 kGy), and by comparing with the effect of grinding. Changes of starch properties caused by radiodepolymerization—contrary to those caused by grinding—influences gelatinization behaviour much more than the WAXS crystallinity in solid state.

  1. Influence of gamma radiation on potato starch gelatinization studied by differential scanning calorimetry

    Ciesla, Krystyna E-mail:; Eliasson, A.-C


    The paper presents a study of the influence of the conditions applied during differential scanning calorimetry (DSC) measurements (concentration and heating rate) on the possible detection of the differences between gelatinization occurring in both non-irradiated and irradiated potato starch with a dose of 20 kGy. Differences in gelatinization of irradiated and non-irradiated potato starch during DSC analysis was attributed to the radiation induced destruction of crystalline ordering. This was confirmed by studies of the samples irradiated to very high doses (446 and 600 kGy), and by comparing with the effect of grinding. Changes of starch properties caused by radiodepolymerization--contrary to those caused by grinding--influences gelatinization behaviour much more than the WAXS crystallinity in solid state.

  2. Expression of Thermobifida fusca thermostable raw starch digesting alpha-amylase in Pichia pastoris and its application in raw sago starch hydrolysis.

    Yang, Chao-Hsun; Huang, Yu-Chun; Chen, Cheng-Yu; Wen, Chia-Ying


    A gene encoding the thermostable raw starch digesting alpha-amylase in Thermobifida fusca NTU22 was amplified by PCR, sequenced and cloned into Pichia pastoris X-33 host strain using the vector pGAPZalphaA, allowing constitutive expression and secretion of the protein. Recombinant expression resulted in high levels of extracellular amylase production, as high as 510 U/l in the Hinton flask culture broth. The purified amylase showed a single band at about 65 kDa by SDS-polyacrylamide gel electrophoresis after being treated with endo-beta-N-acetylglycosaminidase H, and this agrees with the predicted size based on the nucleotide sequence. About 75% of the original activity remained after heat treatment at 60 degrees C for 3 h. The optimal pH and temperature of the purified amylase were 7.0 and 60 degrees C, respectively. The purified amylase exhibited a high level of activity with raw sago starch. After 48-h treatment, the DPw of raw sago starch obviously decreased from 830,945 to 378,732. The surface of starch granules was rough, and some granules displayed deep cavities.

  3. Pasting, textural and thermal properties of resistant starch prepared from potato (Solanum tuberosum) starch using pullulanase enzyme.

    Reddy, Chagam Koteswara; Pramila, S; Haripriya, Sundaramoorthy


    Pullulanase enzyme (40 U/g, 10 h) was used for enzymatic hydrolysis of potato starch which was autoclaved (121 °C/30 min), stored under refrigeration (4 °C/24 h) and lyophilized. Comparison of morphological, pasting, textural and thermal properties among native hydrolysed starch (V2) and gelatinized hydrolysed starch (V3) prepared using pullulanase enzyme on potato starch (V1) were studied. The round, elliptical, irregular and oval shape with smooth surface of V1 was replaced with amorphous mass of cohesive structure leading to loss of granular appearance in V2 and V3. The percentage of amylose and resistant starch content of V2 (27.16 %) and (24.16 %); V3 (51.44 %) and (29.35 %) was higher when compared to V1 (22.17 %) and (3.62 %). The swelling power of V1 observed at 60 °C (0.85 %) and 95 °C (8.64 %) were significantly different from V2 at 60 °C (4.97 %) and 95 °C (7.66 %) and that of V3 at 60 °C (5.82 %) and 95 °C (7.5 %). Significance difference in water solubility (7.62 %) and absorption capacity (6.11 %) was noted in V3 when compared with V1 and V2 owing to amylose/amylopectin content. Increase in water solubility and absorption capacity along with decrease in swelling power of V2 and V3 was noted due to hydrolytic and thermal process. RS obtained from hydrolysis showed a reduction in viscosity, indicating the rupture of starch molecules. The viscosity was found to be inversely proportional to the RS content in the sample. The thermal properties of RS increased due to the retrogradation and recrystallization (P < 0.05).

  4. The kinetics of the acetylation of gelatinised potato starch

    de Graaf, R.A.; Broekroelofs, G.A.; Janssen, L.P.B.M.; Beenackers, A.A C M


    The reaction rates, in the base-catalysed acetylation of gelatinised aqueous starch (4 wt%), by vinylacetate (ViAc), were investigated in a semibatch reactor at temperatures ranging from 20 to 50 degrees C. The desired starch acetylation reaction is accompanied by an undesired parallel base-catalyse

  5. Genome mining for new α-amylase and glucoamylase encoding sequences and high level expression of a glucoamylase from Talaromyces stipitatus for potential raw starch hydrolysis.

    Xiao, Zhizhuang; Wu, Meiqun; Grosse, Stephan; Beauchemin, Manon; Lévesque, Michelle; Lau, Peter C K


    Mining fungal genomes for glucoamylase and α-amylase encoding sequences led to the selection of 23 candidates, two of which (designated TSgam-2 and NFamy-2) were advanced to testing for cooked or raw starch hydrolysis. TSgam-2 is a 66-kDa glucoamylase recombinantly produced in Pichia pastoris and originally derived for Talaromyces stipitatus. When harvested in a 20-L bioreactor at high cell density (OD600 > 200), the secreted TSgam-2 enzyme activity from P. pastoris strain GS115 reached 800 U/mL. In a 6-L working volume of a 10-L fermentation, the TSgam-2 protein yield was estimated to be ∼8 g with a specific activity of 360 U/mg. In contrast, the highest activity of NFamy-2, a 70-kDa α-amylase originally derived from Neosartorya fischeri, and expressed in P. pastoris KM71 only reached 8 U/mL. Both proteins were purified and characterized in terms of pH and temperature optima, kinetic parameters, and thermostability. TSgam-2 was more thermostable than NFamy-2 with a respective half-life (t1/2) of >300 min at 55 °C and >200 min at 40 °C. The kinetic parameters for raw starch adsorption of TSgam-2 and NFamy-2 were also determined. A combination of NFamy-2 and TSgam-2 hydrolyzed cooked potato and triticale starch into glucose with yields, 71-87 %, that are competitive with commercially available α-amylases. In the hydrolysis of raw starch, the best hydrolysis condition was seen with a sequential addition of 40 U of a thermostable Bacillus globigii amylase (BgAmy)/g starch at 80 °C for 16 h, and 40 U TSgam-2/g starch at 45 °C for 24 h. The glucose released was 8.7 g/10 g of triticale starch and 7.9 g/10 g of potato starch, representing 95 and 86 % of starch degradation rate, respectively.

  6. Preparation and characterization of potato starch nanocrystal reinforced natural rubber nanocomposites.

    Rajisha, K R; Maria, H J; Pothan, L A; Ahmad, Zakiah; Thomas, S


    Potato starch nanocrystals were found to serve as an effective reinforcing agent for natural rubber (NR). Starch nanocrystals were obtained by the sulfuric acid hydrolysis of potato starch granules. After mixing the latex and the starch nanocrystals, the resulting aqueous suspension was cast into film by solvent evaporation method. The composite samples were successfully prepared by varying filler loadings, using a colloidal suspension of starch nanocrystals and NR latex. The morphology of the nanocomposite prepared was analyzed by field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM). FESEM analysis revealed the size and shape of the crystal and their homogeneous dispersion in the composites. The crystallinity of the nanocomposites was studied using XRD analysis which indicated an overall increase in crystallinity with filler content. The mechanical properties of the nanocomposites such as stress-strain behavior, tensile strength, tensile modulus and elongation at break were measured according to ASTM standards. The tensile strength and modulus of the composites were found to improve tremendously with increasing nanocrystal content. This dramatic increase observed can be attributed to the formation of starch nanocrystal network. This network immobilizes the polymer chains leading to an increase in the modulus and other mechanical properties.

  7. Synthesis and characterization of carboxymethyl potato starch and its application in reactive dye printing.

    Zhang, Bing; Gong, Honghong; Lü, Shaoyu; Ni, Boli; Liu, Mingzhu; Gao, Chunmei; Huang, Yinjuan; Han, Fei


    Carboxymethyl potato starch (CMPS) was synthesized with a simple dry and multi-step method as a product of the reaction of native potato starch and monochloroacetic acid in the presence of sodium hydroxide. The influence of the molar ratio of sodium hydroxide to anhydroglucose unit, the volume of 95% (v/v) ethanol, the rotation rate of motor driven stirrer and the reaction time for degree of substitution (DS) were evaluated. The product was characterized by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and X-ray diffractometry (XRD). FTIR spectrometry showed new bonds at 1618 and 1424 cm⁻¹ when native starch underwent carboxymethylation. SEM pictures showed that the smooth surface of native starch particles was mostly ruptured. XRD revealed that starch crystallinity was reduced after carboxymethylation. The viscosity of the mixture paste of carboxymethyl starch and sodium alginate (SA) was measured using a rotational viscometer. In addition, the applied effect of mixed paste in reactive dye printing was examined by assessing the fabric stiffness, color yield and sharp edge to the printed image in comparison with SA. And the results indicated that the mixed paste could partially replace SA as thickener in reactive dye printing. The study also showed that the method was low cost and eco-friendly and the product would have an extensive application in reactive dye printing. Copyright © 2012 Elsevier B.V. All rights reserved.

  8. A new generation of starch products as excipient in pharmaceutical tablets .1. Preparation and binding properties of high surface area potato starch products

    Wierik, GHPT; ArendsScholte, AW; Eissens, AC; Lerk, CF


    A new pharmaceutical excipient with a high binding capacity was prepared from potato starch by enzymatic degradation, followed by suitable dehydration of the precipitated and filtered retrograded starch to produce high specific surface area products. Thermal dehydration methods like drying at room o

  9. Production of ethanol by raw starch hydrolysis and fermentation of damaged grains of wheat and sorghum

    Suresh, K.; Kiransree, N.; Venkateswar Rao, L. [Osmania Univ., Hyderabad (India). Dept. of Microbiology


    The simultaneous saccharification and fermentation was used to produce ethanol from raw starch of damaged quality wheat and sorghum grains by utilising crude amylase preparation from B. subtilis VB2 and an amylolytic yeast strain S. cerevisiae VSJ4. Various concentrations of damaged wheat and sorghum starch from 10% to 30%W/V were used and 25% was found to be optimum for damaged wheat and sorghum starch yielding 4.40%V/V and 3.50%V/V ethanol respectively. Whereas 25% raw starch of fine quality wheat and sorghum grains gave an yield of 5.60%V/V and 5.00%V/V respectively. The process was carried out at 35 C, 5.8 pH and 200 rpm for 4 days. (orig.) With 2 figs., 4 tabs., 14 refs.

  10. Purification and properties of a novel raw starch degrading cyclomaltodextrin glucanotransferase from Bacillus firmus.

    Gawande, B N; Goel, A; Patkar, A Y; Nene, S N


    A novel raw starch degrading cyclomaltodextrin glucanotransferase (CGTase; E.C., produced by Bacillus firmus, was purified to homogeneity by ultrafiltration, affinity and gel filtration chromatography. The molecular weight of the pure protein was estimated to be 78,000 and 82,000 Da, by SDS-PAGE and gel filtration, respectively. The pure enzyme had a pH optimum in the range 5.5-8.5. It was stable over the pH range 7-11 at 10 degrees C, and at pH 7.0 at 60 degrees C. The optimum temperature for enzyme activity was 65 degrees C. In the absence of substrate, the enzyme rapidly lost its activity above 30 degrees C. K(m) and kcat for the pure enzyme were 1.21 mg/ml and 145.17 microM/mg per minute respectively, with soluble starch as the substrate. For cyclodextrin production, tapioca starch was the best substrate used when gelatinized, while wheat starch was the best substrate used when raw. This CGTase could degrade raw wheat starch very efficiently; up to 50% conversion to cyclodextrins was obtained from 150 g/l starch without using any additives. The enzyme produced alpha-, beta- and gamma-cyclodextrins in the ratio of 0.2:9.2:0.6 and 0.2:8.6:1.2 from gelatinized tapioca starch and raw wheat starch with 150 g/l concentration respectively, after 18 h incubation.

  11. Improvement of raw starch digestibility by ion-beam mutation of Aspergillus awamori

    Amsal, Aryanti [National Atomic Energy Agency, Jakarta (Indonesia); Takigami, Machiko; Ito, Hitoshi


    Aspergillus awamori possess the ability to express raw starch digestibility. For the effective utilization of starchy crops produced in South-Asian countries, it is important to achieve the digestion of raw starchs for industrial fermentation process. In this study, higher ratio of mutant strains of Aspergillus awamori IFO4033 were isolated by irradiation of C{sup 5+} ion-beam on freeze dried spores with improvement of enzyme production for two-to threefold in the extracellular {alpha}-amylase compared with gamma-irradiation. The digestibility of raw starch from cassava, sago and sukun increased remarkably about two-to threefold by some mutant strains obtained from irradiation of C{sup 5+} ion-beam. (author)

  12. Transcriptome Analysis Suggests That Starch Synthesis May Proceed via Multiple Metabolic Routes in High Yielding Potato Cultivars

    Kaminski, Kacper Piotr; Høgh Petersen, Annabeth; Sønderkær, Mads


    Background: Glucose-6-phosphate is imported into the amyloplast of potato tubers and thought to constitute the precursor for starch synthesis in potato tubers. However, recently it was shown that glucose-1-phosphate can also be imported into the amyloplast and incorporated into starch via an ATP...... independent mechanism under special conditions. Nonetheless, glucose 6-phosphate is believed to be the quantitatively important precursor for starch synthesis in potato. Principal Finding: Potato tubers of the high yielding cv Kuras had low gene expression of plastidial phophoglucomutase (PGM) and normal...... to expectations, this combination lead to a higher level of intracellular glucose-1-phosphate (G1P) in Kuras suggesting that G1P is directly imported into plastids and can be quantitatively important for starch synthesis under normal conditions in high yielding cultivars. Significance: This could open entirely...


    Gulam Rabbani


    Full Text Available In the present study Tapioca sago starch was employed as a disintegrating agent in Chloroquine based tablets at concentration of 5–15% w/w. Properties of the starch were evaluated for angle of repose, bulk density, tapped density, carr’s compressibility index, hausner’s ratio, hydration capacity and swelling capacity. The granules were evaluated for moisture content, angle of repose, bulk density and tapped density, carr’s compressibility index and hausner’s ratio. The tablets were evaluated for thickness, weight variation, crushing strength, friability, disintegration time and dissolution profiles. Batches of tablets containing equivalent concentration of potato starch were employed as standard. Results obtained indicate that as a disintegrant Tapioca sago starch showed comparable results in Chloroquine phosphate tablets with the standard.

  14. Transcriptome analysis suggests that starch synthesis may proceed via multiple metabolic routes in high yielding potato cultivars.

    Kacper Piotr Kaminski

    Full Text Available BACKGROUND: Glucose-6-phosphate is imported into the amyloplast of potato tubers and thought to constitute the precursor for starch synthesis in potato tubers. However, recently it was shown that glucose-1-phosphate can also be imported into the amyloplast and incorporated into starch via an ATP independent mechanism under special conditions. Nonetheless, glucose-6-phosphate is believed to be the quantitatively important precursor for starch synthesis in potato. PRINCIPAL FINDING: Potato tubers of the high yielding cv Kuras had low gene expression of plastidial phophoglucomutase (PGM and normal levels of transcripts for other enzymes involved in starch metabolism in comparison with medium and low yielding cultivars as determined by DeepSAGE transcriptome profiling. The decrease in PGM activity in Kuras was confirmed by measuring the enzyme activity from potato tuber extracts. Contrary to expectations, this combination lead to a higher level of intracellular glucose-1-phosphate (G1P in Kuras suggesting that G1P is directly imported into plastids and can be quantitatively important for starch synthesis under normal conditions in high yielding cultivars. SIGNIFICANCE: This could open entirely new possibilities for metabolic engineering of the starch metabolism in potato via the so far uncharacterized G1P transporter. The perspectives are to increase yield and space efficiency of this important crop. In the light of the increasing demands imposed on agriculture to support a growing global population this presents an exciting new possibility.

  15. Study on the physicochemical properties of purple sweet potato starch%紫薯淀粉理化性质的研究

    单珊; 周惠明; 朱科学


    紫薯富含硒元素和花青素,已广泛应用于食品加工.淀粉是紫薯的主要成分,其理化特性对紫薯加工品质有重要的影响.以川山紫鲜薯为原料制备紫薯淀粉,通过对比研究表明:薯类淀粉中紫薯淀粉糊化温度高,热稳定性和凝胶性好;而膨润性与溶解性差,透明度低,易回生.%Purple sweet potato (PSP) is rich in selenium and anthocyanins, which has been widely used in food processing.The physicochemical properties of PSP starch have a significant impact on PSP processing quality. Using PSP(Chuanshanzi)as raw material to produce PSP starch, compared with other kinds of potato starches, the results showed that PSP starch had a higher gelatinization temperature, better thermal stability and gel strength, but was poorer in the properties of swelling and solubility and transparency, and was apt to retrogradation.

  16. Effect of the incorporation of antimicrobial/antioxidant proteins on the properties of potato starch films.

    Moreno, Olga; Atarés, Lorena; Chiralt, Amparo


    Glycerol plasticized potato starch films containing bioactive proteins (lactoferrin (LF) and/or lysozyme (LZ), at 0.1 and 0.2 ratio with respect to starch) were obtained by casting method and characterized as to their microstructural, thermal and physical (water content, mechanical, water and oxygen barrier, optical) properties. The bioactive properties, named antioxidant and antimicrobial, of the proteins and the films were also characterized. The incorporation of proteins affected the structural and physical properties of potato starch films, while modifying their thermal behavior and increasing the glass transition temperature. Both proteins showed a certain degree of compatibility with starch chains through the bond formations (increase in Tg), while a part is separated and migrates to the film surface. Their incorporation, especially that of lactoferrin, greatly increased the film's brittleness, regardless of the films water content, although they enhance the water vapor and oxygen barrier properties, whatever the age of the film. Protein also reduced the film's transparency and gloss, while lactoferrin induced color changes. The thermal degradation of blend films and isolated proteins occurred at temperatures of over 250°C, which means that blend starch films can be thermoprocessed, according to their thermoplastic properties and following the usual practices of the plastics industries. A synergistic antimicrobial action against Escherichia coli and coliforms was observed when both LZ and LF were simultaneously applied. Both of these exhibited antioxidant capacity.

  17. Fitting of different models for water vapour sorption on potato starch granules

    Czepirski, L.; Komorowska-Czepirska, E.; Szymońska, J.


    Water vapour adsorption isotherms for native and modified potato starch were investigated. To obtain the best fit for the experimental data several models based on the BET approach were evaluated. The hypothesis that water is adsorbed on the starch granules at the primary and secondary adsorption sites as well as a concept considering the adsorbent fractality were also tested. It was found, that the equilibrium adsorption points in the examined range of relative humidity (0.03-0.90) were most accurately predicted by using a three-parameter model proposed by Kats and Kutarov.

  18. Shape-memory effect in amorphous potato starch: The influence of local orders and paracrystallinity.

    Chevigny, Chloé; Foucat, Loïc; Rolland-Sabaté, Agnès; Buléon, Alain; Lourdin, Denis


    In this paper, a detailed characterization of the mechanisms at the origin of the shape-memory effect in amorphous potato starch is presented. Using different treatments (annealing) and preparation methods (hot casting and extrusion), the local structures responsible for the shape-memory were disrupted, as evidenced in the first part of the article detailing the macroscopic properties: mechanical, calorimetric and shape-memory. In the second part the macromolecular scale is investigated using X-rays diffraction and CP-MAS NMR, and thus allows making the link between the structural differences and the macroscopic properties. Finally we discuss the origin of shape-memory in amorphous starch.

  19. Effect of thermal treatment on potato starch evidenced by EPR, XRD and molecular weight distribution.

    Bidzińska, Ewa; Michalec, Marek; Pawcenis, Dominika


    Effect of heating of the potato starch on damages of its structure was investigated by quantitative electron paramagnetic resonance (EPR) spectroscopy, X-ray diffraction and determination of the molecular weight distribution. The measurements were performed in the temperature range commonly used for starch modifications optimizing properties important for industrial applications. Upon thermal treatment, because of breaking of the polymer chains, diminishing of the average molecular weights occurred, which significantly influences generation of radicals, evidenced by EPR. For the relatively mild conditions, with heating parameters not exceeding temperature 230 °C and time of heating equal to 30 min a moderate changes of both the number of thermally generated radicals and the mean molecular weight of the starch were observed. After more drastic thermal treatment (e.g. 2 h at 230 °C), a rapid increase in the radical amount occurred, which was accompanied by significant reduction of the starch molecular size and crystallinity. Experimentally established threshold values of heating parameters should not be exceeded in order to avoid excessive damages of the starch structure accompanied by the formation of the redundant amount of radicals. This requirement is important for industrial applications, because significant destruction of the starch matrix might annihilate the positive influence of the previously performed intentional starch modification.

  20. Research on zinc fortified potato starch and on its use in dessert production

    Hanna Śmigielska


    Full Text Available Background. Modified potato starch is used as a thickener in foods or as a dessert component. Modification by oxidizing causes production of carboxyl radicals, which can bind elements in the coordination manner, inside starch granules. Zinc is one of the most essential microelements in the human body, and therefore the objective of our research was to determine the level of zinc adsorption from modified oxidized starch, to examine the changes in the starch’s functional properties and the possibilities of using the starch for manufacturing dry mixes of milk desserts such as puddings. Material and methods. The adsorption efficiency was examined with the Varian AAS atomic absorption spectrometer. The colour parameter was examined by Chroma Meter CR-300 Minolta and the viscosity of 3.3% of starch gels by Brabender viscosimeter. The organoleptic tested was determined in pudding prepared with fortified starch. Results. Result of microelement adsorption it ranges from 49% to 84%, depending on concentration of salt used for adsorption. The colour of preparations with zinc did not show significant differences, while their viscosity was variable and higher from the viscosity of marketed pudding starch. Results were analysed and the recipe for zinc fortified pudding was prepared. Conclusions. The best organoleptic properties were described for the dessert for which one portion contains approx. 7.5 mg of zinc, which is 50% RDA for an adult person.  

  1. Effect of various initiators on molar mass determination of hydrolyzed potato starch-acrylamide graft copolymers

    Đorđević Suzana


    Full Text Available This study is concerned with synthesis, characterization and properties of graft copolymer produced from hydrolyzed potato starch and acrylamide using various initiators (azobisisobutyronitrile, potassium persulfate and benzoyl peroxide. Starch hydrolysis was performed in order to reduce molecular mass. Acrylamide was grafted on shorter starch macromolecules creating side branches on the main chain resulting in a product that could be used in textile finishing more successfully. Various initiators were used, primarily, to produce graft monomer on the starch and also to obtain thinner or thicker packaging of side chains that can have a great influence on the behavior of textile yarns impregnated with these copolymers. Benzoyl peroxide, as initiator, proved to be very successful in grafting of acrylamide on hydrolyzed starch, in terms of yield, graft percentage and efficiency results. Grafting in the presence of azobisisobutyronitrile and potassium persulfate as initiators has slightly better monomer to polymer conversion values. FTIR spectra of hydrolyzed and grafted starch confirm by their characteristic bands that grafting was successful. Residual amounts of monomer in copolymer and molar mass distribution were determined by chromatography. Results show that the highest quantity of monomer is found in the sample of hydrolyzed starch grafted in the presence of potassium persulfate. Molar masses of hydrolysate and copolymer show differences ranging from 1∙102 to 2∙107 g/mol. Results of sizing using grafted starch show that sized yarns had higher strength (tenacity and lower elongation. Grafted hydrolyzed starch, as an agent for cotton yarn sizing, gives better results than non grafted starch, especially regarding sizing uniformity, yarn mechanical parameters and easier removal in following desizing process.

  2. Alcohol fermentation from sago starch granules using raw sago starch digesting amylase from Penicillum brunneum No. 24 and Saccharomyces cerevisaiae No. 33

    Haska, Nadirman (Hiroshima Univ., Kagamiyama (Japan). Lab. of Microbial Biochemistry); Ohta, Yoshiyuki (Hiroshima Univ., Kagamiyama (Japan). Lab. of Microbial Biochemistry)


    Treatment of the sago starch granules before incubation with the enzyme by heating to below gelatinization temperature at low pH condition was effective in improving the hydrolysis. Glucose could be produced from treated (at 60 C, pH 2.0) sago starch granules using the raw sago starch digesting amylase from our strain. Alcohol fermentation from the treated sago starch granules using the raw sago starch digesting amylase from Penicillium brunneum and a strain of yeast, Saccharomyces cerevisiae No. 33 could produce ethanol under incubation conditions of 35 C, pH 4.8. Addition of yeast and an extra half dose of enzyme after 24 h enzyme reaction was sufficient to continue starch hydrolysis during fermentation. This condition resulted in a conversion of sago starch to ethanol at a rate of about 44% in 72 h culture time. (orig.)

  3. Substitution patterns in methylated potato starch as revealed from the structure and composition of fragments in enzymatic digests

    Steeneken, P.A.M.; Tas, A.C.; Woortman, A.J.J.; Sanders, P.; Mijland, P.J.H.C.; Weijs,


    The effect of the granule structure on the methylation of starch was investigated by comparing the substitution patterns of potato starch methylated in granular suspension and in solution to DS 0.3. Substitution patterns were analyzed by successive digestion with α-amylase and amyloglucosidase,

  4. 超声与酸协同水解马铃薯淀粉研究%Study on potato starch hydrolysis under combination of ultrasound and acid

    胡爱军; 李立; 郑捷; 孟欣; 安莉莉; 卢静


    以马铃薯淀粉为原料,在超声作用下酸水解制备马铃薯改性淀粉。研究了盐酸添加量、超声温度、超声时间、超声功率对马铃薯淀粉酸解的影响,在单因素实验的基础上进行了正交实验。结果表明,超声作用下酸解马铃薯淀粉的适宜工艺参数为盐酸添加量7%,超声温度55℃,超声时间75 min,超声功率600 W。且超声协同酸改性的马铃薯淀粉峰值黏度下降92.07%。对比无超声作用的酸解淀粉,有超声作用的酸解淀粉黏度降低14.63%。因此,超声作用明显促进了马铃薯淀粉的酸解改性。%With potato starch as raw materia, modified potato starch was prepared by acid hydrolysis under ultrasound. The effects of hydrochloric acid dosage, temperature, time, and ultrasound power were investigated. Based on above investigations, an orthogonal experiment was carried out. The result showed that the optimal technological conditions of acid-hydrolyzed potato starch preparation with ultrasound were as follows: hydrochloric acid at 7%, ultrasonic temperature at 55 ℃ , ultrasonic time at 75 min, ultrasonic power at 600 W. And the peak value of viscosity of potato starch under the combination of acid and ultrasound showed a decrease of 92.07%. With ultrasound, the viscosity of acid-modified starch decreased 14.63% than that without ultrasound. Obviously, ultrasound promoted the acid hydrolysis of potato starch.

  5. Application of High Temperature Modified Potato Starch in Sausage Products%高温变性后的马铃薯淀粉在灌肠制品中的应用

    穆静; 郭雪松


    [Objective] To study the changes in the physiochemical properties of potato starch treated by high temperature, and its impact on the hardness, elasticity and chewing of sausage products. [ Method ] The potato starch was determined by RVA viscosity determinator and TMS-Pro texture analyzer. [ Result ] Apart from the fried potato starch, the viscosity stability of boiled and barked potato starch all enhanced, their paste stability was better then raw starch. [Conclusion] Adding modified potato starch instead of natural starch into sausage could improve the elasticity and adhesiveness of sausage, reduce the hardness and chewiness, and significantly improve the texture properties of sausage.%[目的]研究不同高温处理后,马铃薯淀粉理化性质的变化,及其改性后对灌肠制品硬度、弹性、咀嚼性等性质的影响.[方法]采用RVA黏度测定仪、TMS-Pro物性分析仪等对高温处理后的马铃薯淀粉进行测定.[结果]除油炸淀粉外,蒸煮、焙烤淀粉的黏度稳定性增加,成糊稳定性好于原淀粉.[结论]用改性的马铃薯淀粉代替天然淀粉添加到香肠中,明显提高了香肠的弹性和黏聚性,降低了硬度和咀嚼性,对香肠的质构特性有明显改善.

  6. Hydration properties and phosphorous speciation in native, gelatinized and enzymatically modified potato starch analyzed by solid-state MAS NMR

    Larsen, Flemming H.; Kasprzak, Miroslaw Marek; Lærke, Helle Nygaard


    Hydration of granular, gelatinized and molecularly modified states of potato starch in terms of molecular mobility were analyzed by 13C and 31P solid-state MAS NMR. Gelatinization (GEL) tremendously reduced the immobile fraction compared to native (NA) starch granules. This effect was enhanced....... Comparative analysis of wheat and waxy maize starches demonstrated that starches were similar upon gelatinization independent of botanical origin and that the torsion angles of the glycosidic linkages were averages of the crystalline A and B type structures. In starch suspension phosphorous in immobile...

  7. Thermodynamic and structural properties of tuber starches from transgenic potato plants grown in vitro and in vivo.

    Wasserman, Luybov A; Sergeev, Andrey I; Vasil'ev, Viktor G; Plashchina, Irina G; Aksenova, Nina P; Konstantinova, Tatyana N; Golyanovskaya, Svetlana A; Sergeeva, Lidiya I; Romanov, Georgy A


    Potato plants harboring Phytochrome B (PHYB) gene from Arabidopsis thaliana or rol genes from Agrobacterium rhizogenes were used to study the effect of transgene expression on structure and properties of starch in tubers. Thermodynamic characteristics of starch (melting temperature, enthalpy of melting, thickness of crystalline lamellae) were shown to be variable depending on the transgene expression and plant culturing mode: in vitro or in soil. The expression of rolB or rolC genes in in vitro cultured plants evoked opposite effects on starch melting temperature and crystalline lamellae thickness. AtPHYB or rolB expression in the soil-grown potato led to the formation of more defective or more ordered starch structures, respectively, in comparison with starches of the same lines grown in vitro. On the whole, our study revealed genotype-dependent differences between starches extracted from tubers of in vitro or in vivo grown plants.

  8. Large Scale Magnetic Separation of Solanum tuberosum Tuber Lectin from Potato Starch Waste Water

    Safarik, Ivo; Horska, Katerina; Martinez, Lluis M.; Safarikova, Mirka


    A simple procedure for large scale isolation of Solanum tuberosum tuber lectin from potato starch industry waste water has been developed. The procedure employed magnetic chitosan microparticles as an affinity adsorbent. Magnetic separation was performed in a flow-through magnetic separation system. The adsorbed lectin was eluted with glycine/HCl buffer, pH 2.2. The specific activity of separated lectin increased approximately 27 times during the isolation process.

  9. 马铃薯能生食吗?%Can Potato Be Eaten Raw?

    曾凡逵; 周添红


    马铃薯营养丰富,钾和维生素C含量都很高。很多蔬菜既可以生食也可以煮熟后食用。通常,生食的蔬菜鲜嫩多汁且口感清新。然而有些蔬菜很少用来生食,马铃薯就是其中一种。马铃薯可以生食,但带有一点苦味,因此很少有人生食马铃薯。生的马铃薯其内含有的蛋白酶抑制剂具有潜在的治疗癌症的作用,但生食马铃薯的风险也很大,会导致难消化、产气和腹胀、食源性疾病和中毒等现象。%Potatoes are an excellent source of potassium and vitamin C. Many vegetables are commonly consumed raw, as wel as cooked. In general, raw vegetables are bright in color, juicy and fresh flavored. However, there are some vegetables that are seldom eaten raw. Potato is one of those. Although they can be eaten raw, their starchy texture and slight bitterness are unappealing to most. Potato protease inhibitors have the potential application of treatment for cancer, but the risks of eating raw potatoes are present, including indigestibility, gas and bloating, foodborne il ness, and toxicity.

  10. Influence of glycerol on the melting of potato starch

    Vliegenthart, J.F.G.; Soest, J.J.G. van; Bezemer, R.C.; Wit, D. de


    The gelatinization and melting of granular and recrystallized starch have been studied in the presence of low and high levels of glycerol or water by differential scanning calorimetry. The gelatinization onset temperature is increased in the presence of glycerol, whereas the excess gelatinization

  11. Influence of glycerol on the melting of potato starch

    Soest, van J.J.G.; Bezemer, R.C.; Wit, de D.; Viiegenthart, J.F.G.


    The gelatinization and melting of granular and recrystallized starch have been studied in the presence of low and high levels of glycerol or water by differential scanning calorimetry. The gelatinization onset temperature is increased in the presence of glycerol, whereas the excess gelantinization

  12. The raw starch binding domain of cyclodextrin glycosyltransferase from Bacillus circulans strain 251

    Penninga, Dirk; Veen, Bart A. van der; Knegtel, Ronald M.A.; Hijum, Sacha A.F.T. van; Rozeboom, Henriëtte J.; Kalk, Kor H.; Dijkstra, Bauke W.; Dijkhuizen, Lubbert


    The E-domain of cyclodextrin glycosyltransferase (CGTase) (EC from Bacillus circulans strain 251 is a putative raw starch binding domain. Analysis of the maltose-dependent CGTase crystal structure revealed that each enzyme molecule contained three maltose molecules, situated at contact

  13. Polarimetric Determination of Starch in Raw Materials and Discharged Waste from Beer Production

    Anca Farcas


    Full Text Available Brewer’s spent grain (BGS is a by-product of thebrewing process, consisting of the solid fraction of barley malt remainingafter separation of worth. In this research, raw materials and discharged waste from beer production were evaluated on the basis of starch content, using Ewers polarimetric method.

  14. Polarimetric Determination of Starch in Raw Materials and Discharged Waste from Beer Production

    Anca Farcas; Maria Tofana; Sonia Socaci; Stancuta Scrob; Liana Salanta; Doinita Bors


    Brewer’s spent grain (BGS) is a by-product of thebrewing process, consisting of the solid fraction of barley malt remainingafter separation of worth. In this research, raw materials and discharged waste from beer production were evaluated on the basis of starch content, using Ewers polarimetric method.

  15. Preparation and characterization of bionanocomposite films based on potato starch/halloysite nanoclay.

    Sadegh-Hassani, Fatemeh; Mohammadi Nafchi, Abdorreza


    In this research casting method was used to prepare potato starch based bio-nanocomposite films with halloysite nanoclay as the reinforcing materials. The composition included potato starch with 40% (w/w) of a mixture of sorbitol/glycerol (weight ratio of 3 to 1as plasticizer) with nanoclay (0-5% w/w). The films were dried under controlled conditions. Physicochemical properties such as solubility in water, water absorption capacity (WAC), water vapour permeability (WVP), oxygen permeability, and mechanical properties of the films were measured. Results showed that by increasing the concentration of nanoclay, mechanical properties of films were improved. Tensile strength was increased from 7.33 to 9.82MPa, and elongation at break decreased from 68.0 to 44.0%. Solubility in water decreased from 35 to 23%, and heat seal strength increased from 375 to 580N/m. Also incorporation of clay nanoparticles in the structure of biopolymer decreased permeability of the gaseous molecules. In summary, addition of halloysite nanoclay, improve the barrier and mechanical properties of potato starch films and this bionanocomposites have high potential to be used for food packaging purposes. Copyright © 2014 Elsevier B.V. All rights reserved.

  16. Characterization of a bioflocculant from potato starch wastewater and its application in sludge dewatering.

    Guo, Junyuan; Zhang, Yuzhe; Zhao, Jing; Zhang, Yu; Xiao, Xiao; Wang, Bin; Shu, Bi


    A bioflocculant was produced by using potato starch wastewater; its potential in sludge dewatering and potato starch wastewater treatment was investigated. Production of this bioflocculant was positively associated with cell growth, and a highest value of 0.81 g/L was obtained. When incubated with this bioflocculant, dry solids (DS) and specific resistance to filtration (SRF) of typical wastewater activated sludge reached 20.8% and 3.9 × 10(12) m/kg, respectively, which were much better than the ones obtained with conventional chemical flocculants. Sludge dewatering was further improved when both the bioflocculant and conventional polyacrylamide (PAM) were used simultaneously. With potato starch wastewater, chemical oxygen demand (COD) and turbidity removal rates could reach 52.4 and 81.7%, respectively, at pH value of 7.5 when the bioflocculant dose was adjusted to 30 mg/L; from a practical standpoint, the removal of COD and turbidity reached 48.3 and 72.5%, respectively, without pH value adjustment.

  17. Effects of granule size of cross-linked and hydroxypropylated sweet potato starches on their physicochemical properties.

    Zhao, Jianwei; Chen, Zhenghong; Jin, Zhengyu; Buwalda, Piet; Gruppen, Harry; Schols, Henk A


    Sweet potato starch was modified by cross-linking, hydroxypropylation, and combined cross-linking and hydroxypropylation, and the starches were subsequently sieved to obtain differently sized granule fractions. The effects of granule size of native and modified sweet potato starch fractions and all fractions were investigated with respect to their physicochemical properties. The large-size granule fraction (27-30 μm) showed a 16-20% higher chemical phosphorylation and a 4-7% higher hydroxypropylation than the small-size granule fraction (14-16 μm). The large-size granule fractions of native and modified sweet potato starches showed lower transition temperatures (0.7-3.1 °C for peak temperature of gelatinization) and lower enthalpy changes (0.6-1.9 J/g) during gelatinization than the small-size granule fractions, making the sweet potato starch different from cereal starches. The large-size granule fraction of native starch showed a higher paste viscosity (78-244 cP) than the corresponding small-size granule fraction. In addition, cross-linking and hydroxypropylation affected the paste viscosity of the large-size granule fraction significantly more than that of the small-size granule fraction when compared to the corresponding parental starch fractions. The large-size granule fraction of native and dual-modified starches showed a lower syneresis after freeze-thaw treatments than the small-size granule fractions. The difference in swelling power between large- and small-size granule fractions was not significant. In general, the large-size granule fraction of sweet potato starch was more susceptible for cross-linking and hydroxypropylation and the physicochemical properties were changed to a higher extent compared to the corresponding small-size granule fraction.

  18. Simultaneous boosting of source and sink capacities doubles tuber starch yield of potato plants.

    Jonik, Claudia; Sonnewald, Uwe; Hajirezaei, Mohammad-Reza; Flügge, Ulf-Ingo; Ludewig, Frank


    An important goal in biotechnological research is to improve the yield of crop plants. Here, we genetically modified simultaneously source and sink capacities in potato (Solanum tuberosum cv. Desirée) plants to improve starch yield. Source capacity was increased by mesophyll-specific overexpression of a pyrophosphatase or, alternatively, by antisense expression of the ADP-glucose pyrophosphorylase in leaves. Both approaches make use of re-routing photoassimilates to sink organs at the expense of leaf starch accumulation. Simultaneous increase in sink capacity was accomplished by overexpression of two plastidic metabolite translocators, that is, a glucose 6-phosphate/phosphate translocator and an adenylate translocator in tubers. Employing such a 'pull' approach, we have previously shown that potato starch content and yield can be increased when sink strength is elevated. In the current biotechnological approach, we successfully enhanced source and sink capacities by a combination of 'pull' and 'push' approaches using two different attempts. A doubling in tuber starch yield was achieved. This successful approach might be transferable to other crop plants in the future.

  19. Mechanical properties of potato starch modified by moisture content and addition of lubricant

    Stasiak, Mateusz; Molenda, Marek; Horabik, Józef; Mueller, Peter; Opaliński, Ireneusz


    Laboratory testing was conducted to deliver a set of characteristics of structure and mechanical properties of pure starch and starch with an addition of a lubricant - magnesium stearate. Considerable influence of moisture content of potato starch was found in the case of density, parameters of internal friction, coefficients of wall friction and flowability. Elasticity was found to be strongly influenced by water content of the material. Addition of magnesium stearate affected density and parameters of flowability, internal friction and elasticity. Bulk density increased from 604 to 774 kg m-3 with decrease in moisture content of potato starch from 17 to for 6%. Addition of magnesium stearate resulted in approximately 10% decrease in bulk density. Angle of internal friction obtained for 10 kPa of consolidation stress decreased from 33 to 24º with increase in moisture content, and to approximately 22º with addition of the lubricant. With an increase of moisture content from 6 to 18% and with addition of the lubricant, the modulus of elasticity during loading decreased from approximately 1.0 to 0.1 MPa. Modulus of elasticity during unloading was found in the range from 19 to 42 MPa and increased with increase of moisture content and amount of lubricant.

  20. Effect of pulsed electric fields assisted acetylation on morphological, structural and functional characteristics of potato starch.

    Hong, Jing; Chen, Rujiao; Zeng, Xin-An; Han, Zhong


    Pulsed electric fields (PEF)-assisted acetylation of potato starch with different degree of substitution (DS) was prepared and effects of PEF strength, reaction time, starch concentration on DS were studied by response surface methodology. Results showed DS was increased from 0.054 (reaction time of 15 min) to 0.130 (reaction time of 60 min) as PEF strength increased from 3 to 5 kV/cm. External morphology revealed that acetylated starch with higher DS was aggravated more bulges and asperities. Fourier-transformed infrared spectroscopy confirmed the introduction of acetyl group through a band at 1730 cm(-1). The optimum sample (DS =0 .13) had lower retrogradation (39.1%), breakdown (155 BU) and setback value (149BU), while pasting temperature (62.2 °C) was slightly higher than non-PEF-assisted samples. These results demonstrated PEF treatment can be a potential and beneficial method for acetylation and achieve higher DS with shorter reaction time.

  1. SNPs in genes functional in starch-sugar interconversion associate with natural variation of tuber starch and sugar content of potato (Solanum tuberosum L.).

    Schreiber, Lena; Nader-Nieto, Anna Camila; Schönhals, Elske Maria; Walkemeier, Birgit; Gebhardt, Christiane


    Starch accumulation and breakdown are vital processes in plant storage organs such as seeds, roots, and tubers. In tubers of potato (Solanum tuberosum L.) a small fraction of starch is converted into the reducing sugars glucose and fructose. Reducing sugars accumulate in response to cold temperatures. Even small quantities of reducing sugars affect negatively the quality of processed products such as chips and French fries. Tuber starch and sugar content are inversely correlated complex traits that are controlled by multiple genetic and environmental factors. Based on in silico annotation of the potato genome sequence, 123 loci are involved in starch-sugar interconversion, approximately half of which have been previously cloned and characterized. By means of candidate gene association mapping, we identified single-nucleotide polymorphisms (SNPs) in eight genes known to have key functions in starch-sugar interconversion, which were diagnostic for increased tuber starch and/or decreased sugar content and vice versa. Most positive or negative effects of SNPs on tuber-reducing sugar content were reproducible in two different collections of potato cultivars. The diagnostic SNP markers are useful for breeding applications. An allele of the plastidic starch phosphorylase PHO1a associated with increased tuber starch content was cloned as full-length cDNA and characterized. The PHO1a-HA allele has several amino acid changes, one of which is unique among all known starch/glycogen phosphorylases. This mutation might cause reduced enzyme activity due to impaired formation of the active dimers, thereby limiting starch breakdown.

  2. SNPs in Genes Functional in Starch-Sugar Interconversion Associate with Natural Variation of Tuber Starch and Sugar Content of Potato (Solanum tuberosum L.)

    Schreiber, Lena; Nader-Nieto, Anna Camila; Schönhals, Elske Maria; Walkemeier, Birgit; Gebhardt, Christiane


    Starch accumulation and breakdown are vital processes in plant storage organs such as seeds, roots, and tubers. In tubers of potato (Solanum tuberosum L.) a small fraction of starch is converted into the reducing sugars glucose and fructose. Reducing sugars accumulate in response to cold temperatures. Even small quantities of reducing sugars affect negatively the quality of processed products such as chips and French fries. Tuber starch and sugar content are inversely correlated complex traits that are controlled by multiple genetic and environmental factors. Based on in silico annotation of the potato genome sequence, 123 loci are involved in starch-sugar interconversion, approximately half of which have been previously cloned and characterized. By means of candidate gene association mapping, we identified single-nucleotide polymorphisms (SNPs) in eight genes known to have key functions in starch-sugar interconversion, which were diagnostic for increased tuber starch and/or decreased sugar content and vice versa. Most positive or negative effects of SNPs on tuber-reducing sugar content were reproducible in two different collections of potato cultivars. The diagnostic SNP markers are useful for breeding applications. An allele of the plastidic starch phosphorylase PHO1a associated with increased tuber starch content was cloned as full-length cDNA and characterized. The PHO1a-HA allele has several amino acid changes, one of which is unique among all known starch/glycogen phosphorylases. This mutation might cause reduced enzyme activity due to impaired formation of the active dimers, thereby limiting starch breakdown. PMID:25081979

  3. Ultrasound Assisted Preparation of Cold Water Soluble Sweet Potato Starch%超声波辅助制备冷水可溶性甘薯淀粉

    成纪予; 庞林江; 陆国权


    Sweet potato starch was utilized as the raw material,and ethanol -alkali method assisted by ultra-sound was used to prepare cold water soluble sweet potato starch in the paper.The effects of starch concentration, ethanol concentration,sodium hydroxide dosage,ultrasonic power and ultrasonic time on the solubility of the final product were investigated.Based on the single factor experiments results,the preparation conditions were optimized through the Box -Behnken response surface method.The best preparation conditions were starch concentration 4.0 g/100 mL,ethanol concentration 81%,ultrasonic power 300 W and ultrasonic time 22 min.The validated solubility of cold water soluble sweet potato starch reached 96.38%,and the relative error between estimating data of regressive model and actual data was less than 1% on the best extraction conditions.The results indicated that ultrasound had application prospects in the preparation of cold water soluble sweet potato starch.%以甘薯淀粉为原料,采用超声波辅助乙醇碱法制备颗粒状冷水可溶性甘薯淀粉,系统研究了淀粉乳浓度、乙醇浓度、碱用量、超声波功率和超声波时间对冷水可溶淀粉溶解度的影响。在单因素试验基础上,通过 Box -Behnken 响应面优化制备条件,得到最佳的反应条件为:淀粉乳质量浓度4.0 g/100 mL,乙醇体积分数81%,超声波功率为300 W,超声时间22 min。经验证,在最佳条件下,所制得的甘薯淀粉溶解度达到96.38%,回归模型预测值与实测值的相对误差<1%。研究结果表明,超声波在制备冷水可溶性甘薯淀粉方面有一定的应用前景。

  4. Ion Dynamics Study of Potato Starch + Sodium Salts Electrolyte System

    Tuhina Tiwari


    Full Text Available The effect of different anions, namely, SCN−, I−, and ClO4−, on the electrical properties of starch-based polymer electrolytes has been studied. Anion size and conductivity are having an inverse trend indicating systems to be predominantly anionic conductor. Impact of anion size and multiplet forming tendency is reflected in number of charge carriers and mobility, respectively. Ion dynamics study reveals the presence of different mechanisms in different frequency ranges. Interestingly, superlinear power law (SLPL is found to be present at <5 MHz frequency, which is further confirmed by dielectric data.

  5. Study on physicochemical properties of resistant starch prepared from sweet potato starch%甘薯抗性淀粉理化性质研究

    张芸; 李小定; 郑政东; 何芒芒; 李杰; 曲智雅; 朱少华; 刘蒙; 曲露


    采用酶法结合超声波处理制备抗性淀粉,并分析其颗粒分布、晶体结构类型、淀粉分子结构、热特性等理化特性 结果表明,甘薯抗性淀粉颗粒分布、粒径大小、晶体结构、熔融温度明显不同于甘薯淀粉.甘薯抗性淀粉平均粒径、糊化峰值温度、终止温度大于甘薯淀粉;甘薯淀粉结晶结构表现为C型,甘薯抗性淀粉结晶结构表现为B型,酶解辅以超声波处理的方法可以制备高含量的抗性淀粉.%Sweet potato resistant starch were prepared by using enzymatic de - branching combined ultrasonic treatment,then partial physicochemical properties including particle size distribution, crystal structure, thermal properties were studied.Results showed that there were significant difference in the particle size distribution,mean diameter,crystal structure,and melt temperature between sweet potato resistant starch and sweet potato starch. The resistant starch exhibited significantly higher overall size, peak gelatinization temperature, conclusion temperature than sweet potato starch.X-ray diffraction patterns indicated that the crystal structure of native starch was C type and that the crystal structure of resistant starch was B type. Results showed that enzyme hydrolysis modification combined ultrasonic treatment could prepare high content of resistant starch.

  6. Biogas production from potato-juice, a by-product from potato-starch processing, in upflow anaerobic sludge blanket (UASB) and expanded granular sludge bed (EGSB) reactors

    Fang, Cheng; Boe, Kanokwan; Angelidaki, Irini


    In this study, the utilization of potato-juice, the organic by-product from potato-starch processing, for biogas production was investigated in batch assay and in high rate anaerobic reactors. The maximum methane potential of the potato-juice determined by batch assay was 470mL-CH4/g......L-CH4/gVS-added. The treatment of reactor effluent was also investigated. By acidification with sulfuric acid to pH lower than 5, almost 100% of the ammonia content in the effluent could be retained during the successive up-concentration process step. The reactor effluent could be up...

  7. Characterisation of cationic potato starch by asymmetrical flow field-flow fractionation. Influence of ionic strength and degree of substitution.

    Santacruz, Stalin


    The properties of a paper sheet depend on the absorption together with the physico-chemical properties of additives used in the paper processing. The effect of ionic strength and degree of substitution of cationic potato starch on the elution pattern of asymmetrical flow field-flow fractionation was analysed. The effect of starch derivatisation, in either dry or wet phase, was also investigated. Average molar mass showed no difference between the starches obtained from the two derivatisation processes. Apparent densities showed that dry cationic starch had higher density than wet cationic starch for a hydrodynamic radius between 50 and 100 nm. Elution times of native and three cationic starches increased when the ionic strength increased from 50 to 100mM. No differences in the molar mass among cationic starches with different degree of substitution suggested no degradation due to a derivatisation process. Large sample loads can be used at 100mM without overloading.

  8. Particle size and cholesterol content of a mayonnaise formulated by OSA-modified potato starch

    Shiva Ghazaei


    Full Text Available Egg yolk was partially replaced (0, 25, 50, 75, and 100% with octenyl succinic anhydride (OSA-modified potato starch in a reduced-fat mayonnaise formulation to curtail the problems associated with high cholesterol and induced allergic reactions. The physicochemical properties included parameters such as: pH, fat content, and emulsion stability of the formulations analyzed. The samples with 75% and 100% egg yolk substitute showed the maximum emulsion stability (>95% after two of months storage, and they were selected according to cholesterol content, particle size distributions, dynamic rheological properties, microstructure, and sensory characteristic. A significant reduction (84-97% in the cholesterol content was observed in the selected samples. Particle size analysis showed that by increasing the amount of OSA starch, the oil droplets with the peak size of 70 µm engulfed by this compound became larger. The rheological tests elucidated that in the absence of egg yolk, OSA starch may not result in a final product with consistent texture and that the best ratio of the two emulsifiers (OSA starch/egg yolk to produce stable reduced-fat, low cholesterol mayonnaise is 75/25. The microscopic images confirmed the formation of a stable cohesive layer of starch surrounding the oil droplets emulsified in the samples selected.

  9. The in vitro caecal fermentation of different starch sources in rabbits

    Kermauner, Ajda; Lavrenčič, Andrej


    The objective of our study was to extend the knowledge of microbial fermentation of starch in the rabbit caecum using the in vitro gas production technique. Different sources of starch (wheat and maize grain, raw and cooked potato) and different starch isolates (wheat, maize and potato starch) were incubated with inoculum, prepared from rabbit caecum content. The gas production parameters such as total potential gas production (parameter "B"), gas production till 10 h of incubation (Gas10), m...

  10. Peroxydisulfate initiated synthesis of potato starch-graft-poly(acrylonitrile under microwave irradiation


    Full Text Available Potato starch-graft-poly(acrylonitrile could be efficiently synthesized using small concentration of ammonium peroxydisulfate (0.0014M in aqueous medium under microwave irradiation. A representative microwave synthesized graft copolymer was characterized using Fourier Transform Infrared Spectroscopy, X-ray Diffraction, Scanning Electron Microscopy and Thermogravimetric Analysis. Under microwave conditions oxygen removal from the reaction vessel was not required and the graft copolymer was obtained in high yield using very small amount of ammonium peroxydisulfate, however using the same amount of ammonium peroxydisulfate (0.0014M on thermostatic water bath no grafting was observed up to 98°C (even in inert atmosphere. Raising the concentration of the initiator to 0.24 M resulted into 10% grafting at 50 °C but in inert atmosphere.The viscosity/shear stability of the grafted starch (aqueous solution and water/saline retention ability of the microwave synthesized graft copolymer were also studied and compared with that of the native potato starch.

  11. Decreased sucrose content triggers starch breakdown and respiration in stored potato tubers (Solanum tuberosum).

    Hajirezaei, Mohammad-Reza; Börnke, Frederik; Peisker, Martin; Takahata, Yasuhiro; Lerchl, Jens; Kirakosyan, Ara; Sonnewald, Uwe


    To change the hexose-to-sucrose ratio within phloem cells, yeast-derived cytosolic invertase was expressed in transgenic potato (Solanum tuberosum cv. Desirée) plants under control of the rolC promoter. Vascular tissue specific expression of the transgene was verified by histochemical detection of invertase activity in tuber cross-sections. Vegetative growth and tuber yield of transgenic plants was unaltered as compared to wild-type plants. However, the sprout growth of stored tubers was much delayed, indicating impaired phloem-transport of sucrose towards the developing bud. Biochemical analysis of growing tubers revealed that, in contrast to sucrose levels, which rapidly declined in growing invertase-expressing tubers, hexose and starch levels remained unchanged as compared to wild-type controls. During storage, sucrose and starch content declined in wild-type tubers, whereas glucose and fructose levels remained unchanged. A similar response was found in transgenic tubers with the exception that starch degradation was accelerated and fructose levels increased slightly. Furthermore, changes in carbohydrate metabolism were accompanied by an elevated level of phosphorylated intermediates, and a stimulated rate of respiration. Considering that sucrose breakdown was restricted to phloem cells it is concluded that, in response to phloem-associated sucrose depletion or hexose elevation, starch degradation and respiration is triggered in parenchyma cells. To study further whether elevated hexose and/or hexose-phosphates or decreased sucrose levels are responsible for the metabolic changes observed, sucrose content was decreased by tuber-specific expression of a bacterial sucrose isomerase. Sucrose isomerase catalyses the reversible conversion of sucrose into palatinose, which is not further metabolizable by plant cells. Tubers harvested from these plants were found to accumulate high levels of palatinose at the expense of sucrose. In addition, starch content decreased

  12. Hydrolysis of Raw Corn Starch Granules by Glucoamylase and Product Inhibition During the Hydrolysis

    WANG Jinpeng; ZENG Aiwu; LIU Zhen; YUAN Xigang; WU Shaomin


    Raw corn starch granules were hydrolysized by glucoamylase in a chemostat. The hydro-lysis of three different-sized granules shows that smaller granules undergo more hydrolyzation than larger ones. After 78 h, 97% of the granules was hydrolysized with diameter between 0.15 mm and 0.3 mm at 50 ℃. When corn starch concentration increased from 100 g/L to 250 g/L, the amount of reducing sugar produced was proportional to the initial substrate concentration and no substrate inhibition phenomenon appeared. In order to study the product inhibition exactly, the product from hydrolysis reaction itself was added into the hydrolysis system at the beginning of starch hydrolysis. Product inhibition with different quantities of product added were studied in the initial several hours, during which period enzyme inactivation could be neglected and product inhibition could be studied separately. The experiments indicate that product inhibition happens when the additional quantity exceeds 9.56 g/L.

  13. Production of raw cassava starch-degrading enzyme by Penicillium and its use in conversion of raw cassava flour to ethanol.

    Lin, Hai-Juan; Xian, Liang; Zhang, Qiu-Jiang; Luo, Xue-Mei; Xu, Qiang-Sheng; Yang, Qi; Duan, Cheng-Jie; Liu, Jun-Liang; Tang, Ji-Liang; Feng, Jia-Xun


    A newly isolated strain Penicillium sp. GXU20 produced a raw starch-degrading enzyme which showed optimum activity towards raw cassava starch at pH 4.5 and 50 °C. Maximum raw cassava starch-degrading enzyme (RCSDE) activity of 20 U/ml was achieved when GXU20 was cultivated under optimized conditions using wheat bran (3.0% w/v) and soybean meal (2.5% w/v) as carbon and nitrogen sources at pH 5.0 and 28 °C. This represented about a sixfold increment as compared with the activity obtained under basal conditions. Starch hydrolysis degree of 95% of raw cassava flour (150 g/l) was achieved after 72 h of digestion by crude RCSDE (30 U/g flour). Ethanol yield reached 53.3 g/l with fermentation efficiency of 92% after 48 h of simultaneous saccharification and fermentation of raw cassava flour at 150 g/l using the RCSDE (30 U/g flour), carried out at pH 4.0 and 40 °C. This strain and its RCSDE have potential applications in processing of raw cassava starch to ethanol.

  14. Effects of annealing on the pasting properties of potato and corn starches%韧化处理对马铃薯淀粉及玉米淀粉糊化性质的影响

    蒲华寅; 王乐; 黄峻榕; 杨婷


    The effects of annealing on the pasting and viscosity properties of potato and corn starches were studied by differential scanning calorimeter (DSC) and rapid viscosity analyzer (RVA) .The results showed that the onset temperature (To) of potato and corn starches in‐creased and the gelatinization peak narrowed with increasing annealing time ,especially for starch annealed for 3 h .The gelatinization enthalpy (ΔH) increased and then decreased with the increase in annealing time for the annealed starch .In addition ,potato starch annealed for 24 h showed a higher gelatinization enthalpy compared with its raw starch ,while the gelatini‐zation enthalpy of annealed corn starch was not higher than that of raw starch .After annea‐ling ,the pasting temperature increased and the peak viscosity decreased ,w hereas potato starch and corn starch showed an inverse varying pattern in trough viscosity and final viscosi‐ty .The onset temperature measured by DSC was lower than the pasting temperature meas‐ured by RVA ,which indicated that the crystalline structure was destroyed before the rising in viscosity during gelatinization .%利用差示扫描量热及快速黏度分析技术研究了韧化对马铃薯淀粉及玉米淀粉糊化热性质及黏度性质的影响。结果显示:随着韧化时间的增加,淀粉糊化起始温度(T o )增加,糊化峰变窄,且韧化前3 h变化较明显,韧化淀粉糊化焓先增大后减小,但马铃薯淀粉韧化24 h后焓值高于原淀粉,而玉米淀粉韧化后焓值均不高于原淀粉。韧化淀粉起糊温度增加,峰值黏度减小,但两种淀粉谷值黏度和最终黏度变化趋势相反。起始糊化温度低于起糊温度,证明淀粉糊化过程中黏度快速上升前结晶结构已遭到破坏。

  15. Study of quantitative interactions of potato and corn starch granules with ions in diluted solutions of heavy metal salts.

    Szymońska, Joanna; Molenda, Marcin; Wieczorek, Jerzy


    Interactions of potato and corn starch granules with ions in diluted solutions of silver, lead, copper or iron salts were investigated. It was shown experimentally that granules accumulated the cations in amounts depending on the granule structure and water content as well as a type of both metal and counter-ions present in solution. Potato starch retained almost three times more cations compared to corn starch what was proportional to the total phosphorous content in these starches. Quantity of milligrams of cations bound by 1g of starch was inversely correlated with the cation hydration. Ag(+), Pb(2+) and Cu(2+) were connected in stoichiometric amounts of moles to semicrystalline and amorphous parts of the granules. Fe(3+) ions were accumulated in higher than stoichiometric quantities mainly in granule amorphous regions. Metal ions penetrated into granules together with anions except nitrates which remained on surface of potato starch granules. Cations facilitated the starch thermal decomposition in accordance with values of their standard redox potentials. Nitrates supported this process only in the presence of base metal cations.

  16. Utilization of sorghum, rice, corn flours with potato starch for the preparation of gluten-free pasta.

    Ferreira, Sila Mary Rodrigues; de Mello, Ana Paula; de Caldas Rosa dos Anjos, Mônica; Krüger, Cláudia Carneiro Hecke; Azoubel, Patrícia Moreira; de Oliveira Alves, Márcia Aurelina


    The aim of this study was to evaluate the use of mixture of sorghum-rice-corn flour and potato starch in the development of gluten-free pasta for celiac disease patients. The experiment was designed according to simplex-lattice method and different types of gluten-free flours were used, such as sorghum, rice, corn, and potato starch. The fifteen formulations were subjected to sensory analysis (Mixed Structured Scale - MSS) and seven formulations were selected in respect to taste and grittiness. These formulations were subjected to Quantitative Descriptive Analysis (QDA), which evaluated the attributes: appearance, color, odor, hardness, elasticity, stickiness, grittiness, taste, residual bitterness and overall quality. Results showed significant difference in appearance, color and hardness. The formulations that showed the best sensory results were submitted to chemical analysis and cooking quality of pasta. It was observed that the best results for mixing is sorghum flour, rice flour and potato starch.

  17. Direct screening of libraries of yeast clones for alpha-amylase activity on raw starch hydrolysis.

    Wong, Dominic W S; Batt, Sarah B; Lee, Charles C; Robertson, George H


    High-throughput screening for high-activity barley alpha-amylase mutants expressed in Saccharomyces cerevisiae is hampered by the interference of reducing agents, particularly the glucose used in yeast growth media. The present investigation employed colorimetric and chemiluminescent detection systems that enable direct and rapid screening of activities on raw starch substrate. Active clones could be separated into two groups, based on high total activity or high specific activity.

  18. Repeated fermentation from raw starch using Saccharomyces cerevisiae displaying both glucoamylase and α-amylase.

    Yamakawa, Syun-ichi; Yamada, Ryosuke; Tanaka, Tsutomu; Ogino, Chiaki; Kondo, Akihiko


    A diploid yeast strain displaying both α-amylase and glucoamylase was developed for repeated fermentation from raw starch. First, the construct of α-amylase was optimized for cell surface display, as there have been no reports of α-amylase-displaying yeast. The modified yeast displaying both glucoamylase and α-amylase produced 46.5 g/l of ethanol from 200 g/l of raw corn starch after 120 h of fermentation, and this was 1.5-fold higher when compared to native α-amylase-displaying yeast. Using the glucoamylase and modified α-amylase co-displaying diploid strain, we repeated fermentation from 100g/l of raw starch for 23 cycles without the loss of α-amylase or glucoamylase activity. The average ethanol productivity and yield during repeated fermentation were 1.61 g/l/h and 76.6% of the theoretical yield, respectively. This novel yeast may be useful for reducing the cost of bio-ethanol production and may be suitable for industrial-scale bio-ethanol production.

  19. Preferential and rapid degradation of raw rice starch by an α-amylase of glycoside hydrolase subfamily GH13_37.

    Lei, Yin; Peng, Hui; Wang, Ying; Liu, Yuantao; Han, Fang; Xiao, Yazhong; Gao, Yi


    The α-amylase (AmyP) from a marine metagenomic library belongs to the recently classified glycoside hydrolase subfamily GH13_37. The degradation abilities of AmyP on a broad range of raw starch granules were examined at 40 °C and pH 7.5. It was found that AmyP is a raw starch-degrading enzyme, exhibiting a unique and remarkable ability to preferentially and very rapidly digest raw rice starch. The specific activity of raw rice starch was reached 118.5 ± 0.6 Umg(-1), which was much higher than that of other raw starches. The final hydrolysis degrees were obtained in 4 h for 1 % raw rice starch and 1 h for 8 % concentration, indicating a very rapid speed of hydrolysis. The presence of a starch residue resistant was the main limiting factor for complete hydrolysis, although end product inhibition also existed, especially at high starch concentrations. AmyP randomly attacks unique or susceptible sites on raw rice starch granules, and releases glucose, maltose, and maltotriose as end products. This is the first biochemical characterization of the raw starch-degrading ability of an α-amylase of family GH13_37. The specific ability towards raw rice starch has never been described before, and this makes AmyP a promising candidate for use as a novel enzyme in rice starch processing.




    Full Text Available This study investigated the possibility of dehydrating Isopropyl Alcohol – water mixture using oxidized starch from potato. The starch was modified using calcium hypochlorite. Central composite design was used to determine the effects of the four dehydrating variables; temperature, contact time, initial concentration of the isopropyl alcohol water solution and the adsorbent/solution ratio on the final concentration of the isopropyl alcohol water mixture. Based on the central composite design, a quadratic verses 2 factor interaction model was developed. The significant factors on the experimental design response were identified from the analysis of variance. The optimum conditions for the dehydration reaction were obtained by using temperature of 35oC, time of 40 minutes, adsorbent/solution ratio of 1:4 and initial concentration of 40% which resulted in finalconcentration of 43.968%.

  1. Calcium chloride effects on the glass transition of condensed systems of potato starch.

    Chuang, Lillian; Panyoyai, Naksit; Katopo, Lita; Shanks, Robert; Kasapis, Stefan


    The effect of calcium chloride on the structural properties of condensed potato starch undergoing a thermally induced glass transition has been studied using dynamic mechanical analysis and modulated differential scanning calorimetry. Extensive starch gelatinisation was obtained by hot pressing at 120°C for 7 min producing materials that covered a range of moisture contents from 3.7% w/w (11% relative humidity) to 18.8% w/w (75% relative humidity). FTIR, ESEM and WAXD were also performed in order to elucidate the manner by which salt addition affects the molecular interactions and morphology of condensed starch. Experimental protocol ensured the development of amorphous matrices that exhibited thermally reversible glassy consistency. Both moisture content and addition of calcium chloride affected the mechanical strength and glass transition temperature of polymeric systems. Highly reactive calcium ions form a direct interaction with starch to alter considerably its structural properties via an anti-plasticizing effect, as compared to the polymer-water matrix.

  2. High phosphorylase activity is correlated with increased potato minituber formation and starch content during extended clinorotation

    Nedukha, O. M.; Schnyukova, E. I.; Leach, J. E.


    The major purpose of these experiments were to investigate growth of potato storage organs and starch synthesis in minitubers at slow horizontal clinorotation (2 rpm), which partly mimics microgravity, and a secondary goal was to study the activity and localization of phosphorylase (EC in storage parenchyma under these conditions. Miniplants of Solanum tuberosum L. (cv Adreta) were grown in culture for 30 days for both the vertical control and the horizontal clinorotation. During long-term clinorotation, an acceleration of minituber formation, and an increase of amyloplast number and size in storage parenchyma cells, as well as increased starch content, was observed in the minitubers. The differences among cytochemical reaction intensity, activity of phosphorylase, and carbohydrate content in storage parenchyma cells of minitubers grown in a horizontal clinostat were established by electron-cytochemical and biochemical methods. It is shown that high phosphorylase activity is correlated with increased starch content during extended clinorotation. The results demonstrate the increase in carbohydrate metabolism and possible accelerated growth of storage organs under the influence of microgravity, as mimicked by clinorotation; therefore, clinorotation can be used as a basis for future studies on mechanisms of starch synthesis under microgravity.

  3. SEM studies of the structure of the gels prepared from untreated and radiation modified potato starch

    Cieśla, Krystyna; Sartowska, Bożena; Królak, Edward


    Potato starch was irradiated with a 60Co gamma rays using doses of 5, 10, 20 and 30 kGy. Gels containing ca. 9.1% of starch were prepared by heating the starch suspensions in the heating chamber stabilized at 100 °C. Four procedures were applied for preparation of the samples in regard to SEM studies and the ability to observe the radiation effect by SEM was assessed for each method. Differences were observed between the SEM images recorded for the non-irradiated samples prepared using all the methods, and those irradiated. Images of the non-irradiated gels indicate generally a honey-comb structure, while smooth areas but with oriented fractures has appeared after irradiation. Modification of gel structure corresponds to the applied dose. The results were related to the process of gel formation (as observed by means of the hot stage microscope) to decrease in swelling power of the irradiated starch and to decreased viscosity of the resulting gels. It can be concluded that the differences in structural properties of gels shown by SEM result probably due to the better homogenization of the gels formed after radiation induced degradation.

  4. Characterization of films made with chayote tuber and potato starches blending with cellulose nanoparticles.

    Aila-Suárez, Selene; Palma-Rodríguez, Heidi M; Rodríguez-Hernández, Adriana I; Hernández-Uribe, Juan P; Bello-Pérez, Luis A; Vargas-Torres, Apolonio


    The aim of this study was to characterize chayotextle starch films reinforced with cellulose (C) and cellulose nanoparticle (CN) (at concentrations of 0.3%, 0.5%, 0.8% and 1.2%), using thermal, mechanical, physicochemical, permeability, and water solubility tests. C was acid-treated to obtain CN. The films were prepared by casting; potato starch and C were used as the control. The solubility of the starch films decreased with the addition of C and CN compared with its respective film without C and CN. No statistical difference (α=0.05) was found in the films added with different concentrations of C and CN. In general, the mechanical properties were improved with the addition of C and CN, and higher values of tensile strength and elastic modulus were determined in the films reinforced with CN. The melting temperature and enthalpy increased with the addition of C and CN, and the values of both thermal parameters were higher in the films with CN than with C; the enthalpy value of the film decreased when the concentration of C or CN increased in the composite. Low concentration of C and CN is better distributed in the matrix film. The addition of C and CN in the starch films improved some mechanical, barrier, and functional properties.

  5. Expression of an (Engineered) 4,6-α-Glucanotransferase in Potato Results in Changes in Starch Characteristics

    Xu, Xuan; Dechesne, Annemarie; Visser, Richard G. F.; Trindade, Luisa M.


    Starch structure strongly influences starch physicochemical properties, determining the end uses of starch in various applications. To produce starches with novel structure and exploit the mechanism of starch granule formation, an (engineered) 4, 6-α-glucanotransferase (GTFB) from Lactobacillus reuteri 121 was introduced into two potato genetic backgrounds: amylose-containing line Kardal and amylose-free mutant amf. The resulting starches showed severe changes in granule morphology regardless of genetic backgrounds. Modified starches from amf background exhibited a significant increase in granule size and starch phosphate content relative to the control, while starches from Kardal background displayed a higher digestibility, but did not show changes in granule size and phosphate content. Transcriptome analysis revealed the existence of a mechanism to restore the regular packing of double helices in starch granules, which possibly resulted in the removal of novel glucose chains potentially introduced by the (engineered) GTFB. This amendment mechanics would also explain the difficulties to detect alterations in starch fine structure in the transgenic lines. PMID:27911907

  6. BIHON TYPE NOODLES FROM HEAT MOISTURE TREATED STARCH OF FOUR VARIETIES OF SWEET POTATO [Mi Tipe Bihun dari Pati Heat Moisture Treatment dari Empat Varietas Ubi Jalar

    Vera Apryana Lase


    Full Text Available Sweet potato starch has limited uses in food industry, but modification of its properties may make it more suitable for use especially for starch based food such as bihon type noodle. The objective of this research was to study the effect of heat moisture treated starch from 4 varieties of sweet potato on the quality of its bihon type noodle. Four different varieties of sweet potato i.e. white, yellow, orange and purple tuber were treated with heat moisture treatment (HMT. The HMT was performed by exposing the starch to high temperature (110°C for 3 hours at a moisture content of 25%. The HMT modified sweet potato starch was then processed into bihon type noodle. As a control, a commercial bihon type noodle made from rice starch was used. Parameters evaluated were the modified starch and bihon properties. The results showed that the modification of starch with HMT could increase the peak viscosity, setback viscosity, final viscosity and gelatinization temperature but lower the value of the breakdown viscosity. The best bihon from the four varieties of sweet potatoes was that made from white sweet potato starch because it has low cooking losses, low fat, but has high color/brightness and is preferred by panelist.

  7. Effect of Tribomechanical Micronisation and Activation Treatment on Textural and Thermophysical Properties of Wheat and Potato Starch Gels

    Verica Batur


    Full Text Available The aim of this study is to determine various textural properties of heat-induced gels prepared from wheat and potato starch suspensions (10 % treated with tribomechanical micronisation and activation (TMA. Particle size measurements showed that the TMA treatment caused a significant decrease in particle size and change in particle size distribution of powdered starches. Scanning electron microphotographs showed an obvious impact on the structure and size of starch granules. The effect of TMA treatment on the texture profile of wheat and potato starch gels was assessed by measuring their textural properties, such as hardness, adhesiveness, cohesiveness, springiness and gumminess. The texture profile analyses of the TMA-treated wheat and potato starch gels showed lower hardness and gumminess; however, adhesiveness, cohesiveness and springiness were higher when compared with untreated suspensions. TMA treatment caused no significant lowering of the initial gelatinization temperatures. Results of differential scanning calorimetry measurements showed a decrease in the enthalpy of gelatinization. This can be explained by the disruption of starch granules by mechanical forces during the TMA treatment, which made the granules more permeable to water during the heating step of differential scanning calorimetry analysis.

  8. Starch poisoning

    Cooking starch poisoning; Laundry starch poisoning ... Cooking and laundry starch are both made from vegetable products, most commonly: Corn Potatoes Rice Wheat Both are usually considered nonpoisonous (nontoxic), but ...

  9. The Influence of Oligosaccharides on Properties of Sweet Potato Starch%低聚糖对红薯淀粉性质的影响

    李飞; 陈梦雪; 胡雅婕; 李光磊; 曾洁


    向红薯淀粉中添加不同种类及添加量的低聚糖,测定淀粉粘度、碘蓝值、凝沉性,以此来研究低聚糖对红薯淀粉性质的影响。结果表明:添加不同种类、不同量的低聚糖对红薯淀粉的粘度、碘蓝值、凝沉性有较大影响;麦芽糖对红薯淀粉的热稳定性和碘蓝值影响最大,低聚木糖对红薯淀粉的凝沉性影响最大。%To add oligosaccharides of different types and amount in sweet potato starch for determining starch viscosity, starch iodine blue value and retrogradation in order to study the influence of oligosaccharides on sweet potato starch properties. The result showed that adding different types and different amount oligosaccharides had big influence on starch viscosity, starch iodine blue value and retrogra-dation of sweet potato starch;maltose had the biggest influence on thermal stability and starch iodine blue value of sweet potato starch, xylo oligosaccharides had the biggest influence on retrogradation of sweet potato starch.

  10. Granular size of potato starch affects structural properties, octenylsuccinic anhydride modification and flowability.

    Wang, Chan; Tang, Chuan-He; Fu, Xiong; Huang, Qiang; Zhang, Bin


    Native potato starch (PS) granules were separated into three size fractions: larger than 30μm (P-L), 15-30μm (P-M), and smaller than 15μm (P-S). The morphological and crystalline structure of fractionated potato starches were investigated by light and scanning electron microscopy (SEM), X-ray diffraction (XRD) and differential scanning calorimetry (DSC). The P-L fraction showed ellipsoidal shape and B-type X-ray pattern, whereas the P-S fraction had spherical shape and A-type pattern. The fluorophore-assisted capillary electrophoresis data showed that the P-L fraction had more B2 chains and less short A and B1 chains than the P-S counterparts. Smaller granules with larger specific surface area had higher degree of substitution when reacted with octenylsuccinic anhydride (OSA), and showed more uniform distribution of octenylsuccinate substituents. Both OSA modified and unmodified P-S samples showed higher flowability compared with the P-L counterparts.

  11. Utilization of potato starch processing wastes to produce animal feed with high lysine content.

    Li, Ying; Liu, Bingnan; Song, Jinzhu; Jiang, Cheng; Yang, Qian


    This work aims to utilize wastes from the potato starch industry to produce single-cell protein (SCP) with high lysine content as animal feed. In this work, S-(2-aminoethyl)-L-cysteine hydrochloride-resistant Bacillus pumilus E1 was used to produce SCP with high lysine content, whereas Aspergillus niger was used to degrade cellulose biomass and Candida utilis was used to improve the smell and palatability of the feed. An orthogonal design was used to optimize the process of fermentation for maximal lysine content. The optimum fermentation conditions were as follows: temperature of 40°C, substrate concentration of 3%, and natural pH of about 7.0. For unsterilized potato starch wastes, the microbial communities in the fermentation process were determined by terminal restriction fragment length polymorphism analysis of bacterial 16S rRNA genes. Results showed that the dominant population was Bacillus sp. The protein quality as well as the amino acid profile of the final product was found to be significantly higher compared with the untreated waste product at day 0. Additionally, acute toxicity test showed that the SCP product was non-toxic, indicating that it can be used for commercial processing.

  12. Identification a Novel Raw-Starch-Degrading-α-Amylase from a Tropical Marine Bacterium

    Zeily Nurachman


    Full Text Available Problem statement: Bacteria from the surface of the tropical marine hard coral Acropora sp. were screened for producing raw-starch-degrading-á-amylase. Approach: Based on its 16s rDNA sequence, a bacterium that produced the highest amylolitic activity was identified as Bacillus amyloliquifaciens ABBD. The bacterial isolate secreted a á-amylase extracellularly and then the enzyme was partially purified by ammonium sulfate precipitation followed by anion exchange chromatography. Results: Electrophoresis results both SDS-PAGE and native PAGE suggested that the enzyme was a heterodimeric protein (97 kDa consisting of 45 and 55 kDa subunits. The á-amylase had an optimum pH of 7.0 and temperature of 60°C. More than 80% activity of the enzyme was retained under high salt conditions (up to 20% NaCl. The enzyme remained stable at 50°C for 1 h. Starch hydrolysis by the enzyme at 70°C yielded oligosaccharides (G2-G4 and at room temperature yielded glucose/maltose (G1 and G2. Conclusion: The B. amyloliquifaciens ABBD á-amylase was capable of degrading various raw starch granules from corn, rice, cassava and sago at room temperature.

  13. Effect of temperature-cycled retrogradation on in vitro digestibility and structural characteristics of waxy potato starch.

    Xie, Yao-Yu; Hu, Xiao-Pei; Jin, Zheng-Yu; Xu, Xue-Ming; Chen, Han-Qing


    The effects of temperature-cycled retrogradation treatment on the structural characteristics and in vitro digestibility of waxy potato starch were investigated in this study. The results showed that the maximum yield of slowly digestible starch (SDS) in waxy potato starch reached 38.63% by retrogradation treatment under temperature cycles of 4/25°C for 3 days with an interval of 24h. The starch products prepared under the temperature cycles of 4/25°C exhibited a narrower melting temperature range (Tc-To), a higher melting enthalpy (ΔH) and a higher IR absorbance ratio (1047cm(-1)/1022cm(-1)) than that prepared at a constant temperature of 25°C. Compared to native starch, X-ray diffraction pattern of treated starch was altered from B-type to C-type. Furthermore, the relative crystallinity of the starch products prepared under temperature-cycled retrogradation was the highest. This study suggests that more imperfect crystallites are formed in the crystalline matrix under temperature-cycled retrogradation, resulting in a high yield of SDS.

  14. Glucose 1-phosphate is efficiently taken up by potato (Solanum tuberosum) tuber parenchyma cells and converted to reserve starch granules.

    Fettke, Joerg; Albrecht, Tanja; Hejazi, Mahdi; Mahlow, Sebastian; Nakamura, Yasunori; Steup, Martin


    Reserve starch is an important plant product but the actual biosynthetic process is not yet fully understood. Potato (Solanum tuberosum) tuber discs from various transgenic plants were used to analyse the conversion of external sugars or sugar derivatives to starch. By using in vitro assays, a direct glucosyl transfer from glucose 1-phosphate to native starch granules as mediated by recombinant plastidial phosphorylase was analysed. Compared with labelled glucose, glucose 6-phosphate or sucrose, tuber discs converted externally supplied [(14)C]glucose 1-phosphate into starch at a much higher rate. Likewise, tuber discs from transgenic lines with a strongly reduced expression of cytosolic phosphoglucomutase, phosphorylase or transglucosidase converted glucose 1-phosphate to starch with the same or even an increased rate compared with the wild-type. Similar results were obtained with transgenic potato lines possessing a strongly reduced activity of both the cytosolic and the plastidial phosphoglucomutase. Starch labelling was, however, significantly diminished in transgenic lines, with a reduced concentration of the plastidial phosphorylase isozymes. Two distinct paths of reserve starch biosynthesis are proposed that explain, at a biochemical level, the phenotype of several transgenic plant lines.

  15. Large-scale isolation, fractionation, and purification of soluble starch-synthesizing enzymes: starch synthase and branching enzyme from potato tubers.

    Mukerjea, Rupendra; Falconer, Daniel J; Yoon, Seung-Heon; Robyt, John F


    Soluble starch-synthesizing enzymes, starch synthase (SSS) and starch-branching enzyme (SBE), were isolated, fractionated, and purified from white potato tubers (Solanum tuberosum) on a large scale. Five steps were used: potato tuber extract from 2 kg of peeled potatoes, two acetone precipitations, and two fractionations on a large ultrafiltration polysulfone hollow fiber 100 kDa cartridge. Three kinds of fractions were obtained: (1) mixtures of SSS and SBE; (2) SSS, free of SBE; and (3) SBE, free of SSS. Contaminating enzymes (amylase, phosphorylase, and disproportionating enzyme) and carbohydrates were absent from the 2nd acetone precipitate and from the column fractions, as judged by the Molisch test and starch triiodide test. Activity yields of 122% (300,000-400,000 units) of SSS fractions and 187% (40,000-50,000 units) of SBE fractions were routinely obtained from the cartridge. Addition of 0.04% (w/v) polyvinyl alcohol 50K and 1 mM dithiothreitol to the glycine buffer (pH 8.4) gave long-term stability and higher yields of SSS and SBE, due to activation of inactive enzymes. Several SSS and SBE fractions from the two fractionations had very high specific activities, indicating high degrees of purification. Polyacrylamide gel electrophoresis of selected SSS and SBE fractions gave two to five SSS and/or SBE activity bands, corresponding to the one to five protein bands present in the 2nd acetone precipitate.

  16. The effect of process conditions on the alpha-amylolytic hydrolysis of amylopectin potato starch : an experimental design approach

    Marchal, L.M.; Jonkers, J.; Franke, G.T.; Goooijer, de C.D.; Tramper, J.


    The hydrolysis of amylopectin potato starch with Bacillus licheniformis α-amylase (Maxamyl) was studied under industrially relevant conditions (i.e. high dry-weight concentrations). The following ranges of process conditions were chosen and investigated by means of an experimental design: pH [5.6-

  17. Identification of the thermal transitions in potato starch at a low water content as studied by preparative DSC

    Steeneken, P.A.M.; Woortman, A.J.J.


    The aim of this work was to identify the transitions in the complex DSC profiles of potato starch at a low water content. Preparative DSC involves the thermal processing of samples in stainless steel DSC pans in a way that allows their subsequent structural characterization. The low temperature (LT)




    Chimaeric genes of promoter sequences from the potato gene encoding granule-bound starch synthase (GBSS) and the beta-glucuronidase (GUS) reporter gene were used to study GBSS expression and regulation. Analysis of stable transformants revealed that a GBSS promoter sequence of 0.4 kb was sufficient

  19. Resistant starch analysis of commonly consumed potatoes: Content varies by cooking method and service temperature but not by variety

    Resistant starch (RS) has properties which may provide health benefits. We conducted a study to determine the contributions of cultivar, cooking method and service temperature on the RS contents of potatoes (Solanum tuberosum L.). We hypothesized that the RS content would vary by variety, cooking me...

  20. The effect of process conditions on the alpha-amylolytic hydrolysis of amylopectin potato starch : an experimental design approach

    Marchal, L.M.; Jonkers, J.; Franke, G.T.; Goooijer, de C.D.; Tramper, J.


    The hydrolysis of amylopectin potato starch with Bacillus licheniformis α-amylase (Maxamyl) was studied under industrially relevant conditions (i.e. high dry-weight concentrations). The following ranges of process conditions were chosen and investigated by means of an experimental design: pH [5.6- 7

  1. Effects of Agrobacterial rol-Genes on the Thermodynamic and Structural Features of Starches Extracted from Potato Microtubers

    Wasserman, L.A.; Aksenova, N.P.; Konstantinova, T.N.; Sergeeva, L.; Golyanovskaya, S.A.; Krivandin, A.V.; Romanov, G.A.


    Wild-type potato (Solanum tuberosum L.) plants and their transformants harboring agrobacterial rolB or rolC genes under control of the patatin class I promoter were cultured in vitro. These plants were used as a source of single-node stem cuttings. The structure of native starch in tubers formed on

  2. Identification of the thermal transitions in potato starch at a low water content as studied by preparative DSC

    Steeneken, P.A.M.; Woortman, A.J.J.


    The aim of this work was to identify the transitions in the complex DSC profiles of potato starch at a low water content. Preparative DSC involves the thermal processing of samples in stainless steel DSC pans in a way that allows their subsequent structural characterization. The low temperature

  3. Effect of genetic modification of potato starch on decomposition of leaves and tubers and on fungal decomposer communities

    Hannula, S.E.; De Boer, W.; Baldrian, P.; Van Veen, J.A.


    As part of a risk evaluation of growing genetically modified crops, we investigated the effects of a genetic modification of starch quality (increased level of amylopectin) in potato tubers (Solanum Tuberosum L.) on the decomposition of tissues (tubers and leaves) as well as on the associated fungal

  4. Bioethanol Production from Uncooked Raw Starch by Immobilized Surface-engineered Yeast Cells

    Chen, Jyh-Ping; Wu, Kuo-Wei; Fukuda, Hideki

    Surface-engineered yeast Saccharomyces cerevisiae codisplaying Rhizopus oryzae glucoamylase and Streptococcus bovis α-amylase on the cell surface was used for direct production of ethanol from uncooked raw starch. By using 50 g/L cells during batch fermentation, ethanol concentration could reach 53 g/L in 7 days. During repeated batch fermentation, the production of ethanol could be maintained for seven consecutive cycles. For cells immobilized in loofa sponge, the concentration of ethanol could reach 42 g/L in 3 days in a circulating packed-bed bioreactor. However, the production of ethanol stopped thereafter because of limited contact between cells and starch. The bioreactor could be operated for repeated batch production of ethanol, but ethanol concentration dropped to 55% of its initial value after five cycles because of a decrease in cell mass and cell viability in the bioreactor. Adding cells to the bioreactor could partially restore ethanol production to 75% of its initial value.

  5. Development of nanocomposites based on potato starch; Desenvolvimento de nanocompositos a base de amido de batata

    Brito, Luciana Macedo; Tavares, Maria Ines Bruno, E-mail: [Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ (Brazil). Instituto de Macromoleculas


    Nanocomposites of potato starch were prepared by the solution intercalation method with the addition of organically modified montmorillonite clay (Viscogel B and unmodified sodic clay (NT25) as well as modified and unmodified silica (R972 and A200, respectively), using water as the solvent. The nanocomposites were characterized by conventional techniques of X-ray diffraction and thermogravimetric analysis. They were also characterized using the non-conventional low-field nuclear magnetic resonance, which is an effective alternative technique for characterizing nanocomposites. This technique allows one to investigate dispersion of nanofillers by the degree of intercalation and/or exfoliation, in addition to determine the distribution of nanoparticles in the polymer matrix and modifications of the molecular mobility of these fillers. The nanostructured materials obtained with the clays presented good dispersion and formation of mixed nanomaterials, with different degrees of intercalation and exfoliation. The mobility of the material decreased upon adding silica in the starch matrix, which applied to both types of silica. From the TGA technique, a slight increase in thermal stability of the nanocomposite was noted in relation to the starch matrix. (author)

  6. Modification of potato starch granule structure and morphology in planta by expression of starch binding domain fusion proteins

    Huang, X.


    Producing starches with altered composition, structure and novel physico-chemical properties in planta by manipulating the enzymes which are involved in starch metabolism or (over)expressing heterologous enzymes has huge advantages such as broadening the range of starch applications and reducing the costs of the post-harvest starch modification. The starch binding domain (SBD) technology has been extensively explored in our lab for modifying starch in planta and producing so-called “tailored ...

  7. Effects of storage temperatures and annealing conditions on the structure and properties of potato (Solanum tuberosum) starch.

    Tester, R F; Ansell, R; Snape, C E; Yusuph, M


    Starches were extracted from freshly harvested potatoes (12 cultivars, grown in Perthshire) and the properties of the starches of six cultivars were compared with starches extracted from the same samples but stored at 5, 25 or 55 degrees C for 7 days before extraction. The amylose (total) content of the freshly extracted starches from tubers stored at 5, 25 or 55 degrees C was on average 27.9+/-2.3, 28.3+/-1.7, 29.2+/-2.2 and 28.8+/-1.5%, respectively, with corresponding phosphorus representing 60+/-16, 64+/-9, 61+/-5 and 63+/-9 mg 100 g(-1). The unit chain distribution by chromatography of the amylopectin molecules from the starches extracted from the different conditions was very similar with an average degree of polymerisation (DP) of 26+/-2 where the two major fractions (F1 and F2) represented 54+/-2 and 19+/-1, respectively. Peak gelatinisation temperatures (Tp) and enthalpies (DeltaH) for the freshly extracted starches and from tubers stored at 5 or 25 degrees C were very similar (63.3+/-1.5 degrees C and 18.6+/-0.8 J g(-1); 63.1+/-1.0 degrees C and 17.7+/-1.5 J g(-1) and; 62.9+/-0.7 degrees C and 18.7+/-1.1 J g(-1), respectively) although starches stored at 55 degrees C were annealed, where Tp represented 71.1+/-1.1 degrees C and DeltaH 18.1+/-1.4 J g(-1). These in situ-annealed starches were comparable in terms of gelatinisation characteristics to annealed freshly extracted starches where on average, T(p) represented 72.7+/-1.0 degrees C and DeltaH 20.8+/-1.0 J g(-1). Annealing of tubers in situ prior to processing might be beneficial with respect to developing new potato-based products.

  8. Effect of irradiation for recovery of organic wastes from potato starch wastewater with chitosan

    Kume, Tamikazu; Takehisa, Masaaki

    The irradiation effect on recovery of organic substances from potato starch wastewater with aid of chitosan and disinfection were investigated for recycling the organic wastes into animal feeds. Chitosan was effective as a coagulant for suspended solids in the wastewater and the optimum concentration was 8-10 x 10 -30/0. The irradiation promotes the coagulation of the organic wastes. Especially, the coagulation of the proteins with chitosan increased by irradiation since the soluble proteins became insoluble by irradiation. The numbers of total aerobic bacteria in the wastewater and in the coagulum with chitosan were 8.0 x 10 7 and 3.5 x 10 8counts/ ml, respectively, and decreased to 11 and 45 counts/ml by 1.0 Mrad irradiation.

  9. Comparative Study on Physicochemical Properties of Potato Starch and Mung Bean Starch%土豆淀粉和绿豆淀粉理化性质的比较研究

    侯蕾; 韩小贤; 郑学玲; 刘翀; 逯蕾


    Mung bean starch and potato starch are used widely in industrial production. This paper compares the Physical-chemical properties of these two kinds of starch , including the polarization cross ,the granular size distribution,the transparency,the drainage rate,the solidification sedimentation capacity, the solubility and swelling power, the pasting properties. The result showed that the polarization cross of mung bean starch and potato starch are both obvious. The average grain diameter of potato starch is bigger than mung bean starch. Mung bean starch is the easier to retrograde than potato starch , its transparency is lower than potato starch and it has a better ability in gel forming than the other one. The freeze-thawing stability of potato starch is bad. The potato starch is easier soluble in water than mung bean starch. Mung bean starch is better in viscosity thermal stability than potato starch.%土豆淀粉和绿豆淀粉在工业生产中应用较为广泛,本文对这两种淀粉进行了基本理化性质的比较,包括:偏光十字、淀粉粒度分布、透明度、冻融稳定性、凝沉性、溶解度和膨润力、淀粉糊化特性。结果表明:土豆淀粉和绿豆淀粉的偏光十字都很明显;土豆淀粉的平均粒径大于绿豆淀粉;土豆淀粉不容易回生,其透明度高于绿豆淀粉,凝胶能力较弱;土豆淀粉冻融稳定性较弱,其不适合运用于冷冻食品;土豆淀粉比绿豆淀粉易溶于水;绿豆淀粉的热稳定性优于土豆淀粉。

  10. Non-contact AFM investigation of influence of freezing process on the surface structure of potato starch granule

    Krok, F.; Szymońska, J.; Tomasik, P.; Szymoński, M.


    To assess the influence of the freezing process on the surface structure of a potato starch granule, a non-contact Atomic Force Microscopy (NC-AFM) investigation at ambient conditions has been undertaken. The observations were carried out for dried (oven-dried) and native (air-dried) starch. The obtained AFM images of the native starch granule surface demonstrated it as not uniformly smooth and having rough undulating appearance with layers of adsorbed water which could be removed by oven drying in 130°C. After freezing, the dried starch granule surface still consisted of nodules of about 100 nm in diameter. Significant changes in the granule surface appearance can be seen for dried starch samples frozen with some excess of water as well as for native starch samples frozen with its original water. Then the aggregation and polishing of the granules was observed and their surface revealed a microstructure with distinct ring-like protrusions of about 300 nm in diameter. Our observations tally with the amylopectine "blocket" starch granule structure model proposed in the literature and allowed to conclude that freezing may be a useful tool, among other methods, for modifying starch granule properties.

  11. Development of a pilot system for converting sweet potato starch into glucose syrup

    Silayo, Valerian C K.; Lu, John Y.; Aglan, Heshmat A.; Bovell-Benjamin, A. C. (Principal Investigator)


    Sweet potato has been chosen as one of NASA's crops to support human beings in future space missions. One of the possible uses is to make syrup that can be used as a general sweetener. In this work a simple engineering system for converting sweet potato starch into glucose syrup was studied on a laboratory scale. The system comprises the following main units: a blender, continuous stirred tank reactor (CSTR), centrifugal and vacuum filters, deionization column and vacuum evaporator. The system was tested by carrying out conversion processes from fresh sweet potato roots. The roots were pealed, sliced, homogenized, heated and hydrolyzed by diastase of malt and Dextrozyme C (Novo Nordisk BioChem, North America, Inc.) enzymes in the CSTR. After hydrolysis the slurry was filtered, de-ionized and concentrated to get glucose syrup. The performance of the system was evaluated based on the quality of the conversion. The main factor was the level of reducing sugars except for the deionization where ash content and color were the main factors. Through careful control of the system units, good heating performance in the CSTR was obtained and the hydrolysis process attained sufficient conversion. The filtration process that incorporated the centrifuge was faster than when it was by-passed to the vacuum filter but losses in sugars were higher. Deionization removed more than 90% of the ash and reduced pigmentation, with probable insignificant losses in sugars during the deionization process. Recovery levels when the centrifuge was used and when it was by-passed could reach about 65% and 78%, respectively. These correspond to reducing sugar concentration of 259 and 310 mg/ml in 150-ml syrups from 300 g of sweet potatoes in each process. However, from concentration trials, syrups with volumes of 100 and 70 ml with the respective dextrose equivalence of 281 and 213 mg/ml were obtained. The syrups obtained were brownish in color and the process that employed centrifugal filtration

  12. Enhanced production of raw starch degrading enzyme using agro-industrial waste mixtures by thermotolerant Rhizopus microsporus for raw cassava chip saccharification in ethanol production.

    Trakarnpaiboon, Srisakul; Srisuk, Nantana; Piyachomkwan, Kuakoon; Sakai, Kenji; Kitpreechavanich, Vichien


    In the present study, solid-state fermentation for the production of raw starch degrading enzyme was investigated by thermotolerant Rhizopus microsporus TISTR 3531 using a combination of agro-industrial wastes as substrates. The obtained crude enzyme was applied for hydrolysis of raw cassava starch and chips at low temperature and subjected to nonsterile ethanol production using raw cassava chips. The agro-industrial waste ratio was optimized using a simplex axial mixture design. The results showed that the substrate mixture consisting of rice bran:corncob:cassava bagasse at 8 g:10 g:2 g yielded the highest enzyme production of 201.6 U/g dry solid. The optimized condition for solid-state fermentation was found as 65% initial moisture content, 35°C, initial pH of 6.0, and 5 × 10(6) spores/mL inoculum, which gave the highest enzyme activity of 389.5 U/g dry solid. The enzyme showed high efficiency on saccharification of raw cassava starch and chips with synergistic activities of commercial α-amylase at 50°C, which promotes low-temperature bioethanol production. A high ethanol concentration of 102.2 g/L with 78% fermentation efficiency was achieved from modified simultaneous saccharification and fermentation using cofermentation of the enzymatic hydrolysate of 300 g raw cassava chips/L with cane molasses.

  13. Influence of incorporated wild Solanum genomes on potato properties in terms of starch nanostructure and glycoalkaloid content.

    Väänänen, Tiina; Ikonen, Teemu; Rokka, Veli-Matti; Kuronen, Pirjo; Serimaa, Ritva; Ollilainen, Velimatti


    Interspecific somatic hybrids produced by protoplast fusion between two wild Solanum species (S. acaule, acl; S. brevidens, brd) and cultivated potato Solanum tuberosum (tbr) were analyzed in terms of the starch nanometer-range structure and glycoalkaloid (GA) contents. The crystallinity of starch granules, the average size of starch crystallites, and the lamellar distances were obtained from tuber samples using wide-angle and small-angle X-ray scattering methods. These measurements showed that incorporation of wild genomes from either nontuberous (brd) or tuberous (acl) Solanum species caused no significant modifications of the nanostructure of potato starch. In contrast, the GA profiles of the hybrids, which were analyzed by LC-ESI-MS in both tuber and foliage samples, differed considerably from those of cultivated potato. Regardless of the low total tuber GA concentrations (approximately 9 mg/100 g of fresh weight), the somatic hybrids contained GAs not detected in the parental species. A high proportion of spirotype GAs consisting of 5,6-dihydrogenated aglycons, for example, alpha-tomatine and tomatidine bound with solatriose, and chacotriose were found in the hybrids. In conclusion, the foliage of interspecific hybrids contained a higher variation in the structures of GAs than did the tubers.

  14. Purification and properties of a novel raw starch degrading-cyclodextrin glycosyltransferase from Klebsiella pneumoniae AS- 22.

    Gawande, B N.; Patkar, A Y.


    A novel raw starch degrading alpha-cyclodextrin glycosyltransferase (CGTase; E.C., produced by Klebsiella pneumoniae AS-22, was purified to homogeneity by ultrafiltration, affinity and gel filtration chromatography. The specific cyclization activity of the pure enzyme preparation was 523 U/mg of protein. No hydrolysis activity was detected when soluble starch was used as the substrate. The molecular weight of the pure protein was estimated to be 75 kDa with SDS-PAGE and gel filtration. The isoelectric point of the pure enzyme was 7.3. The enzyme was most active in the pH range 5.5-9.0 whereas it was most stable in the pH range 6-9. The CGTase was most active in the temperature range 35-50 degrees C. This CGTase is inherently temperature labile and rapidly loses activity above 30 degrees C. However, presence of soluble starch and calcium chloride improved the temperature stability of the enzyme up to 40 degrees C. In presence of 30% (v/v) glycerol, this enzyme was almost 100% stable at 30 degrees C for a month. The K(m) and k(cat) values for the pure enzyme were 1.35 mg ml(-1) and 249 &mgr;M mg(-1) min(-1), respectively, with soluble starch as the substrate. The enzyme predominantly produced alpha-cyclodextrin without addition of any complexing agents. The conditions employed for maximum alpha-cyclodextrin production were 100 g l(-1) gelatinized soluble starch or 125 g l(-1) raw wheat starch at an enzyme concentration of 10 U g(-1) of starch. The alpha:beta:gamma-cyclodextrins were produced in the ratios of 81:12:7 and 89:9:2 from gelatinized soluble starch and raw wheat starch, respectively.

  15. Comparison of pasting and gel stabilities of waxy and normal starches from potato, maize, and rice with those of a novel waxy cassava starch under thermal, chemical, and mechanical stress.

    Sánchez, Teresa; Dufour, Dominique; Moreno, Isabel Ximena; Ceballos, Hernán


    Functional properties of normal and waxy starches from maize, rice, potato, and cassava as well as the modified waxy maize starch COLFLO 67 were compared. The main objective of this study is to position the recently discovered spontaneous mutation for amylose-free cassava starch in relation to the other starches with well-known characteristics. Paste clarity, wavelength of maximum absorption (lambda(max)), pasting properties, swelling power, solubility, and dispersed volume fraction measurements and gel stability (acid and alkaline resistance, shear, refrigeration, and freeze/thaw stability) were evaluated in the different types and sources of starch included in this study. lambda(max) in the waxy cassava starch was reduced considerably in comparison with that of normal cassava starch (535 vs 592 nm). RVA peak viscosity of waxy cassava starch was larger than in normal cassava starch (1119 vs 937 cP) and assumed a position intermediate between the waxy potato and maize starches. Acid, alkaline, and shear stability of waxy cassava starch were similar to normal cassava except for alkaline pH, at which it showed a low effect. Gels from normal root and tuber starches after refrigeration and freeze/thaw had lower syneresis than cereal starches. Gels from waxy starches (except for potato) did not present any syneresis after 5 weeks of storage at 4 degrees C. Waxy cassava starch was the only one not showing any syneresis after 5 weeks of storage at -20 degrees C. Natural waxy cassava starch is, therefore, a promising ingredient to formulate refrigerated or frozen food.

  16. Reduction of the plastidial phosphorylase in potato (Solanum tuberosum L.) reveals impact on storage starch structure during growth at low temperature.

    Orawetz, Tom; Malinova, Irina; Orzechowski, Slawomir; Fettke, Joerg


    Tubers of potato (Solanum tuberosum L.), one of the most important crops, are a prominent example for an efficient production of storage starch. Nevertheless, the synthesis of this storage starch is not completely understood. The plastidial phosphorylase (Pho1; EC catalyzes the reversible transfer of glucosyl residues from glucose-1-phosphate to the non-reducing end of α-glucans with the release of orthophosphate. Thus, the enzyme is in principle able to act during starch synthesis. However, so far under normal growth conditions no alterations in tuber starch metabolism were observed. Based on analyses of other species and also from in vitro experiments with potato tuber slices it was supposed, that Pho1 has a stronger impact on starch metabolism, when plants grow under low temperature conditions. Therefore, we analyzed the starch content, granule size, as well as the internal structure of starch granules isolated from potato plants grown under low temperatures. Besides wild type, transgenic potato plants with a strong reduction in the Pho1 activity were analyzed. No significant alterations in starch content and granule size were detected. In contrast, when plants were cultivated at low temperatures the chain length distributions of the starch granules were altered. Thus, the granules contained more short glucan chains. That was not observed in the transgenic plants, revealing that Pho1 in wild type is involved in the formation of the short glucan chains, at least at low temperatures.

  17. Overcoming hydrolysis of raw corn starch under industrial conditions with Bacillus licheniformis ATCC 9945a α-amylase.

    Šokarda Slavić, Marinela; Pešić, Milja; Vujčić, Zoran; Božić, Nataša


    α-Amylase from Bacillus licheniformis ATCC 9945a (BliAmy) was proven to be very efficient in hydrolysis of granular starch below the temperature of gelatinization. By applying two-stage feeding strategy to achieve high-cell-density cultivation of Escherichia coli and extracellular production of BliAmy, total of 250.5 U/mL (i.e. 0.7 g/L) of enzyme was obtained. Thermostability of amylase was exploited to simplify purification. The hydrolysis of concentrated raw starch was optimized using response surface methodology. Regardless of raw starch concentration tested (20, 25, 30 %), BliAmy was very effective, achieving the final hydrolysis degree of 91 % for the hydrolysis of 30 % starch suspension after 24 h. The major A-type crystalline structure and amorphous domains of the starch granule were degraded at the same rates, while amylose-lipid complexes were not degraded. BliAmy presents interesting performances on highly concentrated solid starch and could be of value for starch-consuming industries while response surface methodology (RSM) could be efficiently applied for the optimization of the hydrolysis.

  18. Characterization and Expression Analysis of Starch Branching Enzymes in Sweet Potato

    QIN Hua; ZHOU Shuang; ZHANG Yi-zheng


    Spatial and temporal expression patterns of Sbe1 and Sbe2 that encode starch branching enzyme (SBE) I and II, respectively, in sweet potato (Ipomoea batatas L.) were analyzed. Expression of both genes in Escherichia coli indicate that both genes encoded active SBE. Analysis with real-time quantitative polymerase chain reaction technique indicates that IbSbe1 mRNA was expressed at very low levels in leaves but was the predominant isoform in tuberous root while the reverse case was found for IbSbe2. The expression pattern of IbSbe1, closely resembles that of AGPase S, a gene coding for one of the subunits of ADP-glucose pyrophosphorylase, which is the key regulatory enzyme in the starch biosynthetic pathway. Western analysis detected at least two isoforms of SBE I in tuberous roots, those two isoforms showed adverse expression patterns with the development of the tuberous roots. Expression of the two IbSbe genes exhibited a diurnal rhythm during a 12-h cycle when fed a continuous solution of sucrose. Abscisic acid (ABA) was aother potent inducer of IbSbe expression, but bypassed the semidian oscillator.

  19. Production of bioethanol and associated by-products from potato starch residue stream by Saccharomyces cerevisiae

    Hashem, Mohamed [King Khalid University, Faculty of Science, Biological Science Department, P.O. Box 10255, Abha 61321 (Saudi Arabia); Darwish, Soumia M.I. [Department of Food Science and Technology, Faculty of Agriculture, Assiut University (Egypt)


    Potato starch residue stream produced during chips manufacturing was used as an economical source for biomass and bioethanol production by Saccharomyces cerevisiae. Results demonstrated that 1% H{sub 2}SO{sub 4} at 100 C for 1 h was enough to hydrolyze all starch contained in the residue stream. Two strains of S. cerevisiae (y-1646 and commercial one) were able to utilize and ferment the acid-treated residue stream under both aerobic and semi-anaerobic conditions. The maximum yield of ethanol (5.52 g L{sup -1}) was achieved at 35 C by S. cerevisiae y-1646 after 36 h when ZnCl{sub 2} (0.4 g L{sup -1}) was added. Addition of NH{sub 4}NO{sub 3} as a source of nitrogen did not significantly affect either growth or ethanol production by S. cerevisiae y-1646. Some secondary by-products including alcohol derivatives and medical active compound were found to be associated with the ethanol production process. (author)

  20. Study of heat-moisture treatment of potato starch granules by chemical surface gelatinization.

    Bartz, Josiane; da Rosa Zavareze, Elessandra; Dias, Alvaro Renato Guerra


    Native potato starch was subjected to heat-moisture treatment (HMT) at 12%, 15%, 18%, 21%, and 24% of moisture content at 110 °C for 1 h, and the effects on morphology, structure, and thermal and physicochemical properties were investigated. To reveal the internal structure, 30% and 50% of the granular surface were removed by chemical surface gelatinization in concentrated LiCl solution. At moisture contents of 12% and 15%, HTM reduced the gelatinization temperatures and relative crystallinity of the starches, while at moisture contents of 21% and 24 % both increased. The alterations on morphology, X-ray pattern, physicochemical properties, and increase of amylose content were more intense with the increase of moisture content of HMT. The removal of granular layers showed that the changes promoted by HMT occur throughout the whole granule and were pronounced at the core or peripheral region, depending of the moisture content applied during HMT. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  1. Sweet potato leaf extract inhibits the simulated in vitro gastrointestinal digestion of native starch

    Toong Long Jeng


    Full Text Available Several studies have reported the therapeutic use of caffeoylquinic acid (CQA derivatives in the management of hyperglycemia. This study used a simulated in vitro gastrointestinal digestion model to assess the inhibitory effects of CQA derivatives-rich sweet potato leaf extract (SPLE and a commercially produced green coffee bean extract (GCBE, each with total polyphenols contents of 452 mg g−1 and 278 mg g−1, respectively, against starch digestion. The changes in the amounts of total polyphenols and total CQA derivatives during in vitro gastrointestinal digestion were also examined. The results indicated that both extracts contained substantial levels of CQA derivatives (136 mg g−1 and 83.5 mg g−1 of extract for SPLE and GCBE, respectively. The amounts of total polyphenols and total CQA derivatives in 20 mg of SPLE and GCBE samples decreased from 9.04 mg to 0.58 mg and from 5.56 mg to 0.58 mg, and from 2.72 mg to 0.16 mg and from 1.67 mg to 0.10 mg, respectively, following in vitro gastrointestinal digestion and subsequent dialysis. When SPLE and GCBE were accompanied with starch for in vitro digestion test, they both exhibited inhibitory effect against starch digestion during simulated intestinal digestion, with estimated half maximal inhibitory concentration (IC50 values of 4.91 mg and 6.06 mg polyphenols, respectively. The amount of glucose permeated through dialysis membrane also decreased significantly in comparison with the extract-negative control. Thus, both SPLE and GCBE were capable of modulating the release of glucose from starch digestion in simulated intestinal tract. The observed inhibitory effects against glucose release were presumably due in part to the presence of CQA derivatives in the tested extracts. The SPLE had higher inhibitory effect against in vitro starch digestion than the commercially prepared reference GCBE. Therefore, the SPLE might be used to manage hyperglycemia over the long term.

  2. Thixotropic properties of waxy potato starch depending on the degree of the granules pasting.

    Krystyjan, Magdalena; Sikora, Marek; Adamczyk, Greta; Dobosz, Anna; Tomasik, Piotr; Berski, Wiktor; Łukasiewicz, Marcin; Izak, Piotr


    This paper presents the rheological instability (thixotropy/antithixotropy) of waxy potato starch (WPS) pastes depending on their concentration (1-5% w/w) and pasting temperature (80, 95 and autoclaved: 121°C, at 0.1MPa). The hysteresis loop, apparent viscosity at constant shear rate as well as the in-shear structural recovery tests with and without pre-shearing were applied. The pastes were also characterized by the granularity profile, molecular weight, polydispersity and optical transmittance. Differences in rheological properties of the pastes prepared at 80 and 95°C as well as autoclaved resulted from degree of granules pasting. At 121 °C dissolution of the granules occurred, while at the lower temperatures only the partial pasting of the granules took place. Pasting temperature of WPS significantly influenced rheological parameters of the resulted pastes which had thixotropic, antithixotropic or mixed thixotropic/antithixotropic behavior. Autoclaved pastes, regardless their concentration were antithixotropic as demonstrated by the areas of hysteresis loops derived from the flow curves signalized by the degree of structure recovery (DSR) which exceeded unity. The apparent viscosity of WPS pasted at 121°C strongly decreased as compared to the samples pasted at lower temperatures. Samples pasted at 80 and 95°C showed both thixotropic and antithixotropic behavior, with a predominance of the latter. The starch concentration played an important role in the formation of the rheological properties of the resulted pastes. Its influence was strongly connected with the degree of the granules pasting, therefore with the temperature of pastes preparation. For the pastes prepared at 80 and 95°C the values of thixotropy and apparent viscosity increased, while the values of DSR decreased with an increase of concentration. In the autoclaved pastes the antithixotropy, DSR and apparent viscosity increased with increasing starch concentration. It was also found that apart

  3. Production of ethanol directly from potato starch by mixed culture of Saccharomyces cerevisiae and Aspergillus niger using electrochemical bioreactor.

    Jeon, Bo Young; Kim, Dae Hee; Na, Byung Kwan; Ahn, Dae Hee; Park, Doo Hyun


    When cultivated aerobically, Aspergillus niger hyphae produced extracellular glucoamylase, which catalyzes the saccharification of unliquified potato starch into glucose, but not when grown under anaerobic conditions. The Km and Vmax of the extracellular glucoamylase were 652.3 mg starch l-1 and 253.3 mg glucose l-1 min-1, respectively. In mixed culture of A. niger and Saccharomyces cerevisiae, oxygen had a negative influence on the alcohol fermentation of yeast, but activated fungal growth. Therefore, oxygen is a critical factor for ethanol production in the mixed culture, and its generation through electrolysis of water in an electrochemical bioreactor needs to be optimized for ethanol production from starch by coculture of fungal hyphae and yeast cells. By applying pulsed electric fields (PEF) into the electrochemical bioreactor, ethanol production from starch improved significantly: Ethanol produced from 50 g potato starch l-1 by a mixed culture of A. niger and S. cerevisiae was about 5 g l-1 in a conventional bioreactor, but was 9 g l-1 in 5 volts of PEF and about 19 g l-1 in 4 volts of PEF for 5 days.

  4. In vitro digestibility and glycemic response of potato starch is related to granule size and degree of gelatinization.

    Parada, Javier; Aguilera, José M


    Starch granule microstructure affects the digestion of starch and its nutritional impact; however, the exact relationship between both factors is not clear. This study reports quantitative relationships between granule size (length and polygonal area), degree of gelatinization (DG), in vitro digestibility (by enzymatic methods), and glycemic response of potato starch granules gelatinized to various extents by heating at several constant temperatures in the range of 55 to 65 degrees C. DG measured by differential scanning calorimetry was closely related with heating temperature (R(2)= 0.997), size parameters of granules (measured by image analysis), in vitro digestion, and in vivo glycemic response (R(2) of adjusted models > 0.9); shape parameters of granules (measured by image analysis) were not related with DG. Results demonstrate that DG of starch strongly affects its digestibility in vitro, and may influence the postpandrial glycemic response. Future studies should be performed to investigate the effect of potato starch gelatinization on the nutritional impact at other temperatures and in more complex matrices.

  5. Hydration properties and phosphorous speciation in native, gelatinized and enzymatically modified potato starch analyzed by solid-state MAS NMR

    Larsen, Flemming H.; Kasprzak, Miroslaw Marek; Lærke, Helle Nygaard


    Hydration of granular, gelatinized and molecularly modified states of potato starch in terms of molecular mobility were analyzed by 13C and 31P solid-state MAS NMR. Gelatinization (GEL) tremendously reduced the immobile fraction compared to native (NA) starch granules. This effect was enhanced...... by enzyme-assisted catalytic branching with branching enzyme (BE) or combined BE and β-amylase (BB) catalyzed exo-hydrolysis. Carbons of the glycosidic α-1,6 linkages required high hydration rates before adopting uniform chemical shifts indicating solid-state disorder and poor water accessibility...

  6. Process Optimization for Synthesis of Octenyl Succinic Anhydride Modified Oxidized Sweet Potato Starch by Response Surface Analysis%响应面法优化氧化辛烯基琥珀酸甘薯淀粉酯的制备工艺

    刘强; 邬应龙; 何靖柳


    以氧化甘薯淀粉(oxidation sweet potato starch,OSPS)为原料,制备氧化辛烯基琥珀酸甘薯淀粉酯(octenylsuccinate anhydride-oxidation sweet potato starch,OSA-OSPS)。运用响应面分析(response surface method analysis,RSA)辛烯基琥珀酸酐(octenyl succinate anhydride,OSA)添加量、pH值、温度和时间对OSA-OSPS取代度(degreeof substitution,DS)的影响,得出最佳制备工艺:酸酐添加量7%、pH8.40、温度40℃,反应时间10h。采用快速黏度分析仪(rapid viscosity analyzer,RVA)分析表明:氧化甘薯淀粉峰值黏度较低,而经过OSA酯化后,峰值黏度又会有一定程度的提高,且随DS的增加呈上升趋势。%Oxidized sweet potato starch was used as the raw material to prepare octenyl succinic anhydride(OSA) modified oxidized sweet potato starch.The effects of OSA amount,pH,temperature and reaction time on degree of substitution(DS) of OSA-modified oxidized sweet potato starch were studied employing response surface analysis.The optimum process conditions determined were as follows: OSA amount 7%,pH 8.40,temperature 40 ℃,and reaction time 10 h.Rapid viscosity analyzer(RVA) analysis showed that the peak viscosity of sweet potato starch decreased after oxidation,and increased after furthermodification with OSA with a positive correlation with DS.

  7. Adaptation of the rumen microbial population to native potato starch degradation determined with the gas production technique and the nylon bag technique

    Cone, J.W.; Gelder, van A.H.


    Experiments were conducted to investigate the influence of the adaptation of rumen micro-organisms on the degradation of native potato starch (PS) in the rumen. Cows were fed with rations used for gas production (GP) analysis (dry cows, 1.6% starch) and for the nylon bag (NB) technique (lactating co


    van der Leij, Feike R.; VISSER, RGF; Ponstein, Anne S.; Jacobsen, Evert; Feenstra, Willem


    The genomic sequence of the potato gene for starch granule-bound starch synthase (GBSS; "waxy protein") has been determined for the wild-type allele of a monoploid genotype from which an amylose-free (amf) mutant was derived, and for the mutant part of the amf allele. Comparison of the wild-type seq

  9. Fermentation by amylolytic lactic acid bacteria and consequences for starch digestibility of plantain, breadfruit, and sweet potato flours

    Haydersah, J.; Chevallier, I.; Rochette, Isabelle; Mouquet Rivier, Claire; Picq, Christian; Marianne Pépin, T.; Icard-Vernière, Christèle; Guyot, Jean-Pierre


    The potential of tropical starchy plants such as plantain (Musa paradisiaca), breadfruit (Artocarpus communis), and sweet potato (Ipomoea batatas) for the development of new fermented foods was investigated by exploiting the capacity of some lactic acid bacteria to hydrolyze starch. The amylolytic lactic acid bacteria (ALAB) Lactobacillus plantarum A6 and Lactobacillus fermentum Ogi E1 were able to change the consistency of thick sticky gelatinized slurries of these starchy fruits and tubers ...

  10. Repeated batch fermentation from raw starch using a maltose transporter and amylase expressing diploid yeast strain.

    Yamakawa, Syun-ichi; Yamada, Ryosuke; Tanaka, Tsutomu; Ogino, Chiaki; Kondo, Akihiko


    We successfully demonstrated batch ethanol fermentation repeated ten times from raw starch with high ethanol productivity. We constructed a yeast diploid strain coexpressing the maltose transporter AGT1, alpha-amylase, and glucoamylase. The introduction of AGT1 allows maltose and maltotriose fermentation as well as the improvement of amylase activities. We also found that alpha-amylase activity during fermentation was retained by the addition of 10 mM calcium ion and that the highest alpha-amylase activity was 9.26 U/ml during repeated fermentation. The highest ethanol productivity was 2.22 g/l/h at the fourth batch, and after ten cycles, ethanol productivity of more than 1.43 g/l/h was retained, as was alpha-amylase activity at 6.43 U/ml.

  11. Modification of potato starch granule structure and morphology in planta by expression of starch binding domain fusion proteins

    Huang, X.


    Producing starches with altered composition, structure and novel physico-chemical properties in planta by manipulating the enzymes which are involved in starch metabolism or (over)expressing heterologous enzymes has huge advantages such as broadening the range of starch applications and reducing the

  12. 复合酶法制备马铃薯微孔淀粉的工艺研究%Study on Process Conditions of Preparation of Microporous Potatoes Starch with Complex Enzyme Method

    杨圣岽; 李兵; 张琳; 李欣欣; 张凌; 曲波; 王茜; 王丽华


    [ Objective ] The effects of using α-amylase and glucoamylase to prepare microporous potato starch were studied. [ Method ] Taking potato starch as raw materials, starch hydrolysis rate and the oil absorption as a measure of index, the influences of the reaction temperature, two enzymes proportion, the quantity of enzyme, the chroma of substrate, buffer solution pH and reaction time on microporous potato starch were investigated. [ Result ] The experimental results showed that the best technological conditions were reaction temperature 45 ℃ , enzyme ratio (glucoamylase /a-amylase) 6, the quantity of enzyme 1.0% , the substrate quantity chroma 0.14 g/ml, buffer solution pH 4, the reaction time 8 h. In such process condition, the oil adsorption rate of hydrolyzed potato starch was as high as 70.2% , starch hydrolytic ratio was 34. 16%. [ Conclusion ] The study provided a basis for the development and utilization of microporous starch.%[目的]研究糖化酶与α-淀粉酶制备马铃薯微孔淀粉的工艺.[方法]以马铃薯淀粉为原料,淀粉水解率和油脂吸附率为评价指标,考察反应温度、酶配比[糖化酶∶α-淀粉酶(W/W)]、加酶量、底物量浓度[淀粉∶溶液(W/V)]、缓冲液pH和反应时间6个因素对马铃薯淀粉微孔化的影响.[结果]马铃薯微孔淀粉的最佳制备工艺条件为反应温度45℃,酶配比6∶1,加酶量1.0%,底物量浓度0.14g/ml,缓冲液pH4,反应时间8h;在该条件下制得的微孔淀粉的油脂吸附率为70.2%,淀粉水解率为34.16%.[结论]该研究为微孔淀粉的开发和利用提供了依据.

  13. Starch Origin and Thermal Processing Affect Starch Digestion in a Minipig Model of Pancreatic Exocrine Insufficiency

    Anne Mößeler


    Full Text Available Although steatorrhea is the most obvious symptom of pancreatic exocrine insufficiency (PEI, enzymatic digestion of protein and starch is also impaired. Low praecaecal digestibility of starch causes a forced microbial fermentation accounting for energy losses and meteorism. To optimise dietetic measures, knowledge of praecaecal digestibility of starch is needed but such information from PEI patients is rare. Minipigs fitted with an ileocaecal fistula with (n=3 or without (n=3 pancreatic duct ligation (PL were used to estimate the rate of praecaecal disappearance (pcD of starch. Different botanical sources of starch (rice, amaranth, potato, and pea were fed either raw or cooked. In the controls (C, there was an almost complete pcD (>92% except for potato starch (61.5% which was significantly lower. In PL pcD of raw starch was significantly lower for all sources of starch except for amaranth (87.9%. Thermal processing increased pcD in PL, reaching values of C for starch from rice, potato, and pea. This study clearly underlines the need for precise specification of starch used for patients with specific dietetic needs like PEI. Data should be generated in suitable animal models or patients as tests in healthy individuals would not have given similar conclusions.

  14. Increases of 3-phosphoglyceric acid in potato plants through antisense reduction of cytoplasmic phosphoglycerate mutase impairs photosynthesis and growth, but does not increase starch contents

    Westram, A.; Lloyd, J.R.; Roessner, U.;


    in leaves were reduced, and the tuber yield of the plants was lowered. Plants with 30% of the wild-type PGAM activity in leaves and 55% in tubers showed reduced amounts of starch in tubers also. Tuber-specific reduction of PGAM expression in transgenic potato plants had no effect on starch metabolism...... and tuber yield, although the 3-PGA level was increased. This indicates that 3-PGA concentrations in potato tubers are not important for regulating ADP-glucose pyrophosphorylase activity in the production of starch under some environmental conditions.......A full-length cDNA encoding cytosolic phosphoglycerate mutase (PGAM; E.C. from potato (Solanum tuberosum L.) was isolated. RNA blots indicated that the accumulation of PGAM transcript was similar in all organs studied. Transgenic potato plants with either constitutive, or tuber...

  15. Contribution of the net charge to the regulatory effects of amino acids and epsilon-poly(L-lysine) on the gelatinization behavior of potato starch granules.

    Ito, Azusa; Hattori, Makoto; Yoshida, Tadashi; Takahashi, Koji


    The effects of lysine (Lys), monosodium glutamate (GluNa), glycine, alanine and epsilon-poly(L-lysine) (PL) with different degrees of polymerization on the gelatinization behavior of potato starch granules were investigated by DSC, viscosity and swelling measurements, microscopic observation, and measurement of the retained amino acid amount to clarify the contribution of the net charge to their regulatory effects on the gelatinization behavior. The amino acids and PL each contributed to an increase in the gelatinization temperature, and a decrease in the peak viscosity and swelling. These effects strongly depended on the absolute value of their net charge. The disappearance of a negative or positive net charge by adjusting the pH value weakened the contribution. The swelling index and size of the potato starch granules changed according to replacement of the swelling medium. The amino acids and PL were easily retained by the swollen potato starch granules according to replacement of the outer solution of the starch granules.

  16. Enhancing sucrose synthase activity in transgenic potato (Solanum tuberosum L.) tubers results in increased levels of starch, ADPglucose and UDPglucose and total yield.

    Baroja-Fernández, Edurne; Muñoz, Francisco José; Montero, Manuel; Etxeberria, Ed; Sesma, María Teresa; Ovecka, Miroslav; Bahaji, Abdellatif; Ezquer, Ignacio; Li, Jun; Prat, Salomé; Pozueta-Romero, Javier


    Sucrose synthase (SuSy) is a highly regulated cytosolic enzyme that catalyzes the conversion of sucrose and a nucleoside diphosphate into the corresponding nucleoside diphosphate glucose and fructose. To determine the impact of SuSy activity in starch metabolism and yield in potato (Solanum tuberosum L.) tubers we measured sugar levels and enzyme activities in tubers of SuSy-overexpressing potato plants grown in greenhouse and open field conditions. We also transcriptionally characterized tubers of SuSy-overexpressing and -antisensed potato plants. SuSy-overexpressing tubers exhibited a substantial increase in starch, UDPglucose and ADPglucose content when compared with controls. Tuber dry weight, starch content per plant and total yield of SuSy-overexpressing tubers increased significantly over those of control plants. In contrast, activities of enzymes directly involved in starch metabolism in SuSy-overexpressing tubers were normal when compared with controls. Transcriptomic analyses using POCI arrays and the MapMan software revealed that changes in SuSy activity affect the expression of genes involved in multiple biological processes, but not that of genes directly involved in starch metabolism. These analyses also revealed a reverse correlation between the expressions of acid invertase and SuSy-encoding genes, indicating that the balance between SuSy- and acid invertase-mediated sucrolytic pathways is a major determinant of starch accumulation in potato tubers. Results presented in this work show that SuSy strongly determines the intracellular levels of UDPglucose, ADPglucose and starch, and total yield in potato tubers. We also show that enhancement of SuSy activity represents a useful strategy for increasing starch accumulation and yield in potato tubers.

  17. 旋光法测定马铃薯淀粉含量最佳水解时间的确定%Optimal Hydrolysis Time for Potato Starch Determination Using Polarimetry



    淀粉含量的高低是评价马铃薯品质的重要指标之一.测定马铃薯淀粉含量的方法较多,其中旋光法所用仪器简单,试剂种类少,操作简便、快速,重现性好,应用广泛.为确定旋光法测定马铃薯块茎淀粉含量的最佳水解时间,以本地主栽品种‘新大坪’、‘陇薯3号’、‘陇薯6号’为试验材料,设置10,15,20,25,30 min 5个处理时间,3次重复试验,比较旋光度及淀粉含量.结果表明,水解时间为15 min时,旋光度值最大,随水解时间延长,旋光度值反而减小.由此确定,旋光法测定马铃薯块茎淀粉含量的最佳水解时间为15 min.%Starch content of potato is one of the key indexes for evaluating its quality. There are many methods for testing potato starch content, and polarimetry method employs simple devices and a few chemicals and operate sim-ply and quickly with great replication and wild applications. In order to confirm the optimal hydrolysis time of pota-to tuber starch using polarimetry method, local potato varieties of‘Xindaping’,‘Longshu 3’and‘Longshu 6’ were used as raw materials, and 10, 15, 20, 25 and 30 min were employed to compare optical rotation and starch content with three duplicates. The results showed that the optical rotation value was the largest when the hydrolysis duration was 15 min and then the value decreased with hydrolysis time. Therefore, the optimal hydrolysis time for determination of potato starch content should be 15 min.

  18. Electrical transport study of potato starch-based electrolyte system-II

    Tiwari, Tuhina; Kumar, Manindra [Department of Physics (Mahila Mahavidyalay), Banaras Hindu University, Varanasi (India); Srivastava, Neelam, E-mail: [Department of Physics (Mahila Mahavidyalay), Banaras Hindu University, Varanasi (India); Srivastava, P.C. [Department of Physics, Banaras Hindu University, Varanasi (India)


    Highlights: • Cheap and bio-degradable polymer electrolyte. • High conductivity ∼ 9.59 × 10{sup −3} Scm{sup −1}. • Detailed ion dynamics stud. -- Abstract: Glutaraldehyde (GA) crosslinked potato starch, after mixing with sodium iodide (NaI), resulted in electrolyte film having conductivity (σ) ∼ 10{sup −3} S/cm and ionic transference number (t{sub ion}) ≥ 0.99. Out of two preparation mediums, namely methanol and acetone, methanol based electrolyte system seems to be better. Super-linear power law (SLPL) phenomenon is observed in MHz frequency range and both lattice site potential and coulomb cage potential due to neighboring mobile charge carriers seems to be responsible for existence of SLPL, and variation of power law exponent ‘n’ with salt concentration. These ion dynamics results are supported by dielectric data also. Estimated number of charge carriers ‘N’ and mobility ‘μ’ are discussed with reference to different variants (medium of preparation, plasticizer, and salt content). Material's conductivity strongly depends on humidity.

  19. Bioconversion of wastewater from sweet potato starch production to Paenibacillus polymyxa biofertilizer for tea plants.

    Xu, Shengjun; Bai, Zhihui; Jin, Bo; Xiao, Runlin; Zhuang, Guoqiang


    Wastewater from the sweet potato starch industry is a large source of nutrient-rich substrates. We assessed whether this wastewater could be used to produce Paenibacillus polymyxa biofertilizer for foliar application to tea trees. Using the central composite design methods we experientially determined that the optimal culture conditions for P. polymyxa were pH, 6.5; temperature, 29.0 °C; and incubation time, 16 h. Under these conditions, a maximum biomass of 9.7 × 10(9) cfu/mL was achieved. We then conducted a yearlong field investigation to determine the effect of P. polymyxa biofertilizer on the growth of tea plants (Camellia sinensis). Tea yield, quantity of water extract, and tea polyphenol levels were significantly higher after foliar application of the biofertilizer compared to that in the controls by an average of 16.7%, 6.3%, and 10.4%, respectively. This approach appears to be technically feasible for organic tea production, and is an environmentally friendly way to utilize wastewater.

  20. Interacting effects of photoperiod and photosynthetic photon flux on net carbon assimilation and starch accumulation in potato leaves

    Stutte, G. W.; Yorio, N. C.; Wheeler, R. M.


    The effect of photoperiod (PP) on net carbon assimilation rate (Anet) and starch accumulation in newly mature canopy leaves of 'Norland' potato (Solanum tuberosum L.) was determined under high (412 varies as mol m-2s-1) and low (263 varies as mol m-2s-1) photosynthetic photon flux (PPF) conditions. The Anet decreased from 13.9 to 11.6 and 9.3 micromoles m-2s-1, and leaf starch increased from 70 to 129 and 118 mg g-1 drymass (DM) as photoperiod (PP) was increased from 12/12 to 18/6, and 24/0, respectively. Longer PP had a greater effect with high PPF conditions than with low PPF treatments, with high PPF showing greater decline in Anet. Photoperiod did not affect either the CO2 compensation point (50 micromoles mol-1) or CO2 saturation point (1100-1200 micromoles mol-1) for Anet. These results show an apparent limit to the amount of starch that can be stored (approximately 15% DM) in potato leaves. An apparent feedback mechanism exists for regulating Anet under high PPF, high CO2, and long PP, but there was no correlation between Anet and starch concentration in individual leaves. This suggests that maximum Anet cannot be sustained with elevated CO2 conditions under long PP (> or = 12 hours) and high PPF conditions. If a physiological limit exists for the fixation and transport of carbon,then increasing photoperiod and light intensity under high CO2 conditions is not the most appropriate means to maximize the yield of potatoes.

  1. Feeding a diet containing resistant potato starch influences gastrointestinal tract traits and growth performance of weaned pigs.

    Heo, J M; Agyekum, A K; Yin, Y L; Rideout, T C; Nyachoti, C M


    The aim was to evaluate the effects of feeding resistant potato starch (RPS) as a natural source of resistant starch to weaned pigs for 28 d immediately after weaning. Sixty piglets (Yorkshire-Landrace × Duroc) weaned at 21 ± 2 d (1:1 male:female) with an initial BW of 7.2 ± 0.78 kg were assigned in a completely randomized design to 1 of 5 dietary treatments to give 6 observations per treatment and 2 pigs per pen. Dietary treatments consisted of a negative control corn-soybean meal-wheat-wheat middlings-based diet (NC; no antimicrobial agents added) or the NC supplemented with RPS either as powder or in capsules and each included at 0.5 or 1.0% as a top-dressing on each day. Diets were formulated to meet 1998 NRC specifications. Pigs were offered the experimental diets on an ad libitum basis for 28 d and water was available at all times. The ADG, ADFI, and G:F were determined weekly. Fecal score was determined daily for 14 d after weaning. At the conclusion of study, 1 pig from each pen was randomly selected and euthanized (n = 6 per treatment) to determine visceral organ weight, digesta pH, VFA, and ammonia N (NH3-N) concentrations. Resistant potato starch supplementation improved (P potato starch supplementation decreased (P 0.10) in visceral organ weights, growth performance, and digestibilities of DM, CP, Ca, and P among treatments. The results of this experiment indicate that supplementing a weaner pig diet with at least 0.5% RPS independent of mode of delivery has the potential to enhance outcomes characteristic of a functional gut in weaned pigs without adverse effects on growth.

  2. Expression of an engineered granule-bound Escherichia coli glycogen branching enzyme in potato results in severe morphological changes in starch granules.

    Huang, Xing-Feng; Nazarian-Firouzabadi, Farhad; Vincken, Jean-Paul; Ji, Qin; Suurs, Luc C J M; Visser, Richard G F; Trindade, Luisa M


    The Escherichia coli glycogen branching enzyme (GLGB) was fused to either the C- or N-terminus of a starch-binding domain (SBD) and expressed in two potato genetic backgrounds: the amylose-free mutant (amf) and an amylose-containing line (Kardal). Regardless of background or construct used, a large amount of GLGB/SBD fusion protein was accumulated inside the starch granules, however, without an increase in branching. The presence of GLGB/SBD fusion proteins resulted in altered morphology of the starch granules in both genetic backgrounds. In the amf genetic background, the starch granules showed both amalgamated granules and porous starch granules, whereas in Kardal background, the starch granules showed an irregular rough surface. The altered starch granules in both amf and Kardal backgrounds were visible from the initial stage of potato tuber development. High-throughput transcriptomic analysis showed that expression of GLGB/SBD fusion protein in potato tubers did not affect the expression level of most genes directly involved in the starch biosynthesis except for the up-regulation of a beta-amylase gene in Kardal background. The beta-amylase protein could be responsible for the degradation of the extra branches potentially introduced by GLGB.

  3. Characterization of starch nanoparticles

    Szymońska, J.; Targosz-Korecka, M.; Krok, F.


    Nanomaterials already attract great interest because of their potential applications in technology, food science and medicine. Biomaterials are biodegradable and quite abundant in nature, so they are favoured over synthetic polymer based materials. Starch as a nontoxic, cheap and renewable raw material is particularly suitable for preparation of nanoparticles. In the paper, the structure and some physicochemical properties of potato and cassava starch particles of the size between 50 to 100 nm, obtained by mechanical treatment of native starch, were presented. We demonstrated, with the aim of the Scanning Electron Microscopy (SEM) and the non-contact Atomic Force Microscopy (nc-AFM), that the shape and dimensions of the obtained nanoparticles both potato and cassava starch fit the blocklets - previously proposed as basic structural features of native starch granules. This observation was supported by aqueous solubility and swelling power of the particles as well as their iodine binding capacity similar to those for amylopectin-type short branched polysaccharide species. Obtained results indicated that glycosidic bonds of the branch linkage points in the granule amorphous lamellae might be broken during the applied mechanical treatment. Thus the released amylopectin clusters could escape out of the granules. The starch nanoparticles, for their properties qualitatively different from those of native starch granules, could be utilized in new applications.

  4. Development and Identification of SSR Markers Associated with Starch Properties and β-Carotene Content in the Storage Root of Sweet Potato (Ipomoea batatas L.)

    Zhang, Kai; Wu, Zhengdan; Tang, Daobin; Lv, Changwen; Luo, Kai; Zhao, Yong; Liu, Xun; Huang, Yuanxin; Wang, Jichun


    Sweet potato (Ipomoea batatas L.) is a nutritious food crop and, based on the high starch content of its storage root, a potential bioethanol feedstock. Enhancing the nutritional value and starch quantity of storage roots are important goals of sweet potato breeding programs aimed at developing improved varieties for direct consumption, processing, and industrial uses. However, developing improved lines of sweet potato is challenging due to the genetic complexity of this plant and the lack of genome information. Short sequence repeat (SSR) markers are powerful molecular tools for tracking important loci in crops and for molecular-based breeding strategies; however, few SSR markers and marker-trait associations have hitherto been identified in sweet potato. In this study, we identified 1824 SSRs by using a de novo assembly of publicly available ESTs and mRNAs in sweet potato, and designed 1476 primer pairs based on SSR-containing sequences. We mapped 214 pairs of primers in a natural population comprised of 239 germplasms, and identified 1278 alleles with an average of 5.972 alleles per locus and a major allele frequency of 0.7702. Population structure analysis revealed two subpopulations in this panel of germplasms, and phenotypic characterization demonstrated that this panel is suitable for association mapping of starch-related traits. We identified 32, 16, and 17 SSR markers associated with starch content, β-carotene content, and starch composition in the storage root, respectively, using association analysis and further evaluation of a subset of sweet potato genotypes with various characteristics. The SSR markers identified here can be used to select varieties with desired traits and to investigate the genetic mechanism underlying starch and carotenoid formation in the starchy roots of sweet potato. PMID:26973669

  5. In planta modification of potato starch granule biogenesis by different granule-bound fusion proteins

    Nazarian, F.


    Starch is composed of amylose and amylopectin and it is deposited in amyloplasts/choloroplasts as semi-crystalline granules. Many biosynthetic enzymes are involved in starch degradation and biosynthesis. Some microbial starch degrading enzymes have a Starch Binding Domain (SBD) which has affinity fo

  6. Mixed-mode resins: taking shortcut in downstream processing of raw-starch digesting α-amylases.

    Lončar, Nikola; Šokarda Slavić, Marinela; Vujčić, Zoran; Božić, Nataša


    Bacillus licheniformis 9945a α-amylase is known as a potent enzyme for raw starch hydrolysis. In this paper, a mixed mode Nuvia cPrime™ resin is examined with the aim to improve the downstream processing of raw starch digesting amylases and exploit the hydrophobic patches on their surface. This resin combines hydrophobic interactions with cation exchange groups and as such the presence of salt facilitates hydrophobic interactions while the ion-exchange groups enable proper selectivity. α-Amylase was produced using an optimized fed-batch approach in a defined media and significant overexpression of 1.2 g L(-1) was achieved. This single step procedure enables simultaneous concentration, pigment removal as well as purification of amylase with yields of 96% directly from the fermentation broth.

  7. Production and properties of a raw-starch-degrading amylase from the thermophilic and alkaliphilic Bacillus sp. TS-23.

    Lin, L L; Chyau, C C; Hsu, W H


    The optimum temperature and initial medium pH for amylase production by Bacillus sp. TS-23 were 55 degrees C and 8.5 respectively. Maximum amylase activity was obtained in a medium containing peptone and soluble starch as nitrogen and carbon sources. Activity staining revealed that two amylases with molecular masses of 150 and 42 kDa were produced when maltose, soluble starch or amylose was used as carbon source for growth, whereas only the 150 kDa protein was detected in the medium containing water-insoluble carbon sources. A raw-starch-degrading amylase was purified from culture supernatant of Bacillus sp. TS-23. The molecular mass of the purified amylase was estimated at 42 kDa by electrophoresis. The enzyme had a pI of 4. 2. The optimal pH and temperature for activity were 9.0 and 70 degrees C respectively. The thermoactivity of the purified enzyme was enhanced in the presence of 5 mM Ca2+; under this condition, enzyme activity could be measured at a temperature of 90 degrees C. The enzyme was strongly inhibited by Hg2+, Pb2+, Zn2+, Cu2+ and EDTA, but less affected by Ni2+ and Cd2+. The enzyme preferentially hydrolysed high-molecular-mass substrates with an alpha-1, 4-glucosidic bond except glycogen. The raw starches were partly degraded by the purified amylase to yield predominantly oligosaccharides with degrees of polymerization 3, 4 and 5.

  8. Characterization of a thermostable raw-starch hydrolyzing α-amylase from deep-sea thermophile Geobacillus sp.

    Jiang, Tao; Cai, Menghao; Huang, Mengmeng; He, Hao; Lu, Jian; Zhou, Xiangshan; Zhang, Yuanxing


    A deep-sea thermophile, Geobacillus sp. 4j, was identified to grow on starch and produce thermostable amylase. N-terminally truncated form of Geobacillus sp. 4j α-amylase (Gs4j-amyA) was fused at its N-terminal end with the signal peptide of outer membrane protein A (OmpA) of Escherichia coli. The enzyme was over-expressed in E. coli BL21 with a maximum extracellular production of 130U/ml in shake flask. The yield of the transformant increased 22-fold as compared with that of the wild strain. The recombinant enzyme purified to apparent homogeneity by metal-affinity chromatography, exhibited a molecular mass of 62kDa. It displayed the maximal activity at 60-65°C and pH 5.5. Its half-life (t1/2) at 80°C was 4.25h with a temperature deactivation energy of 166.3kJ/mol. Compared to three commonly used commercial α-amylases, the Gs4j-amyA exhibited similar thermostable performance to BLA but better than BAA and BSA. It also showed a universally efficient raw starch hydrolysis performance superior to commercial α-amylases at an acidic pH approaching nature of starch slurry. As a new acidic-resistant thermostable α-amylase, it has the potential to bypass the industrial gelatinization step in raw starch hydrolysis.

  9. Characteristics of Raw Starch-Digesting α-Amylase of Streptomyces badius DB-1 with Transglycosylation Activity and Its Applications.

    Shivlata, L; Satyanarayana, T


    Streptomyces badius DB-1 produces α-amylase extracellularly, and its production was enhanced 5.1-fold (from 9.47 ± 0.51 to 48.23 ± 1.45 U mL(-1)) due to optimization by one-variable-at-a-time and statistical approaches. Soluble starch emerged as the most influential factor that strongly affected enzyme production. The purified enzyme is a monomer with a molecular mass of ~57 kDa and optimally active at 50 °C and pH 6.0. The enzyme hydrolyzes soluble as well as raw starches into simpler sugars with a high proportion (>40.0 %) of maltotetraose. It is optimally active at moderate temperature and generates maltooligosaccharides from starch, thus, useful as an antistale in bread making. It also plays a role in increasing the formation of maltooligosaccharides due to transglycosylation activity, thus, finds application in functional foods. This is the first report on the production of raw starch-digesting α-amylase by S. badius with transglycosylation activity.

  10. Preparation of oxidized carboxymethyl potato starch%氧化羧甲基马铃薯淀粉的制备



    摘要:以氧化马铃薯淀粉为原料,乙醇为溶剂,氢氧化钠为催化剂,并以取代度为评价指标,分别考察了次氯酸钠用量、一氯乙酸用量、氢氧化钠用量、反应温度、反应时间对氧化羧甲基马铃薯淀粉取代度的影响。实验结果表明,次氯酸钠量为0.823%,nCH2CICOOH:nsttch为1.02:1、nNaoHnstarh为2.19:1,醚化反应时间为58.65min(实际反应58min),在此条件下制得的氧化羧甲基马铃薯淀粉的取代度最高,达到0.278。%The optimal parameters for preparation of oxidized carboxymethyl potato starch were studied. Oxidized potato starch as material,with substitution degree as a evaluating parameter. The effects of NaCIO concentration, monochloracetic acid concentration,sodium hydroxide concentration,reaction temperature and time on the substitution degree of oxidized carboxymethyl potato starch were investigated respectively by using ethanol as solvent and sodium hydroxide as catalyst. The results showed that NaClO concentration 0.823% ,nCH2CICOOH:nsttch= 1.02:1 ,nNaoHnstarh=2.19:1 and time 58.65min(58min in fact). Under these conditions,the DS was up to 0.278.

  11. 添加剂对马铃薯淀粉糊性质的影响%Effects of Additives on the Properties of Potato Starch Paste

    朱玉; 郭丽


    To study the properties of potato starch paste, the textural properties, retrogradation and freeze-thaw stability of po-tato starch paste were studied by analytical method.Effects of sucrose, glucose and fructose on the textual properties, retrograda-tion and freeze-thaw stability of potato starch paste textural properties,retrogradation and freeze-thaw stability were investigated. The results showed that sucrose, glucose and fructose increased the gel textures of potato starch paste to the same extents.Three sugars could improve the retrogradation of potato starch paste and the retrogradation was reduced obviously with increasing sucrose contents.Besides, three sugars could improve the freeze-thaw stability of potato starch paste.%为了解马铃薯淀粉糊的性质,采用分析方法对马铃薯淀粉糊凝胶质构性、凝沉性和冻融稳定性进行探索性研究,初步考察了蔗糖、葡萄糖、果糖三种甜味剂对马铃薯淀粉糊凝胶质构性、凝沉性和冻融稳定性的影响。结果表明:蔗糖、葡萄糖、果糖均能提高马铃薯淀粉糊的凝胶质构特性,但影响程度几乎相同;三种糖类均能改善其淀粉的凝沉性,且添加浓度越高,蔗糖降低马铃薯淀粉凝沉性越明显。蔗糖、葡萄糖、果糖对马铃薯淀粉的冻融稳定性有促进作用。

  12. Effect of α-Amylase Degradation on Physicochemical Properties of Pre-High Hydrostatic Pressure-Treated Potato Starch

    Mu, Tai-Hua; Zhang, Miao; Raad, Leyla; Sun, Hong-Nan; Wang, Cheng


    The effect of high hydrostatic pressure (HHP) on the susceptibility of potato starch (25%, w/v) suspended in water to degradation by exposure to bacterial α-amylase (0.02%, 0.04% and 0.06%, w/v) for 40 min at 25°C was investigated. Significant differences (p gelatinization). These results indicate the pre-HHP treatment of NPS leads to increased susceptibility of the granules to enzymatic degradation and eventually changes of both the amorphous and the crystalline structures. PMID:26642044

  13. Study on Soaking Technology in Improving Extraction Rate of Sweet Potato Starch%提高红薯淀粉得率的浸泡工艺研究

    王家良; 陈光远; 王改玲


    为提高红薯淀粉的得率,对红薯淀粉生产过程中的不同浸渍工艺进行了研究.通过单因素试验和正交试验确定红薯干先粉碎,再浸泡的较佳工艺条件为:红薯干粉碎粒度60~100目、石灰乳用量0.05%、浸泡时间8h、浸泡温度25℃时,红薯淀粉的得率在75%左右.将红薯干直接浸泡较佳的工艺条件为:石灰乳用量0.06%、浸泡时间10 h、浸泡温度30℃时,红薯淀粉的得率在73%左右.2种工艺比较而言,将红薯干粉碎后提取淀粉,其工艺条件易于控制、提取时间缩短2h,且得率比红薯干直接浸泡提取淀粉得率提高2%.%To improve the extraction rate of sweet potato starch, the different soak technology in the production process of sweet potato starch was studied. The processing technology for extract sweet potato starch by first crush and then soaking was optimized by single - factor experiments and orthogonal experiments. The results showed that the particle size was 60 ~ 100 meshes; the dosage of lime milk was 0. 05% ; soak time was 8 h; soak temperature was 25 t ,and sweet potato starch yield was 75% or so. The optimum technology was to soak dried sweet potato as follows; the dosage of lime milk was 0.06% ;soak time was 10 h;soak temperature was 30 t, and sweet potato starch yield was 73% or so. In comparison, the production process of sweet potato starch of first crush and then soaking was easy to control with the extraction time shortened for 2 h and the rate of extraction 2% higher than the direct soaking of dried sweet potato. In order to provide a pilot basis for the industrial production of sweet potato starch.

  14. Effect of thermal and chemical modifications on the mechanical and release properties of paracetamol tablet formulations containing corn, cassava and sweet potato starches as filler-binders

    Mariam; Vbamiunomhene; Lawal; Michael; Ayodele; Odeniyi; Oludele; Adelanwa; Itiola


    Objective: To investigate the effects of acetylation and pregelatinization of cassava and sweet potato starches on the mechanical and release properties of directly compressed paracetamol tablet formulations in comparison with official corn starch.Methods: The native starches were modified by acetylation and pregelatinization. The tablets were assessed using friability(Fr), crushing strength(Cs), disintegration time(Dt) and dissolution parameters. Results: Starch acetylation produced paracetamol tablets that were stronger and had the best balance of mechanical and disintegration properties, while pregelatinization produced tablets that were more friable but had a better overall strength in relation to disintegration than formulations made from natural starches. Correlations mainly existed between Dt and the dissolution parameters t80, t2 and k1 in the formulations. Conclusions: Modification of the experimental starches improved the mechanical and release properties of directly compressed paracetamol tablet formulations. Thus, they can be developed for use as pharmaceutical excipients in specific formulations.

  15. Effect of thermal and chemical modiifcations on the mechanical and release properties of paracetamol tablet formulations containing corn, cassava and sweet potato starches as ifller-binders

    Mariam Vbamiunomhene Lawal; Michael Ayodele Odeniyi; Oludele Adelanwa Itiola


    Objective:To investigate the effects of acetylation and pregelatinization of cassava and sweet potato starches on the mechanical and release properties of directly compressed paracetamol tablet formulations in comparison with official corn starch. Methods: The native starches were modified by acetylation and pregelatinization. The tablets were assessed using friability (Fr), crushing strength (Cs), disintegration time (Dt) and dissolution parameters. Results: Starch acetylation produced paracetamol tablets that were stronger and had the best balance of mechanical and disintegration properties, while pregelatinization produced tablets that were more friable but had a better overall strength in relation to disintegration than formulations made from natural starches. Correlations mainly existed between Dt and the dissolution parameters t80, t2 and k1 in the formulations. Conclusions:Modification of the experimental starches improved the mechanical and release properties of directly compressed paracetamol tablet formulations. Thus, they can be developed for use as pharmaceutical excipients in specific formulations.

  16. A thin layer chromatographic comparison of raw and soluble starch hydrolysis patterns of some α-amylases from Bacillus sp. isolated in Serbia

    Gligorijević Nikola


    Full Text Available Several natural isolates of Bacillus strains namely 5B, 12B, 16B, 18 and 24B were grown on two different temperatures in submerged fermentation for the raw-starch-digesting a-amylases production. All strains except Bacillus sp. 18 produced more α-amylase on 37ºC. The hydrolysis of raw corn starch followed same pattern. Efficient hydrolysis was obtained with α-amylases from Bacillus sp. 5B, 12B, 16B and 24B grown on 37ºC and Bacillus sp. 18 grown on 50ºC. Zymography after isoelectric focusing shown that α-amylases were produced in multiple forms, from 2 to 6, depending on the strain when they were growing at 37 ºC, while growing at 50ºC induced only 1 or 2 isoforms. TLC analysis of hydrolysis products of raw corn and soluble starch by α-amylases revealed production of various mixtures of oligosaccharides. In most cases G3 was the most dominant product from soluble starch while G2, G3 and G5 were the main products of raw starch hydrolysis. This indicates that obtained a-amylases can be used for starch liquefying or short-chain-oligosaccharide forming, depending on what type of starch (raw or soluble was used for the hydrolysis. [Projekat Ministarstva nauke Republike Srbije, br. 172048

  17. The effect of thermal processing in oil on the macromolecular integrity and acrylamide formation from starch of three potato cultivars organically fertilized

    Theo Varzakas


    Full Text Available Starches from three organically produced cultivars of potato tuber (Lady Rosetta, Spunta and Voyager have been studied in relation to (i acrylamide production (ii macromolecular integrity after frying with extra virgin olive oil, soybean oil and corn oil. During cultivation, a treatment involving the combination of nitrogen, phosphorus and potassium fertilization under organic farming was applied (N1, P2, K1 where Ν1 = 1.3 g Ν per plant, P2 = 5.2 g P2O5 per plant, Κ1 = 4.0 g K2O per plant. Potatoes fried in olive oil retained the highest glucose concentrations for all cultivars 0.85 ± 0.2 mmol/kg, followed by 0.48 ± 0.2 for those fried in corn oil and 0.40 ± 0.1 mmol/kg for those fried in soybean oil. The highest average fructose concentration was recorded for the samples fried in corn oil as 0.81 ± 0.2, followed by 0.80 ± 0.2 and 0.68 ± 0.3 mmol/kg for the samples fried in olive and soybean oils, respectively. Asparagine was the most abundant free amino acid in the three varieties tested, followed by glutamine and aspartic acid. The mean initial concentration of asparagine in raw potatoes tubers was 42.8 ± 1.6 mmoles kg−1 for Lady Rosetta, 34.6 ± 1.2 mmoles kg−1 (dry weight for Spunta and 36.2 ± 2.0 mmoles kg−1 for Voyager. Lady Rosetta contained a significantly higher concentration of asparagine compared to the other two varieties (p < 0.05. The greatest quantity of acrylamide was observed in French fries derived from the potato variety Lady Rosetta when fried in soybean oil and it was 2,600 ± 440 μg/kg, followed by Spunta which was 2,280 ± 340 μg/kg and Voyager 1,120 ± 220 μg/kg. There is a significant reduction in the formation of acrylamide in the variety Voyager compared to the others (p = 0.05.

  18. Modification of potato starch composition by introduction and expression of bacterial branching enzyme genes.

    Kortstee, A.J.


    Starch consists of two major components; amylose and amylopectin. Amylose is synthesized by the enzyme Granule-Bound Starch Syntase (GBSS) and consists of essentially linear chains of α-1,4 linked glucose residues. Amylopectin is synthesized by the combined activity of the enzymes Soluble Starch Syn

  19. Collaborative study concerning the enzymatic determination of starch in food, feed and raw materials of the starch industry

    Brunt, K.


    This paper describes the collaborative study for establishing the repeatability and reproducibility of a recently developed new enzymatic starch determination. The ring test was in accordance to the ISO 5725 requirements for interlaboratory studies. The interlaboratory test resulted in a good relati

  20. Study on biodegradability of micronized potato starch%微细化马铃薯淀粉的生物降解性能研究

    陈玲; 胡飞; 李晓玺; 李琳


    用机械球磨方法制备不同粒度的微细化马铃薯淀粉,采用半生物体内模型系统研究它们的生物降解性能。结果表明,颗粒的微细化有利于淀粉的生物降解:微细化程度越高,淀粉越易被降解。超细马铃薯淀粉颗粒具有良好的生物降解性能。通过控制粒度大小可调节淀粉的生物降解速度和降解程度。%The biodegradability of the potato starch micronized by ball-milling was studied in terms of half-Vivo model by using micropopulation symbiotic cocultures.The results show that micronization promoted starch micro-biodegradation;the higher the micronization extent,the more easily the potato starch was degraded.The micronized potato starch granules have good biodegradability and the biodegradation rate and degree of starch can be regulated by controlling the particle size of starch.

  1. New type of starch-binding domain: the direct repeat motif in the C-terminal region of Bacillus sp. no. 195 alpha-amylase contributes to starch binding and raw starch degrading.

    Sumitani, J; Tottori, T; Kawaguchi, T; Arai, M


    The alpha-amylase from Bacillus sp. no. 195 (BAA) consists of two domains: one is the catalytic domain similar to alpha-amylases from animals and Streptomyces in the N-terminal region; the other is the functionally unknown domain composed of an approx. 90-residue direct repeat in the C-terminal region. The gene coding for BAA was expressed in Streptomyces lividans TK24. Three active forms of the gene products were found. The pH and thermal profiles of BAAs, and their catalytic activities for p-nitrophenyl maltopentaoside and soluble starch, showed almost the same behaviours. The largest, 69 kDa, form (BAA-alpha) was of the same molecular mass as that of the mature protein estimated from the nucleotide sequence, and had raw-starch-binding and -degrading abilities. The second largest, 60 kDa, form (BAA-beta), whose molecular mass was the same as that of the natural enzyme from Bacillus sp. no. 195, was generated by proteolytic processing between the two repeat sequences in the C-terminal region, and had lower activities for raw starch binding and degrading than those of BAA-alpha. The smallest, 50 kDa, form (BAA-gamma) contained only the N-terminal catalytic domain as a result of removal of the C-terminal repeat sequence, which led to loss of binding and degradation of insoluble starches. Thus the starch adsorption capacity and raw-starch-degrading activity of BAAs depends on the existence of the repeat sequence in the C-terminal region. BAA-alpha was specifically adsorbed on starch or dextran (alpha-1,4 or alpha-1,6 glucan), and specifically desorbed with maltose or beta-cyclodextrin. These observations indicated that the repeat sequence of the enzyme was functional in the starch-binding domain (SBD). We propose the designation of the homologues to the SBD of glucoamylase from Aspergillus niger as family I SBDs, the homologues to that of glucoamylase from Rhizopus oryzae as family II, and the homologues of this repeat sequence of BAA as family III.

  2. Raw starch-degrading α-amylase from Bacillus aquimaris MKSC 6.2: isolation and expression of the gene, bioinformatics and biochemical characterization of the recombinant enzyme.

    Puspasari, F; Radjasa, O K; Noer, A S; Nurachman, Z; Syah, Y M; van der Maarel, M; Dijkhuizen, L; Janeček, S; Natalia, D


    The aims were to isolate a raw starch-degrading α-amylase gene baqA from Bacillus aquimaris MKSC 6.2, and to characterize the gene product through in silico study and its expression in Escherichia coli. A 1539 complete open reading frame of a starch-degrading α-amylase gene baqA from B. aquimaris MKSC 6·2 has been determined by employing PCR and inverse PCR techniques. Bioinformatics analysis revealed that B. aquimaris MKSC 6.2 α-amylase (BaqA) has no starch-binding domain, and together with a few putative α-amylases from bacilli may establish a novel GH13 subfamily most closely related to GH13_1. Two consecutive tryptophans (Trp201 and Trp202, BaqA numbering) were identified as a sequence fingerprint of this novel GH13 subfamily. Escherichia coli cells produced the recombinant BaqA protein as inclusion bodies. The refolded recombinant BaqA protein degraded raw cassava and corn starches, but exhibited no activity with soluble starch. A novel raw starch-degrading B. aquimaris MKSC 6.2 α-amylase BaqA is proposed to be a member of new GH13 subfamily. This study has contributed to the overall knowledge and understanding of amylolytic enzymes that are able to bind and digest raw starch directly. © 2012 The Society for Applied Microbiology.

  3. Expression of an engineered granule-bound Escherichia coli glycogen branching enzyme in potato results in severe morphological changes in starch granules

    Huang, X.; Nazarian Firouzabadi, F.; Vincken, J.P.; Ji, Q.; Suurs, L.C.J.M.; Visser, R.G.F.; Trindade, L.M.


    The Escherichia coli glycogen branching enzyme (GLGB) was fused to either the C- or N-terminus of a starch-binding domain (SBD) and expressed in two potato genetic backgrounds: the amylose-free mutant (amf) and an amylose-containing line (Kardal). Regardless of background or construct used, a large

  4. Gene expression analysis of starch metabolism using mRNAseq and the potato genome sequence

    Sønderkær, Mads; Kloosterman, Bjorn; Bachem, Christian


    Crops such as potatoes that have storage organs (tubers) placed in the soil produce twice the amount of energy per area unit compared to cereals. This makes these kinds of crops well suited as a starting point for future crops for food and energy production. In order to develop a potato with high...

  5. Effect of one-step and two-step modified method on the property of cross-linked esterification sweet potato starch%一步和二步改性法对交联酯化甘薯淀粉性质的影响

    李倩; 高群玉; 吴磊


    Sodium trimetaphosphate was used as cross-linking agent and acetic anhydride as esterifying agent to prepare cross-linked esterification sweet potato starch through one-step and two-step modified method. The effect of one-step and two-step modified method on the property of cross-linked esterification sweet potato starch was compared in this study. As to one-step modified method,sweet potato starch slurry was adjusted to appropriate condition after being cross-linked and then esterified directly where wash, neutralization, dry was eliminated. As to two-step modified method, cross-linked sweet potato starch was well dried and smashed,which was used as the raw starch for the next step of esterification. Peak viscosity and stability were chosen as index and the result indicated that the cross-linked esterification sweet potato starch prepared by one-step modified method possess better peak viscosity and stability. The cross-linked esterification sweet potato starch prepared by two-step modified method possess better anti-precipitability and freezing-thaw resistance, slightly higher solubility, swelling power, but the difference between two methods was not obvious.%以三偏磷酸钠(STMP)为交联剂,醋酸酐为酯化剂,对甘薯淀粉进行复合变性,通过一步和二步改性法制备交联酯化改性甘薯淀粉。比较了一步和二步改性法对交联酯化甘薯淀粉性质的影响。一步法指甘薯淀粉交联后调整酯化的条件,省去水洗、中和与干燥操作工序连续进行酯化;二步法为将制备的交联淀粉粉碎干燥后作为酯化变性反应的原淀粉。以峰值粘度和稳定性为指标测定。结果表明:一步法改性的交联酯化甘薯淀粉具有更好的峰值粘度和稳定性;二步法改性的交联酯化甘薯淀粉具有更好的抗凝沉性,溶解度和膨胀度略高于一步法,抗冻融性更好,但与一步法差别不显著。

  6. The effects of potato and rice starch as substitutes for phosphate in and degree of comminution on the technological, instrumental and sensory characteristics of restructured ham.

    Resconi, Virginia C; Keenan, Derek F; García, Elisa; Allen, Paul; Kerry, Joe P; Hamill, Ruth M


    The effects of sodium tripolyphosphate (STPP), two sources of starch (potato starch: PS and rice starch: RS) and comminution degree (CD) on the technological, instrumental and sensory characteristics of reformed hams were studied using response surface methodology. Both starches reduced cook loss and decreased ham flavour intensity, but RS had stronger effects on instrumental measures of texture, while PS was associated with improved juiciness when low/no added STPP was included. Coarsely ground meat, processed 100% with the kidney plate was associated with slightly increased cook loss, reduced texture profile analysis parameters and a more intense ham flavour compared to the other treatment (80% ground with a kidney plate plus 20% with a 9mm plate). STPP was the sole factor affecting overall liking. If starch is included in the formulation, the standard level of STPP (0.3%) can be reduced by half with no increase in cook losses, but some decline in sensory quality cannot be avoided.

  7. 甘薯渣去除淀粉工艺研究%Study on technology of removing starch from sweet potato marc

    梁新红; 孙俊良; 唐玉; 李元召


    甘薯渣中淀粉的存在严重影响了提取果胶的纯度,因此,开发和利用薯渣中的果胶资源,必须除去甘著渣中的淀粉甘著渣中淀粉去除的最佳工艺为固液比为1∶15,甘薯渣醪液pH6.0,经高温α-淀粉酶在90℃酶解30min;然后调整pH至4.5,依次加入糖化酶、普鲁兰酶,在60℃保温酶解180min,淀粉转化率较高,达到94.22%±3.43%.根据电镜图片可知,去除淀粉效果较好.因此,甘薯渣可以采用高温α-淀粉酶、糖化酶和普鲁兰酶复合酶制剂去除淀粉.研究对甘薯果胶开发中去除甘薯渣中淀粉的工艺具有理论及实践意义.%Starch in the sweet potato marc has seriously affected the purification of sweet potato pectin,and it must be removed from the sweet potato marc. The optimal parameters of removal starch were as follows:the ratio of the sweet potato marc and water 1:15,the sweet potato marc liquid pH6.0,temperature 90℃,reaction time 30min by high temperature a -amylase,and then pH4.5,60℃,time 180min by glucoamylase and pullulase.and the conversion of starch was 94.22% ±3.43% . According to the figure of scanning electron microscope,the starch in the sweet potato marc was successfully removed. Reseach showed that it had satisfactory effect to remove the starch from the sweet potato marc by use of high temperature a-amylase, glucoamylase and pullulase. The study was of significance to remove the starch in the sweet potato marc.

  8. 薯类淀粉加工新模式--“移动方箱”%A new model of potato starch processing--“mobile box”

    李书华; 李红艳


    通过分析薯类淀粉加工工艺,提出一种新型薯类淀粉加工模式,即利用便携式薯类加工机组(简称“移动方箱”)采用“分散加工,集中干燥”的模式进行加工,并分析了此模式的优点。%This article put forward a new type of potato starch processing mode through the analysis of potato starch processing technology. The use of portable potato processing units(referred to as“mobile box")used the"decentralized processing,concentrated dry”model for processing. The advantages of this pattern were analyzed.




    The structural basis for the physical properties of starches from different botanical sources is still poorly understood. Particularly at the level of the crystalline domains the present knowledge concerning the structure of starch is limited. This paper reports the semi-crystalline structure of pot

  10. Effect of α-Amylase Degradation on Physicochemical Properties of Pre-High Hydrostatic Pressure-Treated Potato Starch.

    Mu, Tai-Hua; Zhang, Miao; Raad, Leyla; Sun, Hong-Nan; Wang, Cheng


    The effect of high hydrostatic pressure (HHP) on the susceptibility of potato starch (25%, w/v) suspended in water to degradation by exposure to bacterial α-amylase (0.02%, 0.04% and 0.06%, w/v) for 40 min at 25°C was investigated. Significant differences (p starch (PS) exposed to α-amylase (0.06%, w/v) showed a significantly greater degree of hydrolysis and amount of reducing sugar released compared to α-amylase at a concentration of 0.04% (w/v) or 0.02% (w/v). Native PS (NPS) granules have a spherical and elliptical form with a smooth surface, whereas the hydrolyzed NPS (hNPS) and hydrolyzed HHP-treated PS granules showed irregular and ruptured forms with several cracks and holes on the surface. Hydrolysis of HHP-treated PS by α-amylase could decrease the average granule size significantly (p starch in both the ordered and the amorphous structure, especially in hydrolyzed HHP600 PS. The B-type of hydrolyzed HHP600 PS with α-amylase at a concentration 0.06% (w/v) changed to a B+V type with an additional peak at 2θ = 19.36°. The HHP600 starch with 0.06% (w/v) α-amylase displayed the lowest value of To (onset temperature), Tc (conclusion temperature) and ΔHgel (enthalpies of gelatinization). These results indicate the pre-HHP treatment of NPS leads to increased susceptibility of the granules to enzymatic degradation and eventually changes of both the amorphous and the crystalline structures.

  11. Effect of α-Amylase Degradation on Physicochemical Properties of Pre-High Hydrostatic Pressure-Treated Potato Starch.

    Tai-Hua Mu

    Full Text Available The effect of high hydrostatic pressure (HHP on the susceptibility of potato starch (25%, w/v suspended in water to degradation by exposure to bacterial α-amylase (0.02%, 0.04% and 0.06%, w/v for 40 min at 25°C was investigated. Significant differences (p < 0.05 in the structure, morphology and physicochemical properties were observed. HHP-treated potato starch (PS exposed to α-amylase (0.06%, w/v showed a significantly greater degree of hydrolysis and amount of reducing sugar released compared to α-amylase at a concentration of 0.04% (w/v or 0.02% (w/v. Native PS (NPS granules have a spherical and elliptical form with a smooth surface, whereas the hydrolyzed NPS (hNPS and hydrolyzed HHP-treated PS granules showed irregular and ruptured forms with several cracks and holes on the surface. Hydrolysis of HHP-treated PS by α-amylase could decrease the average granule size significantly (p <0.05 from 29.43 to 20.03 μm. Swelling power decreased and solubility increased with increasing enzyme concentration and increasing pressure from 200-600 MPa, with the exception of the solubility of HHP-treated PS at 600 MPa (HHP600 PS. Fourier transform infrared spectroscopy (FTIR showed extensive degradation of the starch in both the ordered and the amorphous structure, especially in hydrolyzed HHP600 PS. The B-type of hydrolyzed HHP600 PS with α-amylase at a concentration 0.06% (w/v changed to a B+V type with an additional peak at 2θ = 19.36°. The HHP600 starch with 0.06% (w/v α-amylase displayed the lowest value of To (onset temperature, Tc (conclusion temperature and ΔHgel (enthalpies of gelatinization. These results indicate the pre-HHP treatment of NPS leads to increased susceptibility of the granules to enzymatic degradation and eventually changes of both the amorphous and the crystalline structures.

  12. Potato starch-blended alginate beads for prolonged release of tolbutamide: Development by statistical optimization and in vitro characterization

    Jadupati Malakar


    Full Text Available The work investigates the development and optimization of novel beads of potato starch-alginate blend containing tolbutamide by ionotropic gelation using 3 2 factorial design. The optimized beads exhibited 85.57 ± 3.24% drug encapsulation efficiency and 50.42 ± 2.18% drug release after 8 h. The in vitro drug release followed controlled-release (zero-order pattern with super case-II transport mechanism over 8 h. The swelling and degradation of the optimized beads were influenced by pH of test mediums. These were also characterized by SEM and FTIR analysis. These newly developed beads are suitable for controlled delivery of tolbutamide for prolonged period.

  13. High-pressure potato starch granule gelatinization: synchrotron radiation micro-SAXS/WAXS using a diamond anvil cell.

    Gebhardt, R; Hanfland, M; Mezouar, M; Riekel, C


    Potato starch granules have been examined by synchrotron radiation small- and wide-angle scattering in a diamond anvil cell (DAC) up to 750 MPa. Use of a 1 microm synchrotron radiation beam allowed the mapping of individual granules at several pressure levels. The data collected at 183 MPa show an increase in the a axis and lamellar period from the edge to the center of the granule, probably due to a gradient in water content of the crystalline and amorphous lamellae. The average granules radius increases up to the onset of gelatinization at about 500 MPa, but the a axis and the lamellar periodicity remain constant or even show a decrease, suggesting an initial hydration of amorphous growth rings. The onset of gelatinization is accompanied by (i) an increase in the average a axis and lamellar periodicity, (ii) the appearance of an equatorial SAXS streak, and (iii) additional short-range order peaks.

  14. Construction of Vectors to Express Foreign Protein within Potato Starch Grains%外源蛋白定位马铃薯淀粉粒表达载体的构建

    李珺; 马力通; 姚新灵


    [Objective] The aim is to study the construction of vectors expressing foreign protein in potato starch grains specifically, and provide some reference for solving industrialized core problem of high cost and low expression level of foreign protein. [Method] By using molecular biological techniques of RT-PCR and nested PCR, plant expression vector for the foreign protein locating in the potato starch grains was constructed. [Result] Coding sequence (GC20) of potato starch grains that was located and expressed by GBSSI promoter was cloned. Plant expression vector was screened out through connection, transformation and enzyme digestion identification. [Conclusion] This result laid a foundation for further screening the foreign protein on the potato starch grains.

  15. Preparation of Potato Carboxymethyl Starch%马铃薯羧甲基淀粉制备工艺的研究

    邓勇; 呙琴


    研究了以马铃薯淀粉为原料,用乙醇溶剂法制备羧甲基淀粉(CMS)。探讨了碱化温度、醚化温度、碱化时间、醚化时间、氢氧化钠用量、氯乙酸用量及反应体系中的水分含量对马铃薯羧甲基淀粉取代度(DS)的影响,通过正交试验得出制备马铃薯羧甲基淀粉的最佳工艺条件。%Carboxymethyl starch has been prepared by alcohol mediu mmethod,using potato starch as material.The effects of individual influencing f actors on DS of potato carboxymethyl starch were investigated.The technique con ditions of preparing potato carboxymethyl starch were optimized by orthogonal ex periment.

  16. Physical mapping of QTL for tuber yield, starch content and starch yield in tetraploid potato (Solanum tuberosum L.) by means of genome wide genotyping by sequencing and the 8.3 K SolCAP SNP array.

    Schönhals, Elske Maria; Ding, Jia; Ritter, Enrique; Paulo, Maria João; Cara, Nicolás; Tacke, Ekhard; Hofferbert, Hans-Reinhard; Lübeck, Jens; Strahwald, Josef; Gebhardt, Christiane


    Tuber yield and starch content of the cultivated potato are complex traits of decisive importance for breeding improved varieties. Natural variation of tuber yield and starch content depends on the environment and on multiple, mostly unknown genetic factors. Dissection and molecular identification of the genes and their natural allelic variants controlling these complex traits will lead to the development of diagnostic DNA-based markers, by which precision and efficiency of selection can be increased (precision breeding). Three case-control populations were assembled from tetraploid potato cultivars based on maximizing the differences between high and low tuber yield (TY), starch content (TSC) and starch yield (TSY, arithmetic product of TY and TSC). The case-control populations were genotyped by restriction-site associated DNA sequencing (RADseq) and the 8.3 k SolCAP SNP genotyping array. The allele frequencies of single nucleotide polymorphisms (SNPs) were compared between cases and controls. RADseq identified, depending on data filtering criteria, between 6664 and 450 genes with one or more differential SNPs for one, two or all three traits. Differential SNPs in 275 genes were detected using the SolCAP array. A genome wide association study using the SolCAP array on an independent, unselected population identified SNPs associated with tuber starch content in 117 genes. Physical mapping of the genes containing differential or associated SNPs, and comparisons between the two genome wide genotyping methods and two different populations identified genome segments on all twelve potato chromosomes harboring one or more quantitative trait loci (QTL) for TY, TSC and TSY. Several hundred genes control tuber yield and starch content in potato. They are unequally distributed on all potato chromosomes, forming clusters between 0.5-4 Mbp width. The largest fraction of these genes had unknown function, followed by genes with putative signalling and regulatory functions. The

  17. Cloning and extracellular expression of a raw starch digesting α-amylase (Blamy-I) and its application in bioethanol production from a non-conventional source of starch.

    Roy, Jetendra K; Manhar, Ajay K; Nath, Dhrubajyoti; Mandal, Manabendra; Mukherjee, Ashis K


    The aim of this study was to clone and efficiently express a raw starch-digesting α-amylase enzyme in the culture media and also to investigate the potential application of this recombinant enzyme in the digestion of non-conventional raw starch for bioethanol production. A raw starch digesting α-amylase gene isolated from Bacillus licheniformis strain AS08E was cloned and extracellularly expressed in E. coli cells using the native signal peptide. The mature recombinant α-amylase (Blamy-I) consisting of 483 amino acid residues was found to be homogenous with a mass of 55.3 kDa (by SDS-PAGE analysis) and a predicted pI of 6.05. Structural and functional analysis of Blamy-I revealed the presence of an extra Ca(2+) -binding region between the A and C domains responsible for higher thermostability of this enzyme. The statistical optimization of E. coli culture conditions resulted in an approximately eightfold increase in extracellular expression of Blamy-I as compared to its production under non-optimized conditions. Blamy-I demonstrated optimum enzyme activity at 80 °C and pH 10.0, and efficiently hydrolyzed raw starch isolated from a non-conventional, underutilized jack fruit seeds. Further utilization of this starch for bioethanol production using Blamy-I and Saccharomyces cerevisiae also proved to be highly promising.

  18. Influence of hydration and starch digestion on the transient rheology of an aqueous suspension of comminuted potato snack food.

    Boehm, Michael W; Warren, Frederick J; Moore, Jackson E; Baier, Stefan K; Gidley, Michael J; Stokes, Jason R


    Oral processing of most foods is inherently destructive: solids are broken into particles before reassembly into a hydrated bolus while salivary enzymes degrade food components. In order to investigate the underlying physics driving changes during oral processing, we capture the transient rheological behaviour of a simulated potato chip bolus during hydration by a buffer with or without α-amylase. In the absence of amylase and for all oil contents and solids weight fractions tested, we find a collapse of the transient data when graphed according to simple Fickian diffusion. In the presence of amylase, we find effects on the transient and pseudo steady state bolus rheology. Within the first minute of mixing, the amylase degrades only ≈6% of the starch but that leads to an order of magnitude reduction in the bolus elasticity, as compared to the case without amylase. Thus, for an in vitro bolus, only a small amount of starch needs to be digested to have a large impact on the bolus rheology very soon after mixing.

  19. Decreasing the mitochondrial synthesis of malate in potato tubers does not affect plastidial starch synthesis, suggesting that the physiological regulation of ADPglucose pyrophosphorylase is context dependent.

    Szecowka, Marek; Osorio, Sonia; Obata, Toshihiro; Araújo, Wagner L; Rohrmann, Johannes; Nunes-Nesi, Adriano; Fernie, Alisdair R


    Modulation of the malate content of tomato (Solanum lycopersicum) fruit by altering the expression of mitochondrially localized enzymes of the tricarboxylic acid cycle resulted in enhanced transitory starch accumulation and subsequent effects on postharvest fruit physiology. In this study, we assessed whether such a manipulation would similarly affect starch biosynthesis in an organ that displays a linear, as opposed to a transient, kinetic of starch accumulation. For this purpose, we used RNA interference to down-regulate the expression of fumarase in potato (Solanum tuberosum) under the control of the tuber-specific B33 promoter. Despite displaying similar reductions in both fumarase activity and malate content as observed in tomato fruit expressing the same construct, the resultant transformants were neither characterized by an increased flux to, or accumulation of, starch, nor by alteration in yield parameters. Since the effect in tomato was mechanistically linked to derepression of the reaction catalyzed by ADP-glucose pyrophosphorylase, we evaluated whether the lack of effect on starch biosynthesis was due to differences in enzymatic properties of the enzyme from potato and tomato or rather due to differential subcellular compartmentation of reductant in the different organs. The results are discussed in the context both of current models of metabolic compartmentation and engineering.

  20. Morphology, transport characteristics and viscoelastic polymer chain confinement in nanocomposites based on thermoplastic potato starch and cellulose nanofibers from pineapple leaf.

    Balakrishnan, Preetha; Sreekala, M S; Kunaver, Matjaž; Huskić, Miroslav; Thomas, Sabu


    Eco-friendly "green" nano composites were fabricated from potato starch and cellulose nanofibers from pineapple leaf. Nanocomposites of starch/cellulose nanofibers were prepared by solution mixing followed by casting. The investigation of the viscoelastic properties confirms starch macromolecular chain confinement around the nano scale cellulose surface, superior dispersion and very good interaction between thermoplastic starch and cellulose nanofibers. The degree of chain confinement was quantified. The chain confinement was associated with the immobilization of the starch macromolecular chains in the network formed by the nano-scale cellulose fibers as a result of hydrogen boding interactions. From the results, it was assumed that the starch glycerol system exhibits a heterogenous nature and cellulose nanofibers tend to move towards glycerol rich starch phase. Barrier properties also improved with the addition of nanofiller up to 3wt.% but further addition depreciated properties due to possible fiber agglomeration. The kinetics of diffusion was investigated and typical kinetic parameters were determined and found that the nanocomposites follow pseudo fickian behaviour. The outcome of the work confirms that the prepared nanocomposites films can be used as a swap for packaging applications. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. Binding of the Trace Elements: Cu(II) and Fe(III) to the Native and Modified Nutritive Potato Starches Studied by EPR

    Śmigielska, H.; Lewandowicz, G.; Goslar, J.; Hoffmann, S. K.


    The Cu(II) and Fe(III) ions have been adsorbed by four potato starches of different degrees of oxidation (different numbers of COOH groups replacing host CH2OH groups): native (no oxidized), white (pudding) with oxidation degree of 0.04%, gelating (0.1%), and LUBOX starch (0.5%). Concentration of the ions in starches was determined from atomic absorption and EPR spectrum intensity. For small concentration of the adsorbed ions (below 4 mg/g) nearly all ions are adsorbed from the solution. EPR shows that adsorbed copper(II) ions are chemically bonded to the starch molecules (preferably) at COOH sites and uniformly dispersed in the starch structure. The complexes are typical of octahedral or square-quadratic coordination with spin-Hamiltonian parameters gǁ=2.373, g⊥= 2.080, Aǁ=12.1 mT, A⊥=1.0 mT. For higher concentrations the Cu(II) displays a tendency to clustering. Iron(III) ions are introduced into starch in a form of clusters mainly, even for the smallest concentration. The highest concentrations of both Cu(II) and Fe(III) were observed in LUBOX starch having the highest degree of oxidation.

  2. 银杏果淀粉与玉米、马铃薯淀粉理化性质的比较研究%Comparison of physical and chemical properties of ginkgo starchand corn,potato starch

    李新华; 杨强; 王琳; 刘爽


    The physical and chemical properties of the ginkgo fruit starch extracted in the laboratory were studied,and compared with the corn starch and potato starch.The results showed that the transparency,solubility,turgidity of ginkgo starch were higher than corn starch,lower than potato starch;the retrogradation,freeze-thaw stability were superior to corn starch,worse than potato starch;starch milk concentration,shear force,medium had effect on the viscosity of ginkgo starch.%以实验室提取的银杏果淀粉为原料,对其性质进行研究,并与玉米淀粉和马铃薯淀粉的性质进行了比较。结果表明,银杏果淀粉的透明度、溶解度、膨胀度比玉米淀粉高,比马铃薯淀粉低;凝沉性、冻融稳定性比玉米淀粉强,比马铃薯淀粉差;淀粉乳浓度、剪切力、介质对银杏果淀粉的黏度都有影响。

  3. Agrobacterial rol genes modify thermodynamic and structural properties of starch in microtubers of transgenic potato

    Aksenova, N.P.; Wasserman, L.A.; Sergeeva, L.I.; Konstantinova, T.N.; Golyanovskaya, S.A.; Krivandin, A.V.; Plashchina, I.G.; Blaszczak, W.; Fornal, J.; Romanov, G.A.


    Wild-type (WT) plants of potato (Solanum tuberosum L.) and their transgenic forms carrying agrobacterial genes rolB or rolC under the control of B33 class I patatin promoter were cultured in vitro on MS medium with 2% sucrose in a controlled-climate chamber at 16-h illumination and 22A degrees C. Th

  4. Expression of different glucansucrases in potato tubers: implications for starch biosynthesis

    Kok-Jacon, G.A.


    This thesis describes the production of dextran (polymers with -(1→6)-linked glucosyl residues), mutan (polymers with -(1→3)-linked glucosyl residues) and alternan (polymers with alternating -(1→3)/ -(1→6)-linked glucosyl residues) in potato tubers. Modifications of the physicochemical properties of

  5. Experimental study on the rheological properties of starch gels of buckwheat, corn and potato%荞麦、玉米、马铃薯淀粉凝胶特性的试验研究

    汪小芳; 李小昱; 王为


    利用电子万能材料试验机对荞麦、玉米、马铃薯淀粉的力学特性进行了研究.结果表明:在一定范围内,随着淀粉乳浓度的增加,荞麦、玉米、马铃薯的凝胶强度、弹性模量和凝胶弹性呈线性增加,但凝胶弹性变化较小;同一淀粉乳浓度下凝胶强度由高到低顺序为马铃薯淀粉>玉米淀粉>荞麦淀粉,弹性模量为马铃薯淀粉>玉米淀粉>荞麦淀粉,凝胶弹性为荞麦淀粉>玉米淀粉>马铃薯淀粉.在淀粉乳浓度为20%时,随着NaCl浓度增加,3种淀粉的凝胶强度均有一定程度增强.在同一NaCl浓度下,其凝胶强度为马铃薯淀粉>玉米淀粉>荞麦淀粉,弹性模量为马铃薯淀粉>玉米淀粉>荞麦淀粉,对凝胶弹性的影响不大.%The mechanical properties of starch gels of buckwheat, corn and potato were tested with All-purpose Electronic Tester. The test results show that the gel strength, elastic modulus and gel elasticity of buckwheat starch, corn starch and potato starch increase linearly with the increase of starch concentration, while the increase trend of gel elasticity changes little. Under the condition of the same starch concentration, the gel strength, elastic modulus and gel elasticity of three different starches behave in different orders: the gel strength and elastic modulus of starch follows the same trend, the first is potato starch and the last is buckwheat starch; while the gel elasticity of starch order is reverse, the first is buckwheat starch and the last is potato starch. When the starch concentration is 20%, the gel strengths of three starches increase with the increase of NaCl concentration. Under the condition of same NaCl concentration, the gel strength and elastic modulus of starch follow the same trend, the first is potato starch and the last is buckwheat starch; but it has little effect on gel elasticity.

  6. Controlling rheology and structure of sweet potato starch noodles with high broccoli powder content by hydrocolloids

    Silva, E.; Birkenhake, M.; Scholten, E.; Sagis, L.M.C.; Linden, van der E.


    Incorporating high volume fractions of broccoli powder in starch noodle dough has a major effect on its shear modulus, as a result of significant swelling of the broccoli particles. Several hydrocolloids with distinct water binding capacity (locust bean gum (LBG), guar gum, konjac glucomannan (KG),

  7. Improved production of raw starch degrading enzyme by Aspergillus oryzae F-30 using methyl glucoside sesqui-stearate.

    Sun, Hai-Yan; Wang, Lu; Liu, Jian-Wen; Peng, Ming


    The effect of methyl glucoside sesqui-stearate (MGS) on the production of raw starch degrading enzyme (RSDE) by Aspergillus oryzae F-30 was studied in this paper. The activity of RSDE formed by Aspergillus oryzae F-30 was enhanced dramatically by the addition of MGS to the medium. As a result, with the addition of 1.5 g MGS in 1 L basal medium, RSDE activity and productivity were 107 U mL(-1) and 1.49 U mL(-1) h(-1), 4.3-fold and 7.1-fold greater than the values obtained in the basal medium, respectively. The effect of MGS on the synthesis of RSDE by Aspergillus oryzae F-30 was also studied on a molecular level. It was observed that the regulation of RSDE synthesis in Aspergillus oryzae F-30 occurs at both transcriptional and translational level and the enzyme synthesis was provoked by the addition of MGS at transcriptional level.

  8. The production of a new fungal alpha-amylase degraded the raw starch by means of solid-state fermentation.

    Balkan, Bilal; Ertan, Figen


    In this study, it was intended to produce a new fungal amylase by solid-state fermentation and purification and also to determine some of its biochemical properties. It was found that Penicillium brevicompactum had the best enzyme activity according to screening methods with amylase degrading raw starch, and P. brevicompactum was selected as the amylase source. Wheat bran, rice husks, and sunflower oil meal were tested to determine the best solid substrate. Wheat bran was determined as the best of these. The fermentation conditions were optimized for the production of amylase. The optimum fermentation conditions were found to be an initial moisture level for the solid substrate of 55%, moistening agent of 0.1 M sodium phosphate buffer (pH 5.0), incubation period of 7 d, inoculum concentration of 2.5 mL, and incubation temperature at 30 degrees C. Penicillium brevicompactum alpha-amylase was purified 45.98 times by the starch affinity method. The K(m) and V(max) values of alpha-amylase for soluble starch were 5.71 mg/mL and 666.6 U/mL, respectively. This amylase showed maximum activity at between 30 and 50 degrees C and at pH 5.0. Initial enzyme activity was kept at 100% after incubation at 30 degrees C for 45 min. Enzyme was stable in the pH range of 4.0-5.0. This enzyme was activated by Mn(2+), Cu(2+), and Na(+) ions, and was inhibited by Mg(2+), K(+), Fe(3+), and ethylenediamine tetraacetic acid (EDTA). The molecular mass of P. brevicompactum alpha-amylase was found to be 32.5 kD by sodium dodecyl sulfate (SDS) polyacrylamide gel electrophoresis.

  9. Prediction of Starch, Soluble Sugars and Amino Acids in Potatoes (Solanum tuberosum L.) Using Hyperspectral Imaging, Dielectric and LF-NMR Methodologies

    Kjær, Anders; Nielsen, Glenn; Stærke, Søren


    was designed to evaluate five different scanning methods for their potential use in potato assessment and sorting. Two methods were based on hyperspectral imaging, two were based on dielectric/bio-impedance and one was based on low-field nuclear magnetic resonance. A set of 60 potatoes of 10 different......, conductivity of pressed cell sap and cell sizes. Results showed that most types of spectral analyses had relatively high potential for predicting the starch-related parameters and medium potential for predicting the concentration of the reducing sugars fructose and glucose. Most methods showed medium potential...... for prediction of several amino acids, including asparagine, which showed particularly promising predictions in the hyperspectral analyses of intact potatoes. The presented screening study enabled us to perform robust choices for the further development and optimization of the methods and instruments...

  10. Production of raw-starch-digesting α-amylase isoform from Bacillus sp. under solid-state fermentation and biochemical characterization.

    Božić, Nataša; Slavić, Marinela Šokarda; Gavrilović, Anja; Vujčić, Zoran


    α-Amylase production by solid-state fermentation of different Bacillus sp. was studied previously on different fermentation media. However, no study has been reported on the influence of selected media on expression of desired amylase isoforms such as raw-starch-digesting amylase (RSDA). In this paper, the influence of different inexpensive and available agro-resources as solid media (corn, wheat and triticale) on α-amylase isoform induction from three wild-type Bacillus sp., selected among one hundred strains tested, namely 9B, 12B and 24A was investigated. For all three strains, tested amylases were detected in the multiple forms; however, number and intensity of each form differed depending on the solid media used for growth. To determine which isoform from Bacillus sp. 12B was RSDA, the suspected isoform was purified. The optimum pH for the purified α-amylase isoform was 6.0-8.0, while the optimum temperature was 60-90 °C. Isoform was considerably thermostable and Ca(2+)-independent, and actually the only α-amylase active towards raw starch. Purification and characterization of RSDA showed that not all of the solid media tested induced RSDA. From an economic point of view, it might be significant to obtain pure isoenzyme for potential use in the raw-starch hydrolysis, since it was 5 times more efficient in raw corn starch hydrolysis than the crude amylase preparation.

  11. Production of raw starch-degrading enzyme by Aspergillus sp. and its use in conversion of inedible wild cassava flour to bioethanol.

    Moshi, Anselm P; Hosea, Ken M M; Elisante, Emrode; Mamo, Gashaw; Önnby, Linda; Nges, Ivo Achu


    The major bottlenecks in achieving competitive bioethanol fuel are the high cost of feedstock, energy and enzymes employed in pretreatment prior to fermentation. Lignocellulosic biomass has been proposed as an alternative feedstock, but because of its complexity, economic viability is yet to be realized. Therefore, research around non-conventional feedstocks and deployment of bioconversion approaches that downsize the cost of energy and enzymes is justified. In this study, a non-conventional feedstock, inedible wild cassava was used for bioethanol production. Bioconversion of raw starch from the wild cassava to bioethanol at low temperature was investigated using both a co-culture of Aspergillus sp. and Saccharomyces cerevisiae, and a monoculture of the later with enzyme preparation from the former. A newly isolated strain of Aspergillus sp. MZA-3 produced raw starch-degrading enzyme which displayed highest activity of 3.3 U/mL towards raw starch from wild cassava at 50°C, pH 5.5. A co-culture of MZA-3 and S. cerevisiae; and a monoculture of S. cerevisiae and MZA-3 enzyme (both supplemented with glucoamylase) resulted into bioethanol yield (percentage of the theoretical yield) of 91 and 95 at efficiency (percentage) of 84 and 96, respectively. Direct bioconversion of raw starch to bioethanol was achieved at 30°C through the co-culture approach. This could be attractive since it may significantly downsize energy expenses.


    N. R. Andreev


    Full Text Available Summary. The analysis of structure of starch containing raw materials processing in Russia Federation is provided in the article. There was noted an increase in volumes of corn and wheat processing, however the share of processed potato is still low (below 4%. It was established that Russian starch products and starch sweeteners are on the same level on quality as best European samples and they are very competitive. Market demand in crystalline glucose for food and medical purposes (over 30 thous. tons is fully covered by import. The volume of import of modified starches exceeds 80 % of total consumption. The biggest volume of import among native starches belongs to potato starch – over 60 %. The article provides suggestions on import substitution of mentioned starch products. The growth of starch production in Russia was accompanied by concentration of production at large enterprises. So, in 2013 over 90 % of glucose syrup was produced at six enterprises, over 80 % of dry starch – at five enterprises. Efficiency of corn and wheat processing into starch and starch products is achieved by production and selling of co-products (dry gluten, gluten, corn germ or corn oil, corn extract, feed products.Development of starch sweeteners production from starch could be achieved by expanding the consumption areas of different kinds of glucose syrup and production of glucose-fructose syrups as full substitute of sugar, providing import substitution of sugar, crystalline glucose of food and medicine purpose, deep processing of glucose into polyols (sorbit, maltit, polylactites, aminoacids.

  13. 电解法和微波法联合处理提高甘薯淀粉回生率%Increasing Retrogradation Rate of Sweet Potato Starch by Method of Combined Electrolysis and Microwave Treatment

    连喜军; 钱瑞; 刘敬; 赵娟; 肖学勇; 刘洋


    以甘薯淀粉为原料,采用电解、微波复合法制备回生抗性淀粉;以抗性淀粉制备率为考察指标,讨论微波、电解顺序对回生抗性淀粉制备产率的影响。最佳工艺为:淀粉→糊化→高压→微波→电解→老化→酶解→离心→干燥;最佳工艺参数:淀粉乳质量浓度50 g/L,高压温度120℃,高压时间30 min,糊化温度90℃,糊化时间30min,微波功率400 W,处理时间4 min,电解电压90 V,电解时间2 min,老化温度4℃,老化时间12 h。在此工艺条件下,甘薯回生抗性淀粉产率为24%,比空白组12%产率提高了1倍。%Taking sweet potato starch as raw material and retrogradation rate as an inspection target,the effects of sequence of microwave wave and electrolysis treatments on retrogradation rate of sweet potato were discussed in this experiment.The best process sequence was: Starch→ Pasting → Autoclaving → Microwave → Electrolysis → Aging → Hydrolysis → Centrifugal →Drying and the best technical factors were: ratio of starch and water 5%,high-pressured temperature and treating time 120 ℃,30 min,pasting temperature and treating time 90 ℃,30 min,microwave power and treating time 400 W,4 min,Electrolytic voltage and treating time 90 V,2 min,aging temperature 4 ℃,aging time 12 h.The highest retrogradation rate of sweet potato starch at the optimum conditions was 24%,which was 100% higher than that of control group 12%.

  14. Pretreatment of fermentation feed for lactic acid production. Liquefaction of potato starch in lactic acid solution; Nyusan hakko genryo no maeshori ni kansuru kenkyu. Nyusan ni yoru bareisho denpunshitsu no ekika

    Morita, M.; Yokota, Y. [Hokkaido National Industrial Research Institute, Sapporo (Japan)


    The liquefaction of potato starchy catalyzed by lactic acid produced in a fermentation process, was carried out as a means for pretreating lactic acid fermentation feed. Liquefaction yield and molecular weight distribution of liquefied starch fractions were largely dependent on pH values of solution. The feed was effectively liquefied in lactic acid solution, of which pH value was less than 3.5, under sterilization conditions of 388 K and 30 min. Starch in potato or its waste was also hydrolyzed into smaller molecular weight fractions, compared to soluble starch commercially available. The potato starch liquefaction proposed is considered to be a useful method for pretreatment of lactic acid fermentation feed. 2 refs., 3 figs., 1 tab.

  15. Efficient sorption of Cu(2+) by composite chelating sorbents based on potato starch-graft-polyamidoxime embedded in chitosan beads.

    Dragan, Ecaterina Stela; Apopei Loghin, Diana Felicia; Cocarta, Ana Irina


    Ionic composites based on cross-linked chitosan (CS) as matrix and poly(amidoxime) grafted on potato starch (AOX) as entrapped chelating resin were prepared as beads, for the first time in this work, by two strategies: (1) thorough mixing of previously prepared AOX in the CS solution followed by the bead formation and (2) thorough mixing of the potato starch-g-poly(acrylonitrile) (PS-g-PAN) copolymer in the initial CS solution, followed by bead formation, the amidoximation of the nitrile groups taking place inside the beads. Ionotropic gelation in tripolyphosphate was used to obtain the composite beads, and in situ covalent cross-linking by epichlorohydrin was carried out to stabilize the beads in the acidic pH range. Fourier transform infrared spectroscopy and the swelling ratio values in the acidic pH range confirmed the influence of the synthesis strategy on the structure of the CS/AOX composites. Scanning electron microscopy was employed to reveal the morphology of the novel composites, both before and after their loading with Cu(2+). The binding capacity of Cu(2+) ions as a function of sorbent composition, synthesis strategy, pH, sorbent dose, contact time, initial concentration of Cu(2+), and temperature was examined in batch mode. The main difference between the composites prepared with the two strategies consisted of the higher sorption capacity and the much faster settlement of the equilibrium sorption for the composite prepared by the in situ amidoximation of PS-g-PAN. The Langmuir, Freundlich, Temkin, Dubinin-Radushkevich, and Sips isotherms were applied to fit the sorption equilibrium data. The maximum equilibrium sorption capacity, qm, evaluated by the Langmuir model at 25 °C was 133.15 mg Cu(2+)/g for the CS/AOX composite beads prepared with the first strategy and 238.14 mg Cu(2+)/g for the CS/AOX composite beads prepared with the second strategy, at the same AOX content. The pseudo-second order kinetic model well fitted the sorption kinetics data

  16. Non-additive response of blends of rice and potato starch during heating at intermediate water contents: A differential scanning calorimetry and proton nuclear magnetic resonance study.

    Bosmans, Geertrui M; Pareyt, Bram; Delcour, Jan A


    The impact of different hydration levels, on gelatinization of potato starch (PS), rice starch (RS) and a 1:1 blend thereof, was investigated by differential scanning calorimetry and related to nuclear magnetic resonance proton distributions of hydrated samples, before and after heating. At 20% or 30% hydration, the visual appearance of all samples was that of a wet powder, and limited, if any, gelatinization occurred upon heating. At 30% hydration, changes in proton distributions were observed and related to plasticization of amorphous regions in the granules. At 50% hydration, the PS-RS blend appeared more liquid-like than other hydrated samples and showed more pronounced gelatinization than expected based on additive behavior of pure starches. This was due to an additional mobile water fraction in the unheated PS-RS blend, originating from differences in water distribution due to altered stacking of granules and/or altered hydration of PS due to presence of cations in RS.

  17. Enzymatic hydrolysis of potato pulp

    Mariusz Lesiecki


    Full Text Available Background. Potato pulp constitutes a complicated system of four types of polysaccharides: cellulose, hemicellulose, pectin and starch. Its composition makes it a potential and attractive raw material for the production of the second generation bioethanol. The aim of this research project was to assess the usefulness of commercial enzymatic preparations for the hydrolysis of potato pulp and to evaluate the effectiveness of hydrolysates obtained in this way as raw materials for ethanol fermentation. Material  and methods. Sterilised potato pulp was subjected to hydrolysis with commercial enzymatic preparations. The effectiveness of the preparations declared as active towards only one fraction of potato pulp (separate amylase, pectinase and cellulase activity and mixtures of these preparations was analysed. The monomers content in hydrolysates was determined using HPLC method. Results.  The application of amylolytic enzymes for potato pulp hydrolysis resulted in the release of only 18% of raw material with glucose as the dominant (77% constituent of the formed product. In addition, 16% galactose was also determined in it. The hydrolysis of the cellulose fraction yielded up to 35% raw material and the main constituents of the obtained hydrolysate were glucose (46% and arabinose (40%. Simultaneous application of amylolytic, cellulolytic and pectinolytic enzymes turned out to be the most effective way of carrying out the process as its efficiency in this case reached 90%. The obtained hydrolysate contained 63% glucose, 25% arabinose and 12% other simple substances. Conclusion. The application of commercial enzymatic preparations made it possible to perform potato pulp hydrolysis with 90% effectiveness. This was achieved by the application of a complex of amylolytic, cellulolytic and pectinolytic enzymes and the hydrolysate obtained in this way contained, primarily, glucose making it a viable substrate for ethanol fermentation.

  18. Growth temperature of different local isolates of Bacillus sp. in the solid state affects production of raw starch digesting amylases

    Šokarda-Slavić Marinela


    Full Text Available Natural amylase producers, wild type strains of Bacillus sp., were isolated from different regions of Serbia. Strains with the highest amylase activity based on the starch-agar plate test were grown on solid-state fermentation (SSF on triticale. The influence of the substrate and different cultivation temperature (28 and 37°C on the production of amylase was examined. The tested strains produced α-amylases when grown on triticale grains both at 28 and at 37°C, but the activity of amylases and the number and intensity of the produced isoforms were different. Significant hydrolysis of raw cornstarch was obtained with the Bacillus sp. strains 2B, 5B, 18 and 24B. The produced α-amylases hydrolyzed raw cornstarch at a temperature below the temperature of gelatinization, but the ability for hydrolysis was not directly related to the total enzyme activity, suggesting that only certain isoforms are involved in the hydrolysis. [Projekat Ministarstva nauke Republike Srbije, br. 172048

  19. 马铃薯变性淀粉替换原淀粉的比例对法兰克福香肠品质的影响%Effects of Substitution Rate of Modified Potato Starch to Native Potato Starch on Sensory and Physico-chemical Properties of Frankfurters

    姚鸿宇; 贺旺林; 霍光; 俞龙浩


    In order to study the effects of modified potato starch and native potato starch proportion to frankfurters quality,the proportion 0%,20%,40%,60%,80%and 100%of native potato starch were substituted for the modified starch to make frankfurters, and the moisture content,water activity,color,hardness,elasticity,chewiness,sticky,restorative,gumminess,cohesiveness and sensory properties of frankfurters were analyzed. The results showed that the comprehensive quality of frankfurter sausage was the best under condition of replacement rate 40%.%为了研究马铃薯变性淀粉替换马铃薯原淀粉的比例对法兰克福香肠品质的影响,将马铃薯淀粉以0%、20%、40%、60%、80%、100%比率替换成马铃薯变性淀粉制作法兰克福香肠,测定其水分含量、水分活度、色泽、硬度、弹性、咀嚼性、黏性、恢复性、胶着性、凝聚力和感官指标并分析结果。结果表明:当替换率为40%时,法兰克福香肠的综合品质最佳。

  20. Two carbon fluxes to reserve starch in potato (Solanum tuberosum L.) tuber cells are closely interconnected but differently modulated by temperature.

    Fettke, Joerg; Leifels, Lydia; Brust, Henrike; Herbst, Karoline; Steup, Martin


    Parenchyma cells from tubers of Solanum tuberosum L. convert several externally supplied sugars to starch but the rates vary largely. Conversion of glucose 1-phosphate to starch is exceptionally efficient. In this communication, tuber slices were incubated with either of four solutions containing equimolar [U-¹⁴C]glucose 1-phosphate, [U-¹⁴C]sucrose, [U-¹⁴C]glucose 1-phosphate plus unlabelled equimolar sucrose or [U-¹⁴C]sucrose plus unlabelled equimolar glucose 1-phosphate. C¹⁴-incorporation into starch was monitored. In slices from freshly harvested tubers each unlabelled compound strongly enhanced ¹⁴C incorporation into starch indicating closely interacting paths of starch biosynthesis. However, enhancement disappeared when the tubers were stored. The two paths (and, consequently, the mutual enhancement effect) differ in temperature dependence. At lower temperatures, the glucose 1-phosphate-dependent path is functional, reaching maximal activity at approximately 20 °C but the flux of the sucrose-dependent route strongly increases above 20 °C. Results are confirmed by in vitro experiments using [U-¹⁴C]glucose 1-phosphate or adenosine-[U-¹⁴C]glucose and by quantitative zymograms of starch synthase or phosphorylase activity. In mutants almost completely lacking the plastidial phosphorylase isozyme(s), the glucose 1-phosphate-dependent path is largely impeded. Irrespective of the size of the granules, glucose 1-phosphate-dependent incorporation per granule surface area is essentially equal. Furthermore, within the granules no preference of distinct glucosyl acceptor sites was detectable. Thus, the path is integrated into the entire granule biosynthesis. In vitro C¹⁴C-incorporation into starch granules mediated by the recombinant plastidial phosphorylase isozyme clearly differed from the in situ results. Taken together, the data clearly demonstrate that two closely but flexibly interacting general paths of starch biosynthesis are functional

  1. Estimation of biogas and methane yields in an UASB treating potato starch processing wastewater with backpropagation artificial neural network.

    Antwi, Philip; Li, Jianzheng; Boadi, Portia Opoku; Meng, Jia; Shi, En; Deng, Kaiwen; Bondinuba, Francis Kwesi


    Three-layered feedforward backpropagation (BP) artificial neural networks (ANN) and multiple nonlinear regression (MnLR) models were developed to estimate biogas and methane yield in an upflow anaerobic sludge blanket (UASB) reactor treating potato starch processing wastewater (PSPW). Anaerobic process parameters were optimized to identify their importance on methanation. pH, total chemical oxygen demand, ammonium, alkalinity, total Kjeldahl nitrogen, total phosphorus, volatile fatty acids and hydraulic retention time selected based on principal component analysis were used as input variables, whiles biogas and methane yield were employed as target variables. Quasi-Newton method and conjugate gradient backpropagation algorithms were best among eleven training algorithms. Coefficient of determination (R(2)) of the BP-ANN reached 98.72% and 97.93% whiles MnLR model attained 93.9% and 91.08% for biogas and methane yield, respectively. Compared with the MnLR model, BP-ANN model demonstrated significant performance, suggesting possible control of the anaerobic digestion process with the BP-ANN model.

  2. Characterization of an organic solvent-tolerant thermostable glucoamylase from a halophilic isolate, Halolactibacillus sp. SK71 and its application in raw starch hydrolysis for bioethanol production.

    Yu, Hui-Ying; Li, Xin


    A halophilic bacterium Halolactibacillus sp. SK71 producing extracellular glucoamylase was isolated from saline soil of Yuncheng Salt Lake, China. Enzyme production was strongly influenced by the salinity of growth medium with maximum in the presence of 5% NaCl. The glucoamylase was purified to homogeneity with a molecular mass of 78.5 kDa. It showed broad substrate specificity and raw starch hydrolyzing activity. Analysis of hydrolysis products from soluble starch by thin-layer chromatography revealed that glucose was the sole end-product, indicating the enzyme was a true glucoamylase. Optimal enzyme activity was found to be at 70°C, pH 8.0, and 7.5% NaCl. In addition, it was highly active and stable over broad ranges of temperature (0-100°C), pH (7.0-12.0), and NaCl concentration (0-20%), showing excellent thermostable, alkali stable, and halotolerant properties. Furthermore, it displayed high stability in the presence of hydrophobic organic solvents. The purified glucoamylase was applied for raw corn starch hydrolysis and subsequent bioethanol production using Saccharomyces cerevisiae. The yield in terms of grams of ethanol produced per gram of sugar consumed was 0.365 g/g, with 71.6% of theoretical yield from raw corn starch. This study demonstrated the feasibility of using enzymes from halophiles for further application in bioenergy production.

  3. Utilization starch of jackfruit seed (Artocarpus heterophyllus) as raw material for bioplastics manufacturing using sorbitol as plasticizer and chitosan as filler

    Lubis, M.; Harahap, M. B.; Manullang, A.; Alfarodo; Ginting, M. H. S.; Sartika, M.


    Starch is a natural polymer that can be used for the production of bioplastics because its source is abundant, renewable and easily degraded. Jackfruit seeds can be used as raw material for bioplastics because its contains starch. The aim of this study to determine the characteristics of jackfruit seeds and determine the effect of chitosan and sorbitol on the physicochemical properties of bioplastics from jackfruit seeds. Starch is extracted from jackfruit seeds were then characterized to determine its chemical composition. In the manufacture of bioplastics starch composition jackfruit seeds - chitosan used was 7: 3, 8: 2 and 9: 1 (g/g), while the concentration of sorbitol used was 20%, 25%, 30%, 35%, and 40% by weight dry ingredients. From the analysis of jackfruit seed starch obtained water content of 6.04%, ash content of 1.08%, the starch content of 70.22%, 16.39% amylose content, amylopectin content of 53.83%, 4.68% protein content, fat content 0.54%. The best conditions of starch bioplastics jackfruit seeds obtained at a ratio of starch: chitosan (w/w) = 8: 2 and the concentration of plasticizer sorbitol 25% with tensile strength 13.524 MPa. From the results of FT-IR analysis indicated an increase for the OH group and the group NH on bioplastics due to the addition of chitosan and sorbitol. The results of mechanical tests is further supported by analysis of scanning electron microscopy (SEM) showing jackfruit seed starch has a small granule size with the size of 7.6 μm and in bioplastics with chitosan filler and plasticizer sorbitol their fracture surface is smooth and slightly hollow compared bioplastics without fillers chitosan and plasticizer sorbitol.

  4. Diffusion-Limited Aggregation in Potato Starch and Hydrogen Borate Electrolyte System

    Tuhina Tiwari


    Full Text Available Natural growth of diffusion-limited aggregate (DLA, without any external stimuli, in boric acid doped starch system is reported here. Fractals grown were confirmed to be of diffusion-limited aggregate (DLA pattern having fractal dimension ~1.49. Effect of substrate and humidity on growth pattern has also been discussed. The existence of a different vibration band of H3BO3 in FTIR confirmed that growth structures are related to boric acid. XRD pattern has shown broad peak along with some sharp peaks. Broad peak is related to starch’s amorphous nature, as where intense sharp peaks are due to boric acid.

  5. Differences between the Bud End and Stem End of Potatoes in Dry Matter Content, Starch Granule Size, and Carbohydrate Metabolic Gene Expression at the Growing and Sprouting Stages.

    Liu, Bailin; Zhang, Guodong; Murphy, Agnes; De Koeyer, David; Tai, Helen; Bizimungu, Benoit; Si, Huaijun; Li, Xiu-Qing


    Potatoes usually have the tuber bud end dominance in growth during tuber bulking and in tuber sprouting, likely using carbohydrates from the tuber stem end. We hypothesized that the tuber bud end and tuber stem end coordination in carbohydrate metabolism gene expression is different between the bulking dominance and sprouting dominance of the tuber bud end. After comparing the growing tubers at harvest from a green vine and the stage that sprouts just started to emerge after storage of tubers at room temperature, we found the following: (1) Dry matter content was higher in the tuber stem end than the tuber bud end at both stages. (2) The starch granule size was larger in the tuber bud end than in the tuber stem end. (3) The tuber bud end had higher gene expression for starch synthesis but a lower gene expression of sucrose transporters than the tuber stem end during tuber growing. (4) The tuber stem end at the sprouting stage showed more active gene expression in both starch degradation and resynthesis, suggesting more active export of carbohydrates, than the tuber bud end. The results indicate that the starch accumulation mechanism in the tuber bud end was different between field growing and post-harvest sprouting tubers and that tubers already increased dry matter and average starch granule sizes in the tuber bud end prior to the rapid growth of sprouts.

  6. Preparation of Fat Substitute using Enzymatic Denatured Potato Starch%酶解马铃薯淀粉制备脂肪模拟品的研究

    丛美娟; 郭华


    利用马铃薯淀粉制备酶变性淀粉,在单因素试验的基础上选择了淀粉浆浓度、酶解温度、酶解时间进行三因素三水平的正交试验,确定了较优的淀粉酶解工艺条件,使酶解淀粉的DE值稍大于2.再确定酶变性淀粉的糊化温度和糊化时间,制备用来模拟油脂的变性淀粉,以减少食用者的热量摄入,更加有利于人体健康.%Potato starch was used to prepare enzymatic denatured starch. On the basis of single factor experiments, three factors( chose concentration of starch slurry, enzymatic hydrolysis temperature and enzyme hydrolysis time) were chosen for orthogonal experiment to determine the optimum process conditions of amylase solution to keep DE value being of higher than 2. And then the pasting temperature and pasting time of enzymatic denatured starch were determined. Using enzymatic modified starch to simulate the oil in food can reduce the intake of calories and was more benefit health.

  7. 马铃薯氧化淀粉制备及在食品中的应用进展%Preparation and application of oxidized potato starch in food industry

    张高鹏; 吴立根; 屈凌波; 刘亚伟; 刘洁


    马铃薯氧化淀粉是马铃薯淀粉与氧化剂在一定温度、时间、pH等作用下产生的一种淀粉衍生物。该文论述了以次氯酸盐、过氧化氢、高锰酸钾、二氧化氯等氧化剂制备马铃薯氧化淀粉的最佳工艺,阐述了马铃薯氧化淀粉在焙烤食品、蒸煮食品、油炸食品、冷冻食品等中的应用,并展望马铃薯氧化淀粉在食品行业中的发展趋势。%Oxidized potato starch is a starch derivativeof potato starch andoxidants in the roleof acertain temperature,time,pH andotherconditions. In this paper,theoxidized starch preparation processoptimization with hypochlorite,hydrogen peroxide,potassium permanganate,chlorine dioxide asoxidation were reviewed,and the applicationsofoxidized potato starch were discussed in bakery products,steamed foods,fried foods,frozen foods and soon. Lastly this paper focusedon looking forward to the development prospects and trendsofoxidized potato starch in the food industry.

  8. Effects of Variation in Activities of Starch-Sugar Metabolic Enzymes on Reducing Sugar Accumulation and Processing Quality of Potato Tubers

    CHENG Shan-han; SU Zhen-hong; XIE Cong-hua; LIU Jun


    The experiment was designed,via storing potato tubers of cv.E-Potatol and E-Potato3 in different temperatures,to explore the variation patterns of reducing sugar(RS)and total sugar(TS)contents and enzyme activities that are involved in the pathway of starch-sugar metabolism aiming at identifying the main factors that influence the chip color.The results showed that low temperature in storage was a main factor that accelerated the accumulation of RS of the stored tubers and a very significant linear relationship existed between RS content and chip color index(CCI)of the tubers.Further analysis elucidated that when tubers stored at 4℃,the activities of ADP glucose pyrophosphorylase(AGPase),UDP glucose pyrophosphorylase(UGPase)and sucrose synthase(SuSy)were negatively exponential to the RS content significantly while that of acid invertase and alkaline invertase was significantly linear to RS content.It suggested that these enzymes could play main roles in the cold sweetening of potato tubers through regulating starch-sugar metabolism.

  9. Genomic prediction of starch content and chipping quality in tetraploid potato using genotyping-by-sequencing

    Sverrisdóttir, Elsa; Byrne, Stephen; Sundmark, Ea Høegh Riis


    Genomic selection uses genome-wide molecular markers to predict performance of individuals and allows selections in the absence of direct phenotyping. It is regarded as a useful tool to accelerate genetic gain in breeding programs, and is becoming increasingly viable for crops as genotyping costs...... genomic estimated breeding values. Cross-validated prediction correlations of 0.56 and 0.73 were obtained within the training population for starch content and chipping quality, respectively, while correlations were lower when predicting performance in the test panel, at 0.30–0.31 and 0.......42–0.43, respectively. Predictions in the test panel were slightly improved when including representatives from the test panel in the training population but worsened when preceded by marker selection. Our results suggest that genomic prediction is feasible, however, the extremely high allelic diversity of tetraploid...

  10. Consumers Preferences to Sweet Potato Flakes (Spf from Sweet Potato Pasta as A Raw Material, with Enrichment Mung Bean Flour as Source Protein

    Noveria Sjafrina


    Full Text Available Sweet potato flakes as an alternative food and a source of carbohydrates as breakfast cereals food. To meet the nutritional needs of sweet potato flakes contained in the primarily source of protein. The purpose of the research was a source of enrichment of protein contained in sweet potato flakes (SPF with the addition of mung bean flour.  And to get an optimal result of consumer preferences with the addition of mung bean flour optimal still be accepted by consumers based on organoleptic test. This study consists of several stages, namely the stage of making sweet potato pasta base material, formulation, manufacture flakes and organoleptic product. Experimental design using a completely randomized design, 5 treatment composition of sweet potato pasta and mung bean flour were (95 : 5%, (90 : 10%,(85 : 15%,(80: 20% and(75: 25% with 3 replications. The best formula will be determined by organoleptic and physical and chemical analysis. Data were collected for chroma color, moisture content, proximat, crispness (texture and resistance crisp during the presentation of the milk solution. Sweet potato flakes was getting a balanced nutritional content and better nutrional content after enrichment with mung bean flour protein content  Sweet potato flakes which become water content 5.6713% - 6.2435%, ash content 2.7501% - 3.0858%, 4.4765% protein content up to 9,0908%, carbohydrate content of 80.2744% - 85.7119%. The level of enrichment of proteins by the addition of mung bean flour to sweet potato flakes most preferred and acceptable panelists as consumer to the addition of 10% mung bean flour.

  11. Digestion by pigs of non-starch polysaccharides in wheat and raw peas (Pisum sativum) fed in mixed diets.

    Goodlad, J S; Mathers, J C


    The digestion by pigs of non-starch polysaccharides (NSP) in wheat and raw peas (Pisum sativum) fed in mixed diets was measured. In the four experimental diets, wheat was included at a constant 500 g/kg whilst peas contributed 0-300 g/kg and these were the only dietary sources of NSP. Separate estimates of digestibility for wheat and peas were obtained by using a multiple linear regression technique which also tested the possibility that the presence of peas might influence the digestibility of wheat NSP. There was little evidence of the latter and it was found that the digestibility of peas NSP (0.84) was considerably greater than that of wheat (0.65). The non-cellulosic polysaccharides (NCP) had twofold greater digestibilities than had cellulose for both foods with essentially all the peas NCP being digested. Faecal alpha, epsilon-diaminopimelic acid concentration increased with feeding of peas, suggesting stimulation of bacterial biomass production in the large intestine using the readily fermented peas NSP. All three major volatile fatty acids produced by large intestinal fermentation were detected in jugular blood and increased significantly with increasing peas inclusion rate in the diet.

  12. 中国甘薯淀粉产业发展现状与前景展望%Situation and Prospect of Sweet Potato Starch Processing Industry in China

    戴起伟; 钮福祥; 孙健; 曹静


    The current status and problems of sweet potato starch processing industry in China were analyzed and the development countermeasures and prospects were also put forward in this paper. At present, the processing method of sweet potato starch in China is still in the family-style small workshop, the small and medium-sized enterprises machinery processing, while the large enterprise with mechanized automation processing is in developing. Shandong and Henan as well as other provinces are the sweet potato starch production concentrated areas. The restricting factors in the development of sweet potato starch industry mainly included technology backward, high energy consumption, big environmental pollution, low rate of comprehensive utilization for by-product, etc.. The development of sweet potato starch processing industry in the future should be strived to promote large-scale and intensive, to fundamentally change the way of small and scattered processing, meanwhile, to further strengthen the high sweet potato starch variety breeding and special machinery innovation and technology research for sweet potato starch processing, to highly improve the efficiency of sweet potato starch processing and to raise the economic output.%对中国当前甘薯淀粉加工产业现状和问题进行了分析,提出了发展对策和前景展望。目前中国甘薯淀粉加工方式仍然以家庭作坊式、中小型企业机械加工为主,大型企业自动化加工已开始起步。山东、河南等省是目前中国甘薯淀粉生产比较集中的地区。影响甘薯淀粉产业发展的主要制约因素是技术工艺落后、能耗高、环境污染大、副产物综合利用率低等。今后甘薯淀粉产业发展应着力推进规模化、集约化,从根本上改变小而散的加工方式,同时加强高淀粉甘薯品种选育及专用型甘薯淀粉加工机械研制与工艺创新,进一步提高甘薯淀粉加工产出率和经济效益。

  13. Study on Comminution Process and Micronization Efficiency of Potato Starch by Ball Milling%马铃薯淀粉的球磨破碎方式和微细化效果研究


    采用机械球磨方法对马铃薯淀粉进行微粉碎,研究了球磨过程中淀粉颗粒的形貌、粒度分布及比表面积的变化特征,探讨了淀粉颗粒的破碎方式和粉碎模型,并考察了马铃薯淀粉微细化的效果。%Potato starch is mechanically ground by ball milling.The granular appearance,granule size distribution and specific surface of the starch are studied before and after milling.The comminution process and micronization effciency of the starch are discussed based on ultra-micronization model.The results show that potato starch can be effectively micronized by ball milling.

  14. [Effects of antisense acid invertase gene on reducing sugar and starch contents of potato (Solanum tuberosum L.) tuber stored at low temperature].

    Wang, Qing; Huang, Hui-Ying; Zhang, Jin-Wen; Li, Xue-Cai


    Two transgenic potato lines with antisense AcInv gene and the non-transgenic varieties were used to test the reducing sugar and starch contents. The results indicated that the reducing sugar content increased and total starch content decreased in all samples after tubers were stored at 4 degrees C for 40 d. The reducing sugar content in tubers of transgenic line "Anti-AcInv Atlantic" and "Anti-AcInv Gannongshu No.2" were lower about 23% and 18% than those of Atlantic and Gannongshu No.2 (Table 1). The total starch and the amylopectin were also decreased by 1% and 1.3% in "Anti-AcInv Atlantic" and 1.4% and 1.7% in "Anti-AcInv Gannongshu No.2" respectively (Table 2). The proportions of amylose and amylopectin were lower in the transgenic lines than the non-transgenic varieties (Figs. 1 and 2). It was only 0.29 for "Anti-AcInv Atlantic" and 0.38 for "Anti-AcInv Gannongshu No.2". Meanwhile, there are fewer dark blue starch particles in transgenic tuber, which is less than in tuber of the non-transgenic varieties by paraffin-cut section method (Fig. 3). After the tubers were transferred to the storage temperature 15-17 degrees C for 20 d, the reducing sugar contents in tubers of the two transgenic lines were significantly lower than that of non-transgenic varieties. It was 0.23% for "Anti-AcInv Atlantic" and 0.24% for "Anti-AcInv Gannongshu No.2" (Table 1). It is suggested that the trans-antisense AcInv gene in the transgenic potato down-regulates the AcInv gene expression after the tubers were stored under low temperature.

  15. Effects of three cyclodextrins on physicochemical properties and digestibility of sweet potato starch%三种环糊精对红薯淀粉理化性质和消化性影响

    李学红; 陈智静; 陆勇; 聂钰洪


    将α–、β–、γ–环糊精分别按照一定比例加入到红薯淀粉中,研究三种环糊精对红薯淀粉糊透光率、冻融稳定性、老化程度的影响。结果表明:随着红薯淀粉中三种环糊精用量的增加,红薯淀粉糊的透光率先增加后减小、冻融稳定性得到改善、老化程度减小。随着三种环糊精用量的增加,三种环糊精改性红薯淀粉中的直链淀粉含量呈减小趋势,快消化淀粉(RDS)含量先减小后增加,慢消化淀粉(SDS)含量先增加后减小,抗性淀粉(RS)含量先增加后减小。其中加入2%β–环糊精改性的红薯淀粉的慢消化淀粉含量最高,达到了31.09%。%Theα–,β–,γ–cyclodextrin were respectively added to sweet potato starch with acertain scale to study the effectsof threecyclodextrinson the transmittance,freeze–thaw stability,aging degree of sweet potato starch.The results showed that the transmittanceof sweet potato starch increased first and then decreased,the freeze–thaw stabilityof sweet potato starch improved,the aging degreeof sweet potato starch decreased with the increaseofcyclodextrin.The amylosecontentofmodified sweet potato starch decreased,the rapidly digestible starch(RDS) decreased first and then increased,the slowly digestible starch(SDS) increased first and then decreased,the resistant starch(RS) increased first and then decreased with the increaseofcyclodextrin.The largest slowly digestible starchcontentof sweet potato starchmodified byβ–cyclodextrin was 31.09% when thecontentof β–cyclodextrin was 2%.

  16. Structure of the complex of a yeast glucoamylase with acarbose reveals the presence of a raw starch binding site on the catalytic domain.

    Sevcík, Jozef; Hostinová, Eva; Solovicová, Adriana; Gasperík, Juraj; Dauter, Zbigniew; Wilson, Keith S


    Most glucoamylases (alpha-1,4-D-glucan glucohydrolase, EC have structures consisting of both a catalytic and a starch binding domain. The structure of a glucoamylase from Saccharomycopsis fibuligera HUT 7212 (Glu), determined a few years ago, consists of a single catalytic domain. The structure of this enzyme with the resolution extended to 1.1 A and that of the enzyme-acarbose complex at 1.6 A resolution are presented here. The structure at atomic resolution, besides its high accuracy, shows clearly the influence of cryo-cooling, which is manifested in shrinkage of the molecule and lowering the volume of the unit cell. In the structure of the complex, two acarbose molecules are bound, one at the active site and the second at a site remote from the active site, curved around Tyr464 which resembles the inhibitor molecule in the 'sugar tongs' surface binding site in the structure of barley alpha-amylase isozyme 1 complexed with a thiomalto-oligosaccharide. Based on the close similarity in sequence of glucoamylase Glu, which does not degrade raw starch, to that of glucoamylase (Glm) from S. fibuligera IFO 0111, a raw starch-degrading enzyme, it is reasonable to expect the presence of the remote starch binding site at structurally equivalent positions in both enzymes. We propose the role of this site is to fix the enzyme onto the surface of a starch granule while the active site degrades the polysaccharide. This hypothesis is verified here by the preparation of mutants of glucoamylases Glu and Glm.

  17. Chemical modification with phthalic anhydride and chitosan: Viable options for the stabilization of raw starch digesting amylase from Aspergillus carbonarius.

    Nwagu, Tochukwu Nwamaka; Okolo, Bartholomew; Aoyagi, Hideki; Yoshida, Shigeki


    The raw starch digesting type of amylase (RSDA) presents greater opportunities for process efficiency at cheaper cost and shorter time compared to regular amylases. Chemical modification is a simple and rapid method toward their stabilization for a wider application. RSDA from Aspergillus carbonarius was modified with either phthalic anhydride (PA) or chitosan. Activity retention was 87.3% for PA-modified and 80.9% for chitosan-modified RSDA. Optimum pH shifted from 5 to 7 after PA-modification. Optimum temperature changed from 30°C (native) to 30-40°C and 60°C for PA-modified and chitosan-modified, respectively. Activation energy (kJmol(-1)) for hydrolysis was 13.5, 12.7, and 10.2 while the activation energy for thermal denaturation was 32.8, 80.3, 81.9 for free, PA-modified and chitosan-modified, respectively. The specificity constants (Vmax/Km) were 73.2 for PA-modified, 63.1 for chitosan-modified and 77.1 for native RSDA. The half-life (h) of the RSDA at 80°C was increased from 6.1 to 25.7 for the PA-modified and 138.6 for the chitosan derivative. Modification also led to increase in D value, activation enthalpy and Gibbs free energy of enzyme deactivation. Fluorescence spectra showed that center of spectral mass decreased for the PA-modified RSDA but increased for chitosan modified RSDA. Copyright © 2017 Elsevier B.V. All rights reserved.

  18. Stabilization of a raw starch digesting amylase from Aspergillus carbonarius via immobilization on activated and non-activated agarose gel.

    Nwagu, Tochukwu N; Okolo, Bartho N; Aoyagi, Hideki


    Applications of raw starch digesting amylases (RSDAs) are limited due to instability, product inhibition of enzyme and contamination. RSDA from Aspergillus carbonarius was stabilized through immobilization on agarose gel by adsorption, spontaneous crosslinking and conjugation using glycidol, glutaraldehyde or polyglutaraldehyde. Effects of immobilization on kinetics, catalytic, storage and operational stability of immobilized enzyme were evaluated. Polyglutaraldehyde activated agarose RSDA (PGAg-RSDA) gave the highest immobilization yield (100%) with expressed activity of 86.7% while that of glycidol activated RSDA (GlyAg-RSDA) was 80.4%. A shift in pH from optimum of 5 for the soluble enzyme to 6 for RSDA adsorbed on agarose followed by crosslinking with glutaraldehyde (AgRSDA-CROSS) and simultaneous adsorption and crosslinking (AgRSDA-RET), and pH 7 for PGAg-RSDA was seen. PGAg-RSDA and AgRSDA-CROSS were most pH stable and retained over 82% of their activities between pH 3.5 and 9 compared to 59% for the soluble enzyme. Thermoinactivation studies showed that immobilized RSDAs with the exception of GAg-RSDA retained over 90% of their activities at 60°C for 120 min while soluble enzyme retained only 76% activity under the same condition. AgRSDA-CROSS, PGAg-RSDA, Gly-RSDA and GAg-RSDA retained approximately 100% of their activities after 30 days storage at 4°C. GlyAg-RSDA retained 99.6%, PGAg-RSDA 94%, AgRSDA-CROSS 90%, GAg-RSDA 86.5% and Ag-RSDA-RET 80% activity after 10 batch reactions. Immobilization stabilized RSDA and permits processing at higher temperatures to reduce contamination.

  19. Stabilization of a raw-starch-digesting amylase by multipoint covalent attachment on glutaraldehyde-activated amberlite beads.

    Nwagu, Tochukwu N; Okolo, Bartho N; Aoyagi, Hideki


    Raw-starch-digesting enzyme (RSDA) was immobilized on Amberlite beads by conjugation of glutaraldehyde/ polyglutaraldehyde (PG)-activated beads or by crosslinking. The effect of immobilization on enzyme stability and catalytic efficiency was evaluated. Immobilization conditions greatly influenced the immobilization efficiency. Optimum pH values shifted from pH 5 to 6 for spontaneous crosslinking and sequential crosslinking, to pH 6-8 for RSDA covalently attached on polyglutaraldehyde-activated Amberlite beads, and to pH 7 for RSDA on glutaraldehyde-activated Amberlite. RSDA on glutaraldehyde-activated Amberlite beads had no loss of activity after 2 h storage at pH 9; enzyme on PG-activated beads lost 9%, whereas soluble enzyme lost 65% of its initial activity. Soluble enzyme lost 50% initial activity after 3 h incubation at 60 degrees C, whereas glutaraldehyde-activated derivative lost only 7.7% initial activity. RSDA derivatives retained over 90% activity after 10 batch reuse at 40 degrees C. The apparent Km of the enzyme reduced from 0.35 mg/ml to 0.32 mg/ml for RSDA on glutaraldehyde-activated RSDA but increased to 0.42 mg/ml for the PG-activated RSDA derivative. Covalent immobilization on glutaraldehyde Amberlite beads was most stable and promises to address the instability and contamination issues that impede the industrial use of RSDAs. Moreover, the cheap, porous, and non-toxic nature of Amberlite, ease of immobilization, and high yield make it more interesting for the immobilization of this enzyme.

  20. Characterization of biotechnological processes and products using high-performance liquid chromatography (HPLC). Pt. 2. Analyses of potato starch hydrolysis products

    Gey, M.; Becker, U.


    Potato starch hydrolysis products were analyzed for glucose, maltose, higher oligomeric carbohydrates (to a degree of polymerization, dp 11) and 5-hydroxymethylfurfural (HMF) using high-performance liquid chromatography. For quick qualitative and quantitative analyses short glass columns (12) of high efficiency were useful. The hydrolyses were carried out by means of enzymes (e.g. ..cap alpha..- and ..beta..-amylase) or mineral acids. For the acid degradation procedures hydrochloric acid, sulfuric acid and phosphoric acid of different concentrations (0.1...2.0 N) during times ranging from 5 to 60 min at temperatures ranging from 100 to 140/sup 0/C were used. Maximum glucose contents (163.4 g/l and 169.3 g/l) were found after 40 to 50 min of hydrolysis in 0.1 N hydrochloric acid heated to 120/sup 0/C. These values are equivalent to 78.9% or 81.7% glucose yield referred to the initial potato starch amount, respectively. The calculated HMF concentrations were 140 and 180 mg/l.

  1. Effects of Paclobutrazoi on Yield and Starch Content of Potato%多效唑对马铃薯产量和淀粉含量的影响

    李云亚; 杨如鸿


    At medium-term growth stages of potato,different concentrations of paclobutrazol were sprayed on leaves to study its effect on the agronomic traits, yield and starch content of potato. The results showed that paclobutrazol could dwarf the plant,inhibit the growth of stem, make leaf green, strengthen the photosynthesis of leaf and nutrient accumulation, improve root tuber expanding, and increase the yield and starch content of potato. In all treatments,the effects of spraying concentration 400 mg/L of 15% paelobutrazol solution at rate of 600 kg/hm2 were the best, and the yield of potato reached 16 572.22 kg/hm2, and increased 26.94% compared to the control. The starch content was 19.48%, and increased by 12.54% compared with the control.%在马铃薯生长中期以不同浓度的多效唑溶液进行叶面喷施,研究多效唑对马铃薯农艺性状、产量及淀粉舍量的影响。结果表明,马铃薯喷施多效唑能矮化植株,抑制地上茎杆生长,使植株叶色浓绿,增强光合作用,增加营养积累,促进薯块膨大,从而提高马铃薯的产量和淀粉含量,其中以喷施400mg/L的15%多效唑溶液600kg/hm2的处理效果最好,产量为16572.22kg/hm2,比对照增产3516.66kg/hm2,增幅为26.94%,淀粉含量最高迭19.48%,比对照增长12.54%。

  2. Discussion on the Factors Influencing the Results of Potato Starch Ash Determination%马铃薯淀粉灰分测定结果的影响因素及讨论

    席建甲; 田映良; 王艇弘


    本文对原淀粉灰分的组成、原理及常用方法进行概述,并结合实际,对影响马铃薯淀粉灰分测定结果的因素进行分析讨论,以及对测定马铃薯淀粉灰分的温度和时间进行筛选,并最终确定800℃为测定马铃薯淀粉灰分的最适温度,在国标的基础上优化了测定马铃薯灰分的条件。%The paper overviewed the composition, theory and methods of ash starch, combined with practice, analyzed and discussed the factors affecting the potato starch ash measurement results, as well as filtrated the temperature and time of potato starch ash determination, and finally determined that 800 ℃ is the optimum temperature of potato starch ash determination and optimized the conditions for the determination of potato ash on the basis of the national standard.

  3. Competitiveness study of potato starch industry based on gray correlation analysis in Gansu Province%灰色关联分析的甘肃马铃薯淀粉产业竞争力研究

    史永良; 杜英; 张爱宁; 张建韬


    基于对甘肃马铃薯淀粉产业发展现状的分析,探讨影响马铃薯淀粉产业竞争力的主要因素,在此基础上,建立竞争力评价指标体系,在对各评价指标独立比较研究的基础上,运用灰色关联分析方法对我国马铃薯淀粉主产区综合竞争力进行测算,基于测算结果,对甘肃马铃薯淀粉产业竞争力状况进行分析研究.%Based on analysis of the potato starch development in Cansu Province, the impact factors of the potato starch industry competitive were explored. On this basis, the industry competitiveness evaluation index system was established based on independent evaluation. The competitiveness of the potato starch in the main producing areas of China was estimated by grey correlation analysis; moreover, the situation of potato starch industry competitiveness in Gansu Province was analyzed based on the calculation results.

  4. Research status and development of the treatment of wastewater containing highly concentrated potato starch%高浓度马铃薯淀粉废水处理工艺研究现状及发展

    俞年丰; 唐运平; 许丹宇; 石岩; 陈斌


    The water quality characteristics and pollution factors of the wastewater containing highly concentrated potato starch are both analyzed. The conventional treatment process and feasibility analysis of potato starch wastewater in China and abroad nowadays are introduced. By means of analyzing the climate in North China and production characteristics of potato starch, the new technology of MYR (membrane yeast reactor) is put forward. The results show that MYR is suitable for treating potato starch wastewater in the north of China efficiently.%分析了高浓度马铃薯淀粉废水的水质特性及污染因子,介绍了目前国内外对高浓度马铃薯淀粉废水的传统处理工艺及可行性分析.通过对北方气候和马铃薯淀粉生产特点的分析,提出适合此特点的膜酵母反应器处理淀粉废水新工艺.结果表明,膜酵母反应器处理工艺适合北方马铃薯淀粉废水的高效处理.

  5. Repression of a novel isoform of disproportionating enzyme (stDPE2) in potato leads to inhibition of starch degradation in leaves but not tubers stored at low temperature

    Lloyd, J.R.; Blennow, A.; Burhenne, K.


    and tubers. Transgenic potato plants were made in which its presence was almost completely eliminated. It could be demonstrated that starch degradation was repressed in leaves of the transgenic plants but that cold-induced sweetening was not affected in tubers stored at 4degreesC. No evidence could be found...

  6. 马铃薯淀粉纳米颗粒与牛血清蛋白相互作用研究%Study of the interaction between potato starch nanoparticles and bovine serum protein

    王效金; 张兆丽


    通过制备马铃薯淀粉纳米颗粒,经紫外–可见光谱、荧光色谱分析,探讨了马铃薯淀粉纳米颗粒与牛血清蛋白(BSA)之间的相互作用。紫外–可见光谱显示,马铃薯淀粉纳米颗粒浓度达0.05 mg/mL时,BSA在278 nm处的波峰消失;荧光色谱显示,马铃薯淀粉纳米颗粒的加入引起了BSA在波长340 nm处所产生的发射峰强度下降,揭示了牛血清蛋白和纳米淀粉颗粒之间产生了一定的相互作用。%In this study,the potato starch nanoparticles were fabricated and the interaction between potato starch nanoparticles and bovine serum albumin(BSA)was explored by UV–visible spectroscopy and fluorescence chromatography. The UV–visible spectroscopy showed that the BSA absorption peak in the wavelength of 278 nm disappeared when potato starch nanoparticles was added at a concentration of 0.05 mg/mL;The fluorescence chromatography results showed that the addition of potato starch nanoparticles caused a decrease of BSA emission peak in the wavelength of 340 nm. The results suggested that there was a strong interaction between potato starch nanoparticles and BSA.

  7. 南疆引种马铃薯不同生态条件下的淀粉含量与淀粉产量%Starch Content and Starch Yield of Seven Introduced Potato Varieties under Different Ecological Environments of South Xinjiang

    韩秀锋; 郭伟锋; 王冀川; 王有武; 石瑛


    [目的]研究南疆引种的马铃薯(Solanum tuberosum)在不同生态条件下的淀粉含量及淀粉产量,以确定特定生态地区适宜种植的马铃薯品种类型,为种植者及加工企业跨地区引种栽培马铃薯提供科学依据.[方法]将南疆引种的7个不同马铃薯品种在南疆2种不同生态类型的新疆建设兵团农一师四团和九团2个地区进行种植,进行淀粉含量和淀粉产量的测定和评价.[结果]费乌瑞它是淀粉含量高且稳定性比较好的品种,定选2号是淀粉含量最低且稳定性比较差的品种.在四团和九团淀粉产量比较高的品种是大西洋和费乌瑞它.[结论]马铃薯品种自身的遗传特性对淀粉含量起主导作用,而生态条件对淀粉产量形成起着重要作用.%[Objective] The purpose was to analyze starch content and starch yield of introduced potato varieties under different ecological environments of South Xinjiang, to confirm the suitable potato varieties in special ecological areas, and to provide a scientific basis for introducing and cultivating the other areas potato of planter and process enterprises. [ Method ] Seven introduced potato varieties of South Xinjiang were planted in two different ecological environments, the Fourth and Ninth Regimen of the First Division of Xinjiang Production and Construction Corps, and determined and evaluated their starch content and starch yield. [ Result] Feiwuruita has high starch content and good stability with starch yield, while Dingxuan2hao has the lowest starch content and worse stability relatively with starch yield. The varieties with high starch yield were Atlantic and Feiwruita. [ Conclusion] The hereditary characters of potato varieties play a leading role in their starch content, while the ecological environments play an important role in forming of starch yield.

  8. Effects of Zinc and Phosphorus on Nutrients, Starch and Reducing Sugar Concentrations of Potato Tubers under with or without Water Deficit Stress

    rahim motalebifard


    Full Text Available Introduction: In natural environments, plants are subjected to biotic (insects, bacteria, fungi, and viruses and abiotic (light, temperature, water availability, nutrients, and soil structure stresses that can have negative effect on growth, metabolism, and yield. Among these, drought is a major abiotic factor that limits agricultural crop production. Potato production has fourth rank in the world after rice, wheat, and maize with the production of 321 million tons from 19.6 million hectares. By about 3 percent of cultivation area, potato had 7.2 percent of total agricultural production (5.57 million tons in our country (Iran. Limited studies have been conducted on the interactive effects of Zn and P on potato tubers quality under water deficit conditions. Materials and Methods: This study was conducted for evaluating the effects of soil moisture, phosphorus (P and zinc (Zn levels on the chemical composition and nutrients content of potato (Solanum tuberosum L. cv. Agria as a factorial experiment based on randomized complete blocks design with three factors under greenhouse conditions. The study was performed with factors of Zn at three levels (0, 10 and 20 mg Zn per kg dry soil as ZnSO4.7H2O, P at three levels (0, 30 and 60 mg P per kg dry soil as Ca(H2PO42.H2O (monocalcium phosphate and soil moisture at three levels (0.5FC-0.6FC, 0.7FC-0.8FC and 0.9FC-FC using three replications and 81 pots. The soil moisture levels were imposed three weeks from the flowering (64th day until harvest (85th day after planting. After imposing of soil moisture levels and at the harvest, the yield and yield components, reducing sugars concentration in fresh weight by di- nitro phenol method (Mostofi and Najafi, 2005 and starch by Antron method (Mostofi and Najafi, 2005, N, P, K, Mg, Na, Fe and Zn concentrations in dried potato tubers were measured. Data were subjected to analysis of variance as factorial 3×3×3 with n=3 by using MSTATC software. Duncan's multiple

  9. Potato Starch Residue as a Substrate for Microbial Fermentation%利用微生物发酵马铃薯淀粉渣的研究进展

    雷恒; 曹兵海; 杨富裕; 徐春城


    生物技术的进步为马铃薯淀粉渣等食品工业加工副产品的有效利用提供了新的技术手段.马铃薯淀粉渣是马铃薯淀粉生产过程中产生的主要副产物,因其蛋白质含量较低,纤维素、半纤维素和果胶等含量高,所以作为动物饲料利用时营养价值较低.马铃薯淀粉渣来源丰富,可作为微生物发酵生产诸如酶、蛋白质饲料、有机酸以及膳食纤维等高附加值产品的理想基质.发酵技术用于马铃薯淀粉渣的生物转化备受人们的关注,微生物预处理过程不仅改进了底物的利用,而且能解决废弃物带来的环境污染问题.本文综述了近期通过生物技术手段开发马铃薯淀粉渣的高附加值产品及其工艺的研究进展.%Potato starch residue is the major by-product of the potato starch processing industry. It has low nutritive value because of its low protein content and high amounts of cellulose, hemicelluloses and pectin. Due to the abundant output of by-product, it can be used as an ideal substrate for microbial fermentation to product value-added products such as enzyme preparation, protein-enriched animal feed, organic acid and dietary fiber etc. Application of microbial fermentation technology can be an attractive possibility for such bioconversions. The processing by microbial fermentation has not only improving substrate utilization, but also helping to solve environmental pollution problems. This article reviews the recent research progress on the development of value-added products and techniques of potato starch residue by biotechnological means.

  10. Synthesis of Potato Starch-Acrylic-Acid Hydrogels by Gamma Radiation and Their Application in Dye Adsorption

    Md. Murshed Bhuyan


    Full Text Available Several kinds of acrylic-acid-grafted-starch (starch/AAc hydrogels were prepared at room temperature (27°C by applying 5, 10, 15, 20, and 25 kGy of gamma radiation to 15% AAc aqueous solutions containing 5, 7.5, and 15% of starch. With increment of the radiation dose, gel fraction became higher and attained the maximum (96.5% at 15 kGy, above which the fraction got lowered. On the other hand, the gel fraction monotonically increased with the starch content. Swelling ratios were lower for the starch/AAc hydrogels prepared with higher gamma-ray doses and so with larger starch contents. Significant promotions of the swelling ratios were demonstrated by hydrolysis with NaOH: 13632±10% for 15 kGy radiation-dosed [5% starch/15% AAc] hydrogel, while the maximum swelling ratio was ~200% for those without the treatment. The authors further investigated the availability of the starch/AAc hydrogel as an adsorbent recovering dye waste from the industrial effluents by adopting methylene blue as a model material; the hydrogels showed high dye-capturing coefficients which increase with the starch ratio. The optimum dye adsorption was found to be 576 mg per g of the hydrogel having 7.5 starch and 15% AAc composition. Two kinetic models, (i pseudo-first-order and (ii pseudo-second-order kinetic models, were applied to test the experimental data. The latter provided the best correlation of the experimental data compared to the pseudo-first-order model.

  11. Potato Production, Usage, and Nutrition--A Review.

    Zaheer, Khalid; Akhtar, M Humayoun


    Potato is an economically important staple crop prevailing all across the world with successful large-scale production, consumption, and affordability with easy availability in the open market. Potatoes provide basic nutrients such as-carbohydrates, dietary fiber (skin), several vitamins, and minerals (e.g., potassium, magnesium, iron). On occasion exposures to raw and cooked potatoes impart allergic reactions. Dietary intake of potatoes, especially colored potatoes, play an important role in the production of antioxidant defense system by providing essential nutrient antioxidants, such as vitamins, β-carotene, polyphenols, and minerals. This may help lower the incidence of wide range of chronic and acute disease processes (like hypertension, heart diseases, cancer, neurodegenerative, and other diseases). However, retention of nutrients in potatoes is affected by various cooking and processing methods. Cooking at elevated temperature also produces acrylamide-a suspected carcinogen. Independent and/or collaborative studies have been conducted and reported on the various pathways leading to the formation of acrylamide in heat processed foods. This article reviews the latest research on potato production, consumption, nature of phytochemicals and their health benefits, and allergic reactions to children. Also included is the discovery of acrylamide in processed starch-rich foods including potatoes, mechanism of formation, detection methodologies, and mitigation steps to reduce acrylamide content in food.

  12. Quality of potatoes grown in various regions of Serbia as influenced by heavy metal and pesticide residues concentrations

    Rajković Miloš B.


    Full Text Available It is possible to decompose starch into monosaccharides by the method of acid starch hydrolysis. By applying appropriate chemical procedure, a main solution is obtained, from which aliquots are taken after filtration to determine of the present glucose according to Luff-Shoorlu method. The analysed potatoes of cv. Desiree, grown on various sites in Serbia, have starch content that corresponds to available literature data. The highest starch content is found in potatoes from Ivanjica and Novi Pazar, i.e. from the areas where climate factors, air temperature, and land relief are favourable for potato growing. Lower starch contents are found in potatoes grown in flat areas with warmer climate and drier periods. Those are sites in PKB-Belgrade, Smederevo, Dobanovci and Mrčajevci areas, where the values obtained by experimental procedure are very similar. The lowest starch content is found in potatoes from Belegiš and Guča sites, where starch content is lower than normal from literature values, which may be explained by some special causes (climate, location, irrigation. On the basis of heavy metal contents in potato samples, it may be concluded that potatoes originating from sites famous for potato production are contaminated with Cd the content of which exceeds concentrations permitted by regulations. The presence of Cd in potato samples may also be explained by the application of phosphate fertilizers in higher (or recommended rates. However, the soil itself should also be investigated, especially concerning the content of Cd and pH value. Thus, the influence of the soil itself should be established compared to fertilizer application in the current season. Presence of Cd in potatoes, on the other hand, is highly unfavourable because it prevents its utilization in nutrition, but also as a raw material for further processing of products based on potatoes: chips, etc. Also, Cd presence in foods is strictly controlled by EU, which prevents possible

  13. The role of N1 domain on the activity, stability, substrate specificity and raw starch binding of amylopullulanase of the extreme thermophile Geobacillus thermoleovorans.

    Nisha, M; Satyanarayana, T


    In order to understand the role of N1 domain (1-257 aa) in the amylopullulanase (gt-apu) of the extremely thermophilic bacterium Geobacillus thermoleovorans NP33, N1 deletion construct (gt-apuΔN) has been generated and expressed in Escherichia coli. The truncated amylopullulanase (gt-apuΔN) exhibits similar pH and temperature optima like gt-apu, but enhanced thermostability. The gt-apuΔN has greater hydrolytic action and specific activity on pullulan than gt-apu. The k cat (starch and pullulan) and K m (starch) values of gt-apuΔN increased, while K m (pullulan) decreased. The enzyme upon N1 deletion hydrolyzed maltotetraose as the smallest substrate in contrast to maltopentaose of gt-apu. The role of N1 domain of gt-apu in raw starch binding has been confirmed, for the first time, based on deletion and Langmuir-Hinshelwood kinetics. Furthermore, N1 domain appears to exert a negative influence on the thermostability of gt-apu because N1 truncation significantly improves thermostability.

  14. 马铃薯淀粉废水中蛋白质的提取研究%Research of protein extracting from potato starch waster-water

    任琼琼; 陈丽清; 韩佳冬; 张宇昊; 马良


    The potato protein from starch producing waste-water was extracted by alkali-solution and acid- isolation combined with ultra-filtration. The extraction processing was optimized by single factors and response surface analysis. The results showed that the optimum conditions of extraction processing of protein from potato starch waste-water by alkali-solution and acid-isolation were as follow:the alkali-solution pH9.35, alkali-solution time 59min,acid-isolation pH3.41,acid-isolation time 10min. Under these conditions,the extraction rate of protein reached 54.24%. While combined with ultra-filtration,the extraction rate of protein reached 93.42%.%实验采用碱提酸沉法与超滤相结合从马铃薯淀粉废水中提取蛋白质。通过单因素实验和响应曲面法优化碱提酸沉工艺,结果表明,碱提酸沉法提取马铃薯淀粉废水蛋白质的最佳工艺参数为:碱提pH9.35,碱提时间59min,酸沉pH3.41,酸沉时间10min。在此条件下蛋白质提取率可达54.24%。酸沉液采用10ku超滤膜进一步提取蛋白.最终总提‘取率可达93.42%。

  15. 马铃薯淀粉在冰淇淋生产中的应用%Application of Potato Starch in Ice Cream

    宋春春; 张薇; 魏春光; 王大为


    Potato starch was used as a partial substitute for gelatin and sodium carboxymethyl-cellulose (CMC-Na) to produce ice cream. Its effect on overrun, melting rate and sensory quality was investigated. Using one-factor-at-a-time and orthogonal array design methods, the optimal formulation of ice cream was determined as follows: 4% potato starch, 0.1% CMC-Na, 0.3% monoglyceride and no gelatin. The final product was homogeneous, tasted smooth and delicate and had desired overrun and melting resistance.%用马铃薯淀粉取代明胶和羧甲基纤维素钠(CMC-Na)生产冰淇淋。以冰淇淋的膨胀率、融化率和感官评分为考察指标,研究马铃薯淀粉对冰淇淋品质的影响。通过单因素试验及正交试验确定马铃薯淀粉在冰淇淋生产中最佳用量。结果表明:当马铃薯淀粉添加量4%、CMC—Na添加量0.1%、单甘酯添加量0.3%、不添加明胶时,生产的冰淇淋组织状态均匀一致,口感柔滑细腻,具有理想的膨胀率和适当的抗融性。

  16. Halotolerant, acid-alkali stable, chelator resistant and raw starch digesting α-amylase from a marine bacterium Bacillus subtilis S8-18.

    Kalpana, Balu Jancy; Pandian, Shunmugiah Karutha


    A halotolerant α-amylase having the ability of digesting the insoluble raw starches was characterized from Bacillus subtilis S8-18, a marine sediment isolate from Palk Bay region. The electrophoresis techniques unveiled that the α-amylase was indeed a monomer with a molecular weight of 57 kDa. The optimum temperature and pH for the enzyme activity were 60 °C and 6.0 respectively. The enzyme was highly stable for 24 h over a wide range of pH from 4.0 to 12.0 by showing 84-94% activity. Interestingly, by retaining 72% activity even after 24 h, the enzyme also showed tolerance towards 28% NaCl. The α-amylase retained a minimum of 93% residual activity in 1 mM concentration for the selected divalent metal ions. The enzyme was found to be chelator resistant as it remained unaffected by 1 mM of EDTA and exhibited 96% activity even at 5 mM concentration. Furthermore, though 1% SDS caused remarkable reduction (68%) in amylase activity, the enzyme showed tolerance towards other detergents (1% of Triton-X and Tween 80) with 85% activity. Additionally, the α-amylase enzyme is capable of hydrolyzing the insoluble raw starch substrates which was evident from the scanning electron microscopic (SEM) and spectrophotometric analyses.

  17. Tartary buckwheat (Fagopyrum tataricum Gaertn.) starch, a side product in functional food production, as a potential source of retrograded starch.

    Gao, Jinfeng; Kreft, Ivan; Chao, Guimei; Wang, Ying; Liu, Xiaojin; Wang, Li; Wang, Pengke; Gao, Xiaoli; Feng, Baili


    A starch rich fraction is a side product in Tartary buckwheat processing. This study investigated the fractions that are of technological and nutritional interest. Tartary buckwheat starch granules had a diameter of 3-14 μm, and presented a typical type "A" X-ray diffraction pattern. They contained nearly 39.0% amylose. The solubility of Tartary buckwheat starch was much lower at 70-90 °C (ranging within 9.9-10.4% at 90 °C) than that in maize (up to 49.3%) and potato (up to 85.0%) starch. The starch of one variety of Tartary buckwheat had significantly lower solubility at 70 °C and 80 °C than that of common buckwheat. The starch peak viscosity and breakdown were higher and pasting time was shorter in Tartary buckwheat than in that of the starch of common buckwheat. Tartary buckwheat starch had unique pasting and physicochemical properties, and is thereby capable of being exploited as a suitable raw material of retrograded starch in food processing.

  18. Production and characterization of bio plastics from potato starch, poly-hydroxybutyrate and poly-hydroxybutyrate-co-valerate;Producao e caracterizacao de bioplasticos a partir de amido de batata, poli-hidroxibutirato e poli-hidroxibutirato-co-valerato

    Mendes, Fernanda M.; Curvelo, Antonio A.S., E-mail: fernanda@iqsc.usp.b [Universidade de Sao Paulo (IQ/USP), Sao Carlos, SP (Brazil). Inst. de Quimica


    This work describes the study of thermoplastic starch (TPS) blends obtained from potato starch (plasticised with glycerol) with biodegradable polymers poly-hydroxybutyrate (PHB) and poly-hydroxybutyrate-co-valerate (PHB V). For this purpose it were developed several formulations with TPS/PHB, TPS/PHB V and TPS/PHB/PHB V prepared by physical mixing and water and glycerol as plasticizers. The amount of glycerol was 30% based on starch (dry basis). The starting materials (starch, PHB and PHB V) were characterized by scanning electron microscopy and X-ray diffraction. Then, it was determined the optimal processing conditions for the samples, performed by using an intensive mixer. The materials were hot pressed to produce the standardized samples employed in the characterizations: mechanical testing (tensile strength), dynamic-mechanical thermal analysis (DMTA), scanning electron microscopy and X-ray diffractometry. (author)

  19. Starch Granule Variability in Wild Solanum Species

    Because most of the dry matter of potato tubers is starch, an understanding of starch properties is important in potato improvement programs. Starch granule size is considered to influence tuber processing quality parameters such as gelatinization temperature, viscosity, and water holding capacity. ...

  20. Contents and Viscosity Properties of Extracted Starches from Different Parts of Fresh Sweet Potato Tubers%甘薯不同部位淀粉的组成及黏度特性研究

    贾延宇; 师玉忠; 田丰贺; 张宝宝; 靳卫娜


    The distribution of starches in sweet potato (Ipomoea batatas L. ) tuber was studied. A fresh sweet potato tuber was cut into six equivalent parts, and then the extraction contents and viscosity properties of starches from different parts were determined. The results showed that the extraction content of starch from the middle section of sweet potato was lower than that from the head and the end section, and the extraction content from the inner layer was higher than that from the outer layer. The extraction contents of starch from the inner-end part and the outer-middle part of sweet potato were 16. 2% and 10. 3%, respectively. The amylose content was relatively higher in the middle section and outer layer of sweet potato tubers. The amylose contents in the outer-middle part and the inner-end part of sweet potato tubers were 29. 5% and 26. 7% respectively. The viscosity properties of starches from different parts of sweet potato tubers were different from each other. The peak viscosity and final viscosity of the starch from the head and the end sections were similar and obviously higher than the middle section, and those from the inner layer were higher than the outer layer. The composition and viscosity characteristics of starch were significantly different among different parts of sweet potato, and sweet potato starch with different characteristics and use could be produced by taking sub-site precision machining method.%为了研究甘薯块根中淀粉的分布规律,将鲜甘薯切分成质量相近的6个部位,测定了不同部位的淀粉含量、淀粉中直链淀粉含量以及淀粉黏度特性.结果显示:鲜甘薯中淀粉含量的分布特点是:尾段>头段>中段,内层>外层,尾内部位的淀粉提取量达到16.2%,中外部位的淀粉提取量为10.3%;直链淀粉含量的分布特点是:中段>头段>尾段,外层>内层,中外部位淀粉中,直链淀粉含量达到29.5%,尾内为26.7%;头尾两段中淀粉的峰值

  1. Research on the Process Paraneter of Potato starch Producing Dextrin%马铃薯淀粉生产糊精的工艺参数研究

    姚妙爱; 周玉东


    [目的]对以马铃薯淀粉为原料生产白糊精和黄糊精的工艺参数进行研究,为生产提供参数指导.[方法]通过单因素和L9(34)正交试验,结合生产实际,确定以马铃薯淀粉为原料生产白糊精、黄糊精的最佳参数.[结果]通过试验得出生产白糊精最佳工艺参数为酸用量与淀粉量之比0.20、温度120℃、时间2h、体系含水量23%.生产黄糊精的最佳参数为酸用量与淀粉量之比0.25、温度140℃、时间2h、体系含水量20%.[结论]该试验确定了生产黄糊精与白糊精的最佳工艺参数.%[Objective] The research aimed to study the best processing of use potato starch to produce white and yellow dextrin. [ Method] The processing was optimized by mono-factor and orthogonal experiments. [ Result] The results showed that the optimum reaction condition parameters of producing white dextrin were 0.2 quantity ratio of acid and starch, 23% water content, at 120℃ for 2 h. And the optimum reaction condition parameters of producing yellow dextrin were 0.5 quantity ratio of acid and starch, 20% water content, at 140℃ for 2 h. [ Conclusion] The research established the optimum reaction condition parameters of producing white and yellow dextrin.

  2. Influence of phosphate esters on the annealing properties of starch

    Wischmann, Bente; Muhrbeck, Per


    The effects of annealing on native potato, waxy maize, and phosphorylated waxy maize starches were compared. Phosphorylated waxy maize starch responded to annealing in a manner between that of the naturally phosphorylated potato starch and that of the native waxy maize starch. The gelatinisation ...

  3. Polymeric tannins significantly alter properties and in vitro digestibility of partially gelatinized intact starch granule.

    Amoako, Derrick B; Awika, Joseph M


    Excess calorie intake is a growing global problem. This study investigated effect of complexing partially gelatinized starch with condensed tannins on in vitro starch digestibility. Extracts from tannin and non-tannin sorghum, and cellulose control, were reacted with normal and waxy maize starch in 30% (30E) and 50% ethanol (50E) solutions at 70°C/20min. More tannins complexed with the 30E than 50E starches (mean 6.2 vs 3.5mg/g, respectively). In the 30E treatments, tannins significantly increased crystallinity, pasting temperature, peak viscosity, and slow digesting starch (from 100 to 274mg/g) in normal, but not waxy starch, suggesting intragranular cross-linking with amylose. Tannins doubled resistant starch (RS) to approx. 300mg/g in both starches. In 50E treatments, tannins made both maize starches behave like raw potato starch (>90% RS), suggesting granule surface interactions dominated. Non-tannin treatments generally behaved similar to cellulose. Condensed tannins could be used to favorably alter starch digestion profile.

  4. 瓜尔胶和黄原胶对马铃薯淀粉及其变性淀粉糊化和流变性质的影响%Effects of Guar Gum and Xanthan Gum on Pasting and Rheological Properties of Native and Modified Potato Starch

    蔡旭冉; 顾正彪; 洪雁; 张雅媛; 朱玲


    In this study,pasting and rheological properties of native potato starch,potato starch phosphate ester and cationic potato starch were determined in the respective presence and simultaneous absence of guar gum and xanthan gum.The results indicated that the presence of guar gum enhanced the peak viscosity and pasting temperature of all three kinds of potato starches and deteriorated the thermal stability of starch pastes.The peak viscosities of native potato starch and potato starch phosphate ester rose and the thermal stability and pasting temperature declined due to the presence of xanthan gum,compared to opposite changes observed for cationic potato starch.Dynamic rheological studies revealed that the addition of xanthan gum considerably raised the G' and G'' values and declined the tanδvalue of each kind of potato starch.The dynamic rheological properties of cationic potato starch were affected most obviously.By contrast,guar gum had no obvious effect on the dynamic rheological properties of all three kinds of potato starches.In static rheological studies,we found that starch pastes remained pseudo-plastic fluids despite the presence of either guar gum or xanthan gum,with shorted lag ring area and improved stability.Native potato starch and potato starch phosphate ester were more obviously affected than cationic potato starch.Moreover,xanthan gum had more obvious effect than guar gum.Further,our studies demonstrated that gum-starch interactions play a vital role in pasting and rheological properties of gum-starch complexes.%研究瓜尔胶和黄原胶对马铃薯淀粉、马铃薯磷酸酯淀粉和马铃薯阳离子淀粉糊化和流变性质的影响。糊化性质实验表明瓜尔胶增加了3种淀粉的峰值黏度和成糊温度,降低了淀粉糊的热稳定性。黄原胶降低了马铃薯淀粉和马铃薯磷酸酯淀粉的峰值黏度并提高了糊的热稳定性和成糊温度,但对马铃薯阳离子淀粉起相反作用。动态流变实验

  5. Effects of sorghum (Sorghum bicolor (L.) Moench) tannins on alpha-amylase activity and in vitro digestibility of starch in raw and processed flours

    The effect of condensed tannins (CT) on in vitro starch digestibility in cooked, wholegrain sorghum flours and on corn starch was investigated. CT extracts were also tested for their inhibitory effect on alpha-amylases. Rapidly digestible starch, slowly digestible starch, and resistant starch were n...

  6. Study on the Potato Starch Grafting Acrylate Super Absorbent Resin%洋芋淀粉接枝丙烯酸高吸水性树脂的研究



    [目的]为洋芋淀粉的改性开发利用和制备高吸水性保水材料提供工艺依据.[方法]以洋芋淀粉和丙烯酸为原料,接枝制备高吸水性树指.探讨原料配比、丙烯酸中和度、引发剂浓度和反应温度等主要条件对树脂性能的影响,确定最佳反应参数.[结果]洋芋淀粉接枝丙烯酸具有良好的吸水性和保水性.[结论]洋芋淀粉接枝丙烯酸制备高吸水性树脂,工艺简单成本低,材料环保,有广泛的应用前景.%[Objective] The research aimed to provide the technical basis for the modification development and utilization of potato starch and preparing absorbent materials. [ Method J Potato starch and acrylate were used as materials to prepare super absorbent resin by grafting. The effects of main conditions including material proportion, acrylate neutralization degree, initiator concentration and reaction temperature on the resin properties were discussed. The best reaction parameters were confirmed. [ Result] The potato starch grafting acrylate had a higher water ab-sorptiveness and moisture retention. [ Conclusion ] The preparation of potato starch grafting acrylate super absorbent resin had simple technologies , low cost, convenient materials and wide application foreground.

  7. Intestinal transport and fermentation of resistant starch evaluated by the hydrogen breath test

    Olesen, M; Rumessen, J J; Gudmand-Høyer, E


    To study fermentability of different samples of resistant starch (RS), compared to one another and to lactulose, and to study the effect on gastric emptying of addition of RS to test meal. Finally to study if adaptation to RS results in a measurable change in fermentation pattern, (H2/CH4 product...... production). Sources of RS: Raw potato starch (RPS), 58% RS; corn flakes (CF), 5% RS; hylon VII high amylomaize starch, extrusion cooked and cooled (HAS) 30% RS; highly retrograded hylon VII high amylomaize starch (HRA) 89% RS.......To study fermentability of different samples of resistant starch (RS), compared to one another and to lactulose, and to study the effect on gastric emptying of addition of RS to test meal. Finally to study if adaptation to RS results in a measurable change in fermentation pattern, (H2/CH4...

  8. 低温法制备马铃薯淀粉磷酸双酯的工艺研究%Study on Process in Fabricating Phosphodiesterase of Potato Starch at Low Temperature

    刘高梅; 王常青; 王菲


    为了提高马铃薯淀粉磷酸双酯的特性以及降低生产的能耗,研究采用在40℃的低温条件下,以三氯氧磷为交联剂,聚乙二醇(PEG)为催化剂制备马铃薯淀粉磷酸双酯.结果表明,当稳定剂用量为0.1%、三氯氧磷用量为0.05%、pH 10时所制备的马铃薯淀粉磷酸双酯的粘度为3400 cp,酯化度为0.42.%In roder to enhance the quality of Phosphodiesterase (PDE) of potato starch and slow dowm the energy consumption of production, the low temperature -40℃, POCL3 and PEG were used to fabrica PDE of potato starch. The results showed that the viscosity and degree of esterification on PDE of potato starch was 3400 cp and 0.42 respectively under the conditions which adding stabilizer 0.1%, POCL3 0.05% and pH 10.

  9. Evaluation of Colocasia esculenta Starch as an Alternative Tablet Excipient to Maize Starch: Assessment by Preformulation and Formulation Studies

    Kusuma. R; Venkat Reddy. P; Samba Shiva Rao. A


    Starch isolated from Colocasia esculenta plant was studied as an alternative pharmaceutical excipient to maize and potato starch. The Colocasia esculenta starch has been evaluated by series of tests as mentioned in Indian Pharmacopoeia before being used for evaluation. It was tested along with maize and potato starch as an alternative excipient by performing battery of preformulation and formulation tests. The results obtained for Colocasia esculenta starch was comparable with maize starch an...

  10. Selection of High-starch Potato Material under Different Environmental Conditions%结合不同环境条件筛选马铃薯高淀粉材料

    齐海英; 杜珍; 杨春


    通过两年对不同地区种植的78份马铃薯品种(系)淀粉含量的测定和分析,发现环境条件对马铃薯淀粉含量影响较大。在适宜的生态环境下,马铃薯品种(系)的淀粉含量普遍提高,增幅为0~6.2个百分点。据此提出利用不同环境条件筛选马铃薯高淀粉材料的新思路,在增加入选准确率的同时,对所选材料的淀粉含量及其变化范围、受环境影响等情况能够较好的掌握,为田间生产提供指导。%In two-year test and analysis on starch content of 78 potato varieties (clones) planted in different regions, it could be found that environmental conditions had obvious influence on starch content. In favorable ecological environment, starch content of potato varieties (clones) was generally improved, and the range of content was increased from 0 to 6.2 percent point. Therefore, a new idea was proposed that high-starch potato materials could be selected by using different ecological environments. With improving the accuracy of selection, the range of starch content of the materials grown under different environments could be understood, which might be helpful for guiding works in the field,

  11. Solid State Fermentation of a Raw Starch Digesting Alkaline Alpha-Amylase from Bacillus licheniformis RT7PE1 and Its Characteristics

    Romana Tabassum


    Full Text Available The thermodynamic and kinetic properties of solids state raw starch digesting alpha amylase from newly isolated Bacillus licheniformis RT7PE1 strain were studied. The kinetic values Qp, Yp/s, Yp/X, and qp were proved to be best with 15% wheat bran. The molecular weight of purified enzyme was 112 kDa. The apparent Km and Vmax values for starch were 3.4 mg mL−1 and 19.5 IU mg−1 protein, respectively. The optimum temperature and pH for α-amylase were 55°C, 9.8. The half-life of enzyme at 95°C was 17h. The activation and denaturation activation energies were 45.2 and 41.2 kJ mol−1, respectively. Both enthalpies (ΔH∗ and entropies of activation (ΔS∗ for denaturation of α-amylase were lower than those reported for other thermostable α-amylases.

  12. A new raw-starch-digesting α-amylase: production under solid-state fermentation on crude millet and biochemical characterization.

    Maktouf, Sameh; Kamoun, Amel; Moulis, Claire; Remaud-Simeon, Magali; Ghribi, Dhouha; Chaabouni, Semia Ellouz


    A new Bacillus strain degrading starch, named Bacillus sp. UEB-S, was isolated from a southern Tunisian area. Amylase production using solid-state fermentation on millet, an inexpensive and available agro-resource, was investigated. Response surface methodology was applied to establish the relationship between enzyme production and four variables: inoculum size, moisture-to-millet ratio, temperature, and fermentation duration. The maximum enzyme activity recovered was 680 U/g of dry substrate when using 1.38 × 10(9) CFU/g as inoculation level, 5.6:1 (ml/g) as moisture ratio (86%), for 4 days of cultivation at 37 degrees C, which was in perfect agreement with the predicted model value. Amylase was purified by Q-Sepharose anion-exchange and Sephacryl S-200 gel filtration chromatography with a 14-fold increase in specific activity. Its molecular mass was estimated at 130 kDa. The enzyme showed maximal activity at pH 5 and 70 degrees C, and efficiently hydrolyzed starch to yield glucose and maltose as end products. The enzyme proved its efficiency for digesting raw cereal below gelatinization temperature and, hence, its potentiality to be used in industrial processes.

  13. Crystal structure of a raw-starch-degrading bacterial α-amylase belonging to subfamily 37 of the glycoside hydrolase family GH13

    Liu, Yanhong; Yu, Jigang; Li, Fudong; Peng, Hui; Zhang, Xuecheng; Xiao, Yazhong; He, Chao


    Subfamily 37 of the glycoside hydrolase family GH13 was recently established on the basis of the discovery of a novel α-amylase, designated AmyP, from a marine metagenomic library. AmyP exhibits raw-starch-degrading activity and consists of an N-terminal catalytic domain and a C-terminal starch-binding domain. To understand this newest subfamily, we determined the crystal structure of the catalytic domain of AmyP, named AmyPΔSBD, complexed with maltose, and the crystal structure of the E221Q mutant AmyPΔSBD complexed with maltotriose. Glu221 is one of the three conserved catalytic residues, and AmyP is inactivated by the E221Q mutation. Domain B of AmyPΔSBD forms a loop that protrudes from domain A, stabilizes the conformation of the active site and increases the thermostability of the enzyme. A new calcium ion is situated adjacent to the -3 subsite binding loop and may be responsible for the increased thermostability of the enzyme after the addition of calcium. Moreover, Tyr36 participates in both stacking and hydrogen bonding interactions with the sugar motif at subsite -3. This work provides the first insights into the structure of α-amylases belonging to subfamily 37 of GH13 and may contribute to the rational design of α-amylase mutants with enhanced performance in biotechnological applications. PMID:28303907

  14. Efficient production of optically pure D-lactic acid from raw corn starch by using a genetically modified L-lactate dehydrogenase gene-deficient and alpha-amylase-secreting Lactobacillus plantarum strain.

    Okano, Kenji; Zhang, Qiao; Shinkawa, Satoru; Yoshida, Shogo; Tanaka, Tsutomu; Fukuda, Hideki; Kondo, Akihiko


    In order to achieve direct and efficient fermentation of optically pure D-lactic acid from raw corn starch, we constructed L-lactate dehydrogenase gene (ldhL1)-deficient Lactobacillus plantarum and introduced a plasmid encoding Streptococcus bovis 148 alpha-amylase (AmyA). The resulting strain produced only D-lactic acid from glucose and successfully expressed amyA. With the aid of secreting AmyA, direct D-lactic acid fermentation from raw corn starch was accomplished. After 48 h of fermentation, 73.2 g/liter of lactic acid was produced with a high yield (0.85 g per g of consumed sugar) and an optical purity of 99.6%. Moreover, a strain replacing the ldhL1 gene with an amyA-secreting expression cassette was constructed. Using this strain, direct D-lactic acid fermentation from raw corn starch was accomplished in the absence of selective pressure by antibiotics. This is the first report of direct D-lactic acid fermentation from raw starch.

  15. α-淀粉酶和糖化酶协同酶解马铃薯淀粉的工艺条件优化%Study on hydrolysis of potato starch by α-amylase and glucoamylase

    李玉芹; 袁正求; 冯岳; 黎萍; 周蒙; 姚威; 张剑


    【目的】探讨α-淀粉酶和糖化酶协同酶解马铃薯淀粉的工艺条件,为降低微藻生产生物柴油成本提供参考。【方法】采用α-淀粉酶和糖化酶协同酶解马铃薯淀粉,以葡萄糖含量为测定指标,选取反应温度、底物质量浓度、加酶量(m(α-淀粉酶)∶m(糖化酶)=3∶1)、反应时间4个影响因素,进行L25(54)正交试验,确定最佳酶解工艺条件;采用高效液相色谱法(HPLC)、电子扫描电镜(SEM)、X射线衍射(XRD)法对酶解产物的物理特性进行分析。【结果】最佳酶解工艺条件为:反应温度80℃、底物质量浓度0.1 g/mL、加酶量为%【Objective】 The optimal hydrolysis technology of potato starch by α-amylase and glucoamylase was discussed to provide a reference for reducing the costs of biodiesel.【Method】 The enzymatic hydrolysis of potato starch was carried out by α-amylase and glucoamylase.The enzymatic hydrolysis conditions were optimized with L25(54)orthogonal test and the reaction temperature,substrate concentration,enzyme dosag(m(α-amylase)∶m(glucoamylase)=3∶1) and reaction time were chosen as the factors with the yield of the glucose as determination of indicators;the potato starch hydrolysate was subjected to analysis by HPLC,SEM,XRD.【Result】 The results showed that the optimum conditions were as follows:temperature,substrate concentration,the best enzyme dosage,reaction time and pH were 80 ℃,0.1 g/mL,ratio of enzyme dosage to dry starch of 0.6%,4 h and pH 4.0 respectively,and under this condition,the percent of glucose was the highest,which reached 802.9 g/L.The results of HPLC,SEM,XRD showed that the glucose reached the highest proportion in the enzymatic hydrolyzate.The enzymatic hydrolysis did not destroy the crystal structure of potato starch,the enzymatic hydrolysis just occured on the surface of the potato starch.【Conclusion】 The optimal hydrolysis technology of potato

  16. Study on oxidized starch properties of potato and its effect on qualities of Harbin sausage%马铃薯氧化淀粉性质及其对哈尔滨红肠品质的影响

    韩冰; 杜明; 王聪; 徐树来; 叶暾昊; 袁超


    Chlorine peroxide was chosen as oxidant to prepare potato oxidized starch,and the properties of oxidized starch were determined. Subsequently,potato oxidized starch was applied in Harbin sausage to investigate its effect on quality of sausage. The results showed that when 0.15% chlorine dioxide,0.0125% LXF activator,temperature at 35% for 2.5h,potato oxidized starch was prepared. Some properties of oxidized starch were studied, carboxyl content was 0.1862%, carbonyl content was 0.0548%,viscosity was 15.69Pa·s, light transmittance was 19.23%, precipitation was 0.647. From the Scanning electron microscopy(SEM) results, after being oxidized by chlorine dioxide,the surface of potato oxidized starch was cruder and some cracks were found. Moreover,the oxidized starch was investigated with Infrared spectroscopy (IR), hydroxyl content decreased and carboxyl content increased significantly. At last,after potato oxidized starch added in Harbin sausage, results showed that the addition of potato oxidized starch have improved the hardness, elasticity and chewiness significantly.%二氧化氯作为氧化剂制备马铃薯氧化淀粉,然后对其部分性质进行研究,并考察了添加马铃薯氧化淀粉对哈红肠品质的影响。马铃薯氧化淀粉的制备过程中,二氧化氯的添加量0.15%,LXF专用活化剂添加量为0.0125%,反应时间2.5h,反应温度35℃,在此条件下制备的氧化淀粉,其羧基含量0.1862%,羰基含量0.0548%,粘度15.69Pa.s,透光率19.23%,凝沉性0.647。由电镜扫描结果可知,马铃薯原淀粉经ClO2氧化后,淀粉表面变得较为粗糙,出现裂纹。红外光谱分析表明,体系中醇羟基的含量减少,而COO-含量明显增加。将马铃薯氧化淀粉添加到哈尔滨红肠中,通过质构分析发现红肠的硬度、弹性和咀嚼性明显提高。

  17. 超声波处理对马铃薯淀粉热力学性质的影响%Effects of ultrasonic treatment on thermal property of potato starch



    运用差示扫描量仪(DSC)研究了超声波对马铃薯淀粉热力学性质的影响。采用超声波对马铃薯淀粉进行处理,结果表明经过超声波处理,可提高马铃薯淀粉的相变起始温度(To)、糊化焓和回生焓,降低了相变峰值温度(Tp)和相变终止温度(Tc)。以上数据表明,超声波处理在一定程度上破坏了淀粉分子间氢键,使得淀粉分子降解。%Differential scanning calorimetry (DSC) was used to investigate the effects of ul- trasonic treatment on the thermal property of potato starch. Potato starch was treated by ultra- sonic treatment. The results show that ultrasonic treatment increases To, enthalpy of gelatiniza- tion and enthalpy of aging. The Tp and Tc are decreased by this treatment. The data shows that ultrasonic treatment destructs the C- C bonds in starch chain and degrades the starch molecules.

  18. Envejecimiento de Almidones Termoplásticos Agrios de Yuca y Nativos de Papa por Microscopía de Fuerza Atómica Ageing of Sour Cassava and Native Potato Thermoplastic Starches by Atomic Force Microscopy

    Harold A Acosta


    Full Text Available En este trabajo, se determinó la topografía de almidones termoplásticos (TPS agrio de yuca y nativo de papa, mediante microscopía de fuerza atómica (AFM, durante un periodo de 120 días de almacenamiento. Mezclas de almidones agrios (fermentados de yuca y nativo de papa, y glicerina, se procesaron en un extrusor de husillo sencillo. Láminas de TPS agrio de yuca (SCTPS y nativo de papa (NPTPS, se observaron y midieron por AFM (en modo contacto. Sus superficies mostraron incremento en rugosidad y partes lisas solo a altos contenidos de plastificante, pero SCTPS siempre tuvo menor rugosidad que NPTPS, debido a la fermentación natural del almidón agrio. Estos cambios se relacionaron con el tamaño, la forma del gránulo y particularmente con el contenido de plastificante. Los NPTPS de mayor rugosidad presentaron separación de fases a los 120 días, dada la retrogradación de las moléculas del almidón, que tienden a formar cristalitos. Estos resultados indican que el almidón agrio de yuca puede retardar la retrogradación de almidones termoplásticos, lo cual es importante durante el desarrollo de nuevos empaques biodegradables.This study reports on the topography of thermoplastic starches (TPS from sour cassava and native potato using atomic force microscopy (AFM, over a 120 day-storage period. Mixtures of sour cassava (fermented and native potato starches plus glycerine, were processed using a single-screw extruder. Sour cassava thermoplastic starch (SCTPS and native potato thermoplastic starch (NPTPS films were observed and measured by AFM (in contact mode. Their surfaces showed increased rugosity, and smooth parts only at high plasticizer content. However, SCTPS always had lower rugosity than NPTPS, due to the natural fermentation of sour cassava starch. These changes were related to starch granule size and shape, and particularly to plasticizer content. NPTPS with higher rugosity presented phase separation at 120 days, due to

  19. Purification and kinetics of a raw starch-hydrolyzing, thermostable, and neutral glucoamylase of the thermophilic mold Thermomucor indicae-seudaticae.

    Kumar, Sanjeev; Satyanarayana, T


    The purified glucoamylase of the thermophilic mold Thermomucor indicae-seudaticaehad a molecular mass of 42 kDa with a pI of 8.2. It is a glycoprotein with 9-10.5% carbohydrate content, which acted optimally at 60 degrees C and pH 7.0, with a t(1/2) of 12 h at 60 degrees C and 7 h at 80 degrees C. Its experimental activation energy was 43 KJ mol(-1) with temperature quotient (Q(10)) of 1.35, while the values predicted by response surface methodology (RSM) were 43 KJ mol(-1) and 1.28, respectively. The enzyme hydrolyzed soluble starch at 50 degrees C (K(m) 0.50 mg mL(-1) and V(max) 109 micromol mg(-1) protein min(-1)) and at 60 degrees C (K(m) 0.40 and V(max) 143 micromol mg(-1) protein min(-1)). The experimental K(m) and V(max) values are in agreement with the predicted values at 50 degrees C (K(m) 0.45 mg mL(-1) and V(max) 111.11 micromol mg(-1) protein min(-1)) and at 60 degrees C (K(m) 0.36 mg mL(-1)and V(max) 142.85 micromol mg(-1) protein min(-1)). An Arrhenius plot indicated thermal activation up to 60 degrees C, and thereafter, inactivation. The enzyme was strongly stimulated by Co(2+), Fe(2+), Ag(2+), and Ca(2+), slightly stimulated by Cu(2+) and Mg(2+), and inhibited by Hg(2+), Zn(2+), Ni(2+), and Mn(2+). Among additives, dextran and trehalose slightly enhanced the activity. Glucoamylase activity was inhibited by EDTA, beta-mercaptoethanol, dithiothreitol, and n-bromosuccinimide, and n-ethylmaleimide inhibited its activity completely. This suggested the involvement of tryptophan and cysteine in catalytic activity and the critical role of disulfide linkages in maintaining the conformation of the enzyme. The enzyme hydrolyzed around 82% of soluble starch and 65% of raw starch (K(m) 2.4 mg mL(-1), V(max) 50 micromol mg(-1) protein min(-1)), and it was remarkably insensitive to glucose, suggesting its applicability in starch saccharification.

  20. Bioethanol production from sweet potato using Saccharomyces diastaticus

    Abdullah, Suryani, Irma; Pradia Paundradewa, J.


    Sweet potato contains about 16 to 40% dry matter and about 70-90% of the dry matter is a carbohydrate made up of starch, sugar, cellulose, hemicellulose and pectin so suitable for used as raw material for bioethanol. In this study focused on the manufacture of bioethanol with changes in temperature and concentration variations of yeast with sweet potato raw materials used yeast Saccharomyces diastaticus. Operating variables used are at a temperature of 30°C; 31,475°C; 35°C; 38,525°C; and 40°C with a yeast concentration of 25.9%; 30%; 40%; 50% and 54.1%. The experimental results obtained, the optimum conditions of ethanol fermentation with yeast Saccharomyces diastaticus on 36,67 °C temperature and yeast concentration of 43,43 % v / v.

  1. 球磨法微细化马铃薯淀粉工艺优化%Optimization of micronization technology for potato starch with a ball-grinding method

    杨宏志; 刘凤亮


    Objective To investigate the influence of various conditions on the effect of micro-miniaturization of potato starch after food-grade potato starch was micronized with a ball-grinder. Methods With the par-ticle size of potato starch as experimental indexes, the quadratic orthogonal regression experiments were de-signed, and the regressive equations concerning the experimental indexes and experimental parameters were obtained for grinding process. According to the influence of experimental parameters on the particle size of potato starch, the order of parameters is, milling time>rotary speed>mass concentration. The most appropri-ate conditions for the process of micronization of potato starch were obtained according to the results of a series of grinding experiments carried out with ball-grinder. Results The conditions mentioned above were milling time 24 h, rotary speed 350 r/min and mass concentration 0.35 g/mL, respectively. Conclusion Quadratic regression orthogonal rotation combination test results showed that the main impact of the order of potato starch miniaturization process factors were: the milling time, ball speed and starch concentration; starch grain size under optimal conditions for 11.019μm, return model predicted deviation was 2.7%with a higher prediction accuracy.%目的:利用球磨设备对普通食用级马铃薯淀粉进行微细化加工,研究不同微细化条件对马铃薯淀粉微细化效果的影响。方法采用二次正交旋转回归试验对微细化工艺进行优化,通过得到的二次正交旋转回归方程,确定影响微细化结果的各因素的主次顺序依次为:球磨时间、球磨机转速、淀粉液浓度。结果经试验最后确定马铃薯淀粉微细化的最适宜条件为以无水乙醇为球磨介质,球磨时间24 h,球磨机转速350 r/min,淀粉液浓度0.35 g/mL。结论二次正交回归旋转组合试验结果表明,影响马铃薯淀粉微细化工艺的各因素的主次顺序依次为:球

  2. Determination of Phosphorylated Oligosaccharides Prepared from Potato Starch%a马铃薯淀粉制得磷酸寡糖的定性定量测定

    杨丽; 杨文军; 刘霞; 杜先锋


    The current study was carried out to quantitatively and qualitatively analyze phosphorylated sligosaccharides prepared from potato starch by totally enzymatic method. The phosphorylated sligosaccharide composition was determined by thin layer chromatography (TLC) and high performance anionic exchange chromatography with pulsed amperometric detection (HPAEC-PAD). Infrared spectroscopy (IR) was used for structure elucidation. The analytes were identified as a mixture of maltooligosaccharides containing phosphate groups and having a degree of polymerization between 3 and 7, in which maltotriose, maltotetraose, maltopentaose and maltohexaose were the dominant components.%对以马铃薯淀粉为原料、全酶法制得的磷酸寡糖进行定性定量分析。通过采用薄层层析法(thin layer chromatography,TLC)和高效阴离子交换色谱.脉冲安培检测(high-performance anionic exchange chromatography—air pulsing ampere detectors,HPAEC-PAD)对磷酸寡糖组分进行检测分析,同时利用红外吸收光谱(infraredspectreoscopy,IR)对其进行结构分析。结果表明:磷酸寡糖是结合有磷酸基团的并且

  3. 甘薯交联抗性淀粉热力学性质与消化性研究%Thermodynamic properties and digestibility of sweet potato cross-linked resistant starches

    李云云; 高群玉


      The thermodynamic properties of sweet potato cross–linked resistant starches and native starch were analysed synthetically based on swelling power,degrees of gelatinization and thermodynamic parameters measured by differential scanning calorimetry(DSC). In–vitro model proposed by Jenkins was investigated the digestion of starch. Results showed that swelling power, degrees of gelatinization of sweet potato cross–linked resistant starches were lower than native starch at the same temperature,and the higher dosage the crosslinking agent was,the smaller swelling power and degrees of gelatinization of starch were. The phase inversion temperature To,Tp and Tc of cross–linked resistant starch rose with increasing crosslinking agent dasage. In–vitro digestion test showed that digestibility of all the cross–linked resistant starches were lower than native starch. The total carbohydrate digestion products and the average rate of digestion of resistantstarches were decreased with increasing crosslinking agent dasage.%  根据膨胀度、糊化度及差示扫描量热仪(DSC)测得热力学参数,综合分析甘薯交联抗性淀粉和原淀粉热力学性质,并采用Jenkins提出In–vitro模型测定淀粉体外消化性.结果表明:在同一温度下,甘薯交联抗性淀粉膨胀度和糊化度均较原淀粉低,且交联剂用量越高,淀粉膨胀度和糊化度越小;DSC测试结果显示,甘薯交联抗性淀粉相转变温度To、Tp、Tc随交联剂用量增加而升高,Tc–To和△H均比原淀粉低.In–vitro消化模拟实验表明,甘薯交联抗性淀粉消化性比原淀粉低,并随交联剂含量增加,消化产物量减少,消化速度降低.

  4. Study on the preparation of crosslinking potato starch using microwave radiation%微波法合成交联马铃薯淀粉的工艺研究

    陆来仙; 石海信; 李雪妹; 刘松; 梁活玲


    Crosslinking Potato Starch (CPS) was prepared by potato starch and sodium trimetaphosphate (STMP) under microwave radiation. The effects of action time of microwave, pH, concentration of starch, amount of ST on the combined phosphorus (CP) were studied by single factor experiments and orthogonal experiments. The CPS with a CP of 0.0305% was obtained in the conditions of concentration of starch 30% (mass fraction), amount of STMP to the content of starch 0.3% , pH 10.0 and action time of microwave 4 min. Furthermore, the granular morphology and functional groups were characterized by SEM and FTIR, respectively. The results showed that the surface of starch was eroded by reaction of crosslinking and some deboss were found. Meanwhile, the peak at 1050 ~970cm‐1 related to P = O was strengthened. All these proved that the reaction of crosslinking between potato starch and STMP was succeeded.%以马铃薯淀粉为原料,三偏磷酸钠为交联剂,在微波辐射条件下制备交联淀粉.以结合磷为评价指标,探讨了微波加热时间、pH、淀粉质量分数和三偏磷酸钠的用量四个因素对交联马铃薯淀粉交联度的影响.通过单因素和正交试验,获得微波法制备交联马铃薯淀粉的较佳工艺参数为:马铃薯淀粉质量分数为30%,三偏磷酸钠用量为淀粉质量(干基)的0.3%,反应pH 10,时间4min.在此条件下制得结合磷含量为0.0305%的交联马铃薯淀粉.分别采用扫描电镜和红外光谱仪对产品结构进行表征.扫描电镜显示淀粉颗粒表面受到侵蚀,部分颗粒出现凹陷,红外光谱图显示在1050~970cm-1处P=O吸收峰加强,证明淀粉确实发生了交联反应.

  5. Use of mesophilic fungal amylases produced by solid-state fermentation in the cold hydrolysis of raw babassu cake starch.

    de Castro, Aline Machado; de Andréa, Thiago Vetter; Castilho, Leda dos Reis; Freire, Denise Maria Guimarães


    Amylases constitute one of the most important groups of industrial enzymes, presenting several applications, such as in the food, textile, and ethanol manufacturing. In this work, a starchy residue from the Brazilian agroindustry, namely babassu cake, was used for the production of amylases by solid-state fermentation and for obtaining sugar hydrolysates, which can be used as building blocks for future bioconversions. Eight filamentous fungi from the genera Aspergillus and Penicillium were screened. Regarding amylase production, A. awamori strains showed well-balanced endoamylase and exoamylase activities, while A. wentii produced an amylolytic complex much richer in the endo-acting enzymes. Simultaneous liquefaction and saccharification using the crude enzyme extracts from the four most promising fungal strains was then investigated applying DOE techniques. The highest total reducing sugar content (24.70 g L(-1)) was obtained by the crude extract from A. awamori IOC-3914, corresponding to a hydrolysis yield of 52% of total starch in the cake, while A. awamori IOC-3915 produced the most appropriate extract in terms of glucose release (maximum of 5.52 g L(-1)). Multivariate analysis of the DOE studies indicated that these extracts showed their best performance at 50-57 degrees C under acid conditions (pH 3.6-4.5), but were also able to act satisfactorily under milder conditions (36 degrees C and pH 5.0), when TRS and glucose released were about 65% of the maximum values obtained. These data confirm the high potential of the enzyme extracts under study for cold hydrolysis of starch.

  6. Influence of potato starches on functional properties of common carp myofibrillar protein%马铃薯淀粉对鲤鱼肌原纤维蛋白功能特性的影响

    杨明; 孔保华; 董和亮; 夏秀芳; 丁一; 王松; 黄莉


    将马铃薯淀粉(不同添加量0%、1%、2%、3%和4%)添加到鲤鱼肌原纤维蛋白中,通过测定肌原纤维蛋白的浊度、乳化性、凝胶的硬度、弹性、保水性、白度值等指标,较为系统地研究了马铃薯淀粉对鲤鱼肌原纤维蛋白功能特性的影响.结果表明:在温度一定时,淀粉-蛋白复合物的浊度随着马铃薯淀粉添加量的增大而升高;在马铃薯淀粉添加量一定时,淀粉-蛋白复合物的浊度随着温度的升高而升高.随着马铃薯淀粉添加量的增加,乳化活力和乳化稳定性呈先上升后下降后又有所增加的趋势,在马铃薯淀粉添加量为2%和1%时乳化活性和乳化稳定性分别达到最大值25.66m2/g,90.67%.当温度相同时,淀粉-蛋白复合凝胶的硬度和弹性值随着马铃薯淀粉添加量的增大而升高,在80℃条件下,添加了4%淀粉的样品与对照组相比硬度和弹性分别提高了65.85%,20.85%,且效果显著(p<0.05),而随着马铃薯淀粉添加量的增加,凝胶持水性增大(p<0.05),最大增加了18.75%,但凝胶的白度值呈现下降趋势.因此添加马铃薯淀粉可以有效改善肌原纤维蛋白的功能特性.%The effects of potato starches(0% 、1% 、2% 、3% 、4%) on the functional properties of common carp myofibrillar protein were studied.Turbidity,emulsifying propertity of myofibrillar protein and hardness,springiness,whiteness,water-holding capacity myofibrillar protein gelation were evaluated.Results indicated under the same temperature,turbidity increased with the potato starches content increased from 1% to 4%.Under the same potato starches content,turbidity increased with the temperature increased.EAI and ESI of MPI increased then decreased and increased again as the increased of potato starches content.EAI and ESI reached maximum 25.66m2/g and 90.67% by adding 2% potato starches and 1% potato starches.Under the same temperature,starch

  7. 浙贝母和平贝母中淀粉的结晶学、形态学和热性质研究及与马铃薯淀粉的比较%Crystallography, morphology, and thermal properties of starch in Fritillaria thunbergii and F. ussurensis as well as comparison with potato starch

    王书军; 高文远; 贾伟; 肖培根


    Objective To fully understand the medicinal plants of Fritillaria L. , the physicochemical properties of starch in two species of Fritillaria L. , F. thunbergii and F. ussurensis. were investigated by means of various analytical methods. Methods The properties of starch in the two different species of Fritillaria L. were compared by X-ray diffraction, scanning electron microscope (SEM) and themogravimetric analysis (TGA). Results The crystal type of starch in the two species of Fritillaria L.was the characteristic B-type which was in consistent with that of potato starch. The degrees of crystallinity of F. thunbergii starch and F. ussurensis starch were about 29.9% and 20.1%, respectively. However,the degree of crystallinity of the potato starch was 44.9%. From the crystallinity degree of the starch in two species of Fritillaria L. , it could be concluded that the content of amylose in F. ussurensis starch was higher than that in F. thunbergii starch. The granule size of the starch in two species of Fritillaria L.ranged from 5 to 40 μm, which were all smaller than that of the potato. The starch granule in two species of Fritillaria L. was in cycloidal or elliptic-shape. It could be concluded that the thermal stability of the starch in two species of Fritillaria L. was different due to the different structures of different starch in various plants by TGA. Conclusion The physicochemical properties of starch in two different species of Fritillaria L. differ a lot due to their geographical origin.%目的为了能够更加充分了解贝母属药用植物,通过各种分析方法对两种贝母--浙贝母和平贝母中所包含的淀粉的物理化学性质进行了研究.方法采用X射线衍射,扫描电子显微镜(SEM)以及热分析(TGA)的方法对两种贝母中淀粉的性质进行了比较.结果通过研究发现,两种贝母淀粉的晶体类型都为典型的B型,这与马铃薯淀粉的晶体类型是一致的.浙贝母和平贝母

  8. Influência da adição da fécula de batata-doce (Ipomoea batatas L. sobre a viscosidade do permeado de soro de queijo Influence of sweet potato starch at permeate whey viscosity

    Rafael Leite Pinto de Andrade


    Full Text Available A viscosidade é um parâmetro importante na aceitabilidade de bebidas lácteas. O presente trabalho teve como objetivo principal fornecer dados relativos ao comportamento da viscosidade uma base de permeado de soro de queijo adicionada de fécula de batata-doce, dados que poderão ser utilizados na elaboração de uma nova bebida láctea. A fécula de batata-doce utilizada apresentou um grau de gelatinização de 72,64%, umidade média de 7,88% e a seguinte composição centesimal média em base seca: 82,59% de amido, 9,33% de fibras dietéticas totais, 4,90% de proteínas, 2,08% de cinzas e 1,11% de lipídios. O permeado de soro foi adicionado a três diferentes concentrações de fécula e submetido a diferentes tratamentos térmicos. A viscosidade mais adequada, em função dos dados obtidos junto aos produtos comerciais, estaria no intervalo de 45mPa.s a 70mPa.s. Assim sendo, a porcentagem de 6% de fécula de batata-doce e um tratamento térmico de 90ºC por cerca de 5 minutos mostrou-se ser o mais adequado. O fluido obtido apresentou um comportamento pseudoplástico.Viscosity is an important parameter of milky drinks acceptability. This work supply data of the viscosity properties of permeate whey plus sweet potato starch basis; these data will may be used at development of a new milky beverage. The used sweet potato starch presented 72.64% of gelatinization, 7.88% of humidity and the following dry composition: 82.59% starch, 9.33% total dietary fibres, 4.90% proteins, 2.08% ashes and 1.10% lipids. The permeate whey had mixed at three different percentages of potato starch and had submitted at various thermal treatments. The most appropriate viscosity, in accord of commercial products, it would be in the interval of 45mPa.s to 70mPa.s. Therefore, the percentage of 6% of sweet potato starch and a thermal treatment of 90ºC for about 5 minutes it was shown to be the most appropriate. The fluid presented a pseudoplastic properties.

  9. Degradation of Raw Corn Starch by an α-Amylase (AmyP) from Marine Environment%海洋环境来源的淀粉酶AmyP对生玉米淀粉的降解特性

    彭惠; 雷寅; 刘源涛; 汪颖


    来自海洋宏基因组文库的α-淀粉酶(AmyP)属于最新建立的糖苷水解酶亚家族GH13_37.AmyP是一个生淀粉降解酶,能有效降解玉米生淀粉.在最适反应条件pH7.5和40℃下,生玉米淀粉的比活达到(39.6±1.4) U/mg.酶解反应动力学显示AmyP可以非常快速的降解生玉米淀粉.对1%的生玉米淀粉降解仅需要30min;4%和8%的生玉米淀粉只需3h.DTT可以显著提高AmyP对生玉米淀粉的降解活性,1% DTT促使活性增加1倍.根据电镜观察和产物分析,认为AmyP是以内腐蚀的模式降解生玉米淀粉颗粒,释放出葡萄糖、麦芽糖和麦芽三糖作为终产物.%The α-amylase ( AmyP) from a marine metagenomic library belongs to the recently classified glycoside hydrolase subfamily GH13_37. AmyP is raw starch degrading enzyme, exhibiting a remarkable ability to digest raw corn starch. The specific activity of raw corn starch was reached (39. 6 ± 1.4) U/mg under the optimum pH 7. 5 and temperature 40 ℃. The hydrolysis curve showed that AmyP could hydrolyze raw corn starch at a very high speed. The final hydrolysis degrees were obtained in 30min for 1% raw corn starch and 3h for 4% and 8% concentration. The enzyme's activity was greatly increased in the presence of DTT. 1% DTT led to a twofold-enhanced activity. The results of scanning electron microscopy and thin-layer chromatography show that AmyP attacks sites on raw corn starch granules with a mode of endo-corrosion, and releases glucose, maltose and maltotriose as end products.

  10. Study on the synergistic effect between KGM and potato starch blend gels%魔芋葡甘聚糖与马铃薯淀粉相互协同作用研究



    该文选用KGM为亲水胶体,考察对马铃薯淀粉糊化、流变特性及冻融稳定性的影响,通过对主要参数的统计学分析,探讨其变化规律。淀粉的糊化特性分析结果发现,与单独淀粉体系相比,加入KGM后,复配体系的峰值黏度随着亲水胶体比例的增大而显著增加,而糊化温度降低。KGM的加入能在一定程度上抑制马铃薯淀粉的回生,提高淀粉糊的冷稳定性。动态流变特性分析发现所有样品的贮能模量G'>损耗模量G'',损耗角正切值(tanδ=G"/G')均<1,表现为一种典型的弱凝胶动态流变学谱图。静态流变特性分析结果表明,不同配比的KGM与淀粉复配体系均表现出剪切变稀的现象,即为假塑性流体的性质。同时,Power–law方程适用于本试验样品体系流变曲线的拟合,相关系数均在0.90以上。对复合体系的冻融稳定性考察还发现KGM与马铃薯淀粉复配体系冻融稳定性好适合于加工冷冻食品。%In this study,KGM was selected as hydrophilic colloid,and the influence of KGM on gelatinization,rheological properties and freeze–thaw stability of potato starch was investigated. The result of starch gelatinization characteristics analysis showed that,compared with the single starch system,the peak viscosity of the combined systems increased with the increasing percentage of hydrophilic colloid significantly,but the gelatinization temperature down. The addition of KGM can restrain the retrogradation of potato starch in some certain extent,and increased the cold stability of starch paste. Dynamic rheological properties analysis exhibited that storage modulus G' was higher than loss modulus G"and loss tangent(tanδ=G"/G')was lower than 1 for all measured samples, which indicated all measured samples exhibited as a kind of typical dynamic rheological weak gel chromatogram. The rheological properties of the static analysis showed that different ratio of

  11. Structural studies on methylated starch granules

    Vliegenthart, J.F.G.; Burgt, Y.E.M. van der; Bergsma, J.; Bleeker, I.P.; Mijland, P.J.H.C.; Kamerling, J.P.


    Granules of potato starch and amylopectin potato starch were methylated in aqueous alkaline suspension. Here, an overview is given of all structural aspects that have been studied with respect to the determination of the location of the substituents. Methods, which are generally applicable, were

  12. Synthesis, analysis and reduction of 2-nitropropyl starch

    Heeres, A; van Doren, HA; Gotlieb, KF; Bleeker, IP; Kellogg, RM; Doren, Henk A. van; Gotlieb, Kees F.; Bleeker, Ido P.


    Granular 3-nitropropyl potato starch was synthesized by reaction with 3-nitropropyl acetate in an aqueous suspension. Nitroalkylation occurs preferentially with the amylose fraction of potato starch, as was confirmed by leaching experiments and digestion of the modified starch with alpha -amylase. T

  13. Performance of enzyme transformed raw starch as surface sizing agent%改善酶转化玉米原淀粉的表面施胶胶料使用性能

    危志斌; 张瑞杰


      淀粉酶连续转化玉米原淀粉能大幅降低表面施胶胶料成本达到降低纸产品成本的目的,但同时需要改善表面施胶胶料的使用性能,否则可能影响施胶效果和产品质量。太阳纸业天章#19机使用淀粉酶连续转化木薯原淀粉和玉米原淀粉代替阳离子氧化生淀粉,通过提高原淀粉的质量、提高活化温度和储存温度等措施成功地改善了表面施胶胶料的使用性能,保证了施胶效果和产品质量。%Transforming corn starch continuously with starch enzyme can reduce the cost of paper products by dramatically reducing surface sizing cost, at the same time the surface siz-ing liquid performance need to be improved, otherwise it may affect the sizing effect and paper quality. Raw cassava and corn starch continuously transformed with starch enzyme were ap-plied in Tianzhang PM19, Sun Paper, in place of cationic oxi-dized starch. The performance of the surface sizing liquid was improved by raising raw starch quality and raising the activation temperature and storage temperature, to ensure the sizing effect and paper quality.

  14. Effect of Four Kinds of Food Additives on Retrogradation of Potato Starch%四种食品添加剂对马铃薯淀粉老化性的影响

    岳晓霞; 王梁; 张根生; 侯静; 孙丹丹


    Study the effect of glycerin monostearate, carboxymethylcellulose, guar gum,β-cyclodextrin on retrogradation degree and viscosity of potato starch.The result shows that four kinds of food additives could improve the retrogradation of potato starch.The effect of guar gum on the retrogradation degree is the most obvious;compared with the starches without any additives,the retrogradation degree is decreased from 33.54% to 16.74%.The effect of carboxymethylcellulose on the viscosity degree is the most obvious,compared with the starches without any additives,the viscosity degree is increased from 4.64 Pa·s to 18.24 Pa·s.%以马铃薯淀粉为原料,研究单硬脂酸甘油酯、羧甲基纤维素钠、瓜尔豆胶及β-环糊精对马铃薯淀粉老化度、粘度的影响。结果表明:4种添加剂均可改善马铃薯淀粉的老化性,瓜尔豆胶降低老化度的作用效果最为明显,与未加任何添加剂的淀粉相比,老化度从33.54%降低至16.74%;羧甲基纤维素钠对马铃薯淀粉老化后粘度的提升最为显著,与未加添加剂的马铃薯淀粉相比,粘度从4.64 Pa·s 提高至18.24 Pa·s。

  15. Production, characterization, and mechanical properties of starch modified by Ophiostoma spp.

    Saville, B. A.


    Full Text Available Microbial modification of starch with Ophiostoma spp. was investigated, with the purpose of developing a novel packaging material for the food or pharmaceutical industries. Various starch sources, such as tapioca, potato, corn, rice and amylopectin were tested as raw materials. The initial screening demonstrated that tapioca and potato starch had better performance for biopolymer production. The yield was about 85%. Preliminary characterization of the modified biopolymer was also conducted. Following microbial conversion, the percentage of molecules with molecular weight (abbreviated Mw more than 10M (abbreviations of million Daltons increased from 25% to 89% after 3 days, confirming that the modification increased the weight of the starch polymer. Fourier Transform Infrared (FT-IR revealed changes in the chemical structure of the starch after the modification. Both pure starches and the modified biopolymers were cast into films and tested for mechanical properties. The tensile tests showed that after treatment with the fungus, the peak stress and modulus of the films increased about 10 and 40 times, respectively. Also, the water barrier property was improved. Therefore, microbial modification positively impacted proper-ties relevant to the proposed application. Although the role of the fungus in the modification and the function-property relationship of the biopolymer are not yet completely clear, the results of this study show promise for development of a novel biopolymer that competes with existing packaging materials.

  16. 用AMMI模型分析马铃薯淀粉品质性状的稳定性%Application of AMMI model on potato starch quality stability analysis

    宿飞飞; 陈伊里; 吕典秋; 王绍鹏; 邱彩玲; 李勇; 刘尚武; 高云飞


    运用AMMI模型分析方法对北方一作区的8个马铃薯品种淀粉品质性状的区试验数据进行稳定性分析.结果表明,延97-8淀粉含量最高、稳定性最好.而且延97-8淀粉产量最高,稳定性较好,并在西宁、兰州和克山地区有最好的适应性;陇薯3号和克新12号的淀粉产量较高,但稳定性较差.%Trial data of starch quality of eight potato varieties from single cropping area in north China were used for stability analyses with AMMI model. The results showed that the variety Yan 97-8 had the highest starch content and the best stability. Besides, Yan 97-8 also had the highest starch output with good stability and the best adaptability in Xining, Lanzhou and Keshan regions, while Longshu 3 and Kexin 12 were high in starch, but were of poor stability.

  17. 天然淀粉的超高压糊化压力研究%Study on gelatinization pressure of starch by ultra high pressure processing

    荆晓艳; 杨留枝; 刘延奇


    在悬浮液浓度为5%(w/v),温度为(20±2)℃时,对8种不同淀粉进行高压处理5min使淀粉发生糊化,采用X射线衍射测试技术得到了各种淀粉完全糊化的压力:小麦淀粉和木薯淀粉约为500MPa,玉米淀粉、荸荠淀粉、糯小麦淀粉和糯米淀粉均为550MPa,糯玉米淀粉约为650MPa,马铃薯淀粉为750MPa.%To study the gelatinization pressures of different kinds of starch at atmospheric temperature, eight different starches chosen as raw materials (5% (w/v) ,at (20 ±2) ℃) by different pressure were treated for 5 min,then the relations between pressure and starch gelatinization were analysed by X ray diffraction. Wheat starch and tapioca starch,500 MPa;corn starch,water chestnut starch,waxy wheat starch and glutinous rice starch,550 MPa;waxy maize starch,650 MPa;potato starch,750 MPa.

  18. Starch granule size strongly determines starch noodle processing and nnodle quality.

    Chen Zenghong,; Schols, H.A.; Voragen, A.G.J.


    Chemical compositions, physical properties, and suitability for starch noodle making of different granule size fractions from potato and sweet potato starches were studied. The ash content, amylose content, phosphorus content, gel firmness, and freeze-thaw stability of small-size granule fractions

  19. Effect of gamma irradiation on thermophysical properties of plasticized starch and starch surfactant films

    Cieśla, Krystyna; Watzeels, Nick; Rahier, Hubert


    In this work the influence of gamma irradiation on the thermomechanical properties of the films formed in potato starch-glycerol and potato starch-glycerol-surfactant systems were examined by Dynamic Mechanical Analysis, DMA, and Differential Scanning Calorimetry, DSC, and the results were correlated to the amount of the volatile fraction in the films.

  20. Concentration and Separation of Active Proteins from Potato Industry Waste Based on Low-Temperature Evaporation and Ethanol Precipitation

    Ahokas, Mikko; Järvinen, Juho; Toivanen, Juho; Tanskanen, Juha P.


    Purpose. Potato fruit juice, a residue of starch industry, contains up to 2.5% [w/w] of proteins that are potentially valuable raw-materials of food, cosmetic, and pharma industries. The recovery of protein from the potato fruit juice is limited by the lack of industrially feasible concentration and separation technologies. The present research thus aimed at development of such process for the separation of active protease inhibitors from potato fruit juice. Methods. Low temperature mechanical vapor recompression evaporation was applied for concentration of potato fruit juice followed by ethanol precipitation for recovery of active proteins. The effects of precipitation temperature and precipitative agents were investigated employing response surface modeling methodology. Results. Concentration of potato fruit juice by evaporation was successful without loss of trypsin inhibition activity. Precipitation using 6.5 M ethanol at low temperature (0–+4°C) was found suitable for the recovery of active protease inhibitors from the concentrate. Piloting at starch industry yielded 50% of total proteins, with a high quantity of active protease inhibitors and a minor inclusion of other proteins. Conclusion. Concentration by low-temperature evaporation, followed by ethanol precipitation of protease inhibitors at optimized temperature, is an attractive option for valorization of potato fruit juice. PMID:28299232

  1. Effects of sorghum (Sorghum bicolor (L.) Moench) tannins on α-amylase activity and in vitro digestibility of starch in raw and processed flours.

    Mkandawire, Nyambe L; Kaufman, Rhett C; Bean, Scott R; Weller, Curtis L; Jackson, David S; Rose, Devin J


    The purpose of this study was to investigate the effects of tannins on starch digestion in tannin-containing sorghum extracts and wholegrain flours from 12 sorghum varieties. Extracts reduced amylase activity in a tannin concentration-dependent manner when the extract was mixed with the enzyme before substrate (amylopectin) addition, with higher molecular weight tannins showing greater reduction. Conversely, when the extract and substrate were combined before enzyme addition an enhancement in amylase activity was experienced. In uncooked, cooked, and cooked and stored wholegrain sorghum flours, rapidly digestible, slowly digestible, and resistant starches were not correlated with tannin content or molecular weight distribution. Resistant starch increased from 6.5% to 22-26% when tannins were added to starch up to 50% (starch weight). Tannin extracts both reduced and enhanced amylase activity depending on conditions, and, while these trends were clear in extracts, the effects on starch digestion in wholegrain flours was more complex.

  2. biodegradation and moisture uptake modified starch-filled linear low ...


    Key words: Starch-LLDPE blends, Calcium chloride, D-glucose, Chloroform and Alumina. INTRODUCTION .... rate of diffusion into the composites this is because moisture uptakes in ... prepared with oxidized potato starch. Food engineering ...

  3. Evaluation of Colocasia esculenta Starch as an Alternative Tablet Excipient to Maize Starch: Assessment by Preformulation and Formulation Studies

    Kusuma. R


    Full Text Available Starch isolated from Colocasia esculenta plant was studied as an alternative pharmaceutical excipient to maize and potato starch. The Colocasia esculenta starch has been evaluated by series of tests as mentioned in Indian Pharmacopoeia before being used for evaluation. It was tested along with maize and potato starch as an alternative excipient by performing battery of preformulation and formulation tests. The results obtained for Colocasia esculenta starch was comparable with maize starch and the Colocasia esculenta starch can be used as a pharmaceutical excipient in tablets preparation.

  4. 挤压加酶玉米初淀粉制备高 DE 值糖浆试验研究%The Experiment Study on Extruded Raw Maize Starch Added Enzyme Used for Production of High DE Value Syrup

    申勋宇; 扬玉平; 申德超


    本试验用单螺杆挤压机对玉米粗淀粉进行挤压加工,研究挤压-糖化系统参数(套筒温度、原料含水率、挤压前加酶量、液化时加酶量和糖化时加酶量)对挤出物制备糖浆的DE值的影响规律。同时,对挤出物制取高DE值糖浆的试验结果进行了验证。%The maize raw starch added enzyme was extruded by single screw .Above extrudate was used for production of maize starch syrup .The influence regularity of extrusion-saccharification system parameters which include the barrel tem-perature , moisture content percentage of raw maize starch ,enzyme dosage added before extrusion , enzyme dosage added while liquifying , enzyme dosage added when saccharifying on the syrup DE value was studied in this paper .Meanwhile the experiment results for production of high DE value syrup were verified .

  5. Quality Evalution of Potato Clones as Processed Material Cultivated in Lembang

    Rahayu, S. T.; Handayani, T.; Levianny, P. S.


    Potatoes are widely grown in the temperate as well as tropical zones and are the fourth largest staple crop in the world after maize, wheat and rice. The study aimed to evaluate the quality of several potato clones as raw material on potato based products (chips and boiled). The study was conducted at Indonesian Vegetable Research Institute, Lembang about 1200 m asl height, in 2016. The design used was a randomized complete block design with three replications. The samples tested were 5 clones selection (clones number 1,2,3,4,10). In this study, variety Granola (Clone number 6) and Atlantic (Clone number 7) were used as a susceptible control, meanwhile the Katahdin (Clone number 8) and SP 951 (Clone number 9) were used as the resistant control. Chemical properties tested were starch, reduction sugar, water content, specific gravity, and Total Soluble Solute (TSS). The organoleptic assessment method used was hedonic test with scale of 1-5 (very like until very dislike) which had been done by 15 untrained panelists. Data was statisticaly analized by Duncan’s test (5%). Clone 1 and 2 were preferred by panelist as raw material for potato chips, which got score of ‘very like’ until ‘like’ for color, size, taste, and texture parameters. Although there was no significant difference on color and size parameters for all samples of that boiled potato there, however, clone no 8 can be considered as the most favourite based on taste and texture parameters.

  6. Potato fiber as a dietary fiber source in dog foods.

    Panasevich, M R; Rossoni Serao, M C; de Godoy, M R C; Swanson, K S; Guérin-Deremaux, L; Lynch, G L; Wils, D; Fahey, G C; Dilger, R N


    Potato fiber (PF), a coproduct of potato starch manufacture, was evaluated as a potential novel fiber source in dog food. Potato fiber contained 55% total dietary fiber, 29% starch, 4% crude protein, and 2% acid-hydrolyzed fat. The PF substrate was evaluated for chemical composition, in vitro digestion and fermentation characteristics, and in vivo responses. For the in vitro hydrolytic-enzymatic digestion and fermentation experiment, raw and cooked PF substrates were first subjected to hydrolytic-enzymatic digestion to determine OM disappearance and then fermented using dog fecal inoculum. Fermentation characteristics were then measured at 0, 3, 6, 9, and 12 h. For the in vivo experiment, 10 female mixed-breed dogs (6.13±0.17 yr; 22±2.1 kg) were provided 5 diets with graded concentrations (0%, 1.5%, 3%, 4.5%, or 6%) of PF in a replicated 5×5 Latin square design. Dogs were acclimated to the test diet for 10 d, followed by 4 d of total fecal collection. Fresh fecal samples were collected to measure fecal pH and fermentation end products. In vitro digestion revealed that raw and cooked PF were 32.3% and 27.9% digested enzymatically, whereas in vitro fermentation showed that PF was fermentable through 9 h. Raw PF had greater (Pdietary fiber digestibility exhibited a linear increase (Pdietary PF. Fecal protein catabolite concentrations were low or undetectable, with the exception of spermidine, which exhibited a linear increase with increasing concentrations of PF. These findings indicated that inclusion of PF elicited favorable fermentation characteristics without negatively affecting nutrient digestibility or stool characteristics, indicating that PF could be a functional dietary fiber source in dog foods.

  7. Effect of acid hydrolysis combined with moist heat treatment on physicochemical properties of potato starch%酸热处理对马铃薯淀粉理化性质的影响

    邱超; 姬娜; 朱晓蕾; 熊柳; 孙庆杰


    The effect of pH value,moisture content and temperature on modification of potato starch (PS) was studied.The result showed that after being treated by partial acid hydrolysis (AH)combined with heat moisture treatment (HMT),the amylose content in PS increased,while soluble amylose content de-creased;Solubility and swelling power of most modified starches decreased;Peak viscosity (PKV ), trough viscosity (TV),final viscosity (FNV),attenuation and setback decreased;But gel hardness of some modified starches was higher than native starch.The biggest hardness of starch gel was 143.42 g, which was about 4.2 times higher than native PS,while gel springiness and cohesiveness of all modified starches decreased.To,Tc,Tp and Tc-To of PS modified starches significantly increased,butΔH de-creased.Crystallized potato starch was B-type,the peak of modified PS at 5.9°(2θ)decreased,double peak at 22~25 °(2θ)decreased too,and even became into a single wide peaks.%以马铃薯淀粉为原料,研究不同pH值、水分含量和处理温度对马铃薯淀粉复合改性效果。结果表明,马铃薯淀粉经部分酸解结合湿热处理复合改性后,直链淀粉含量增加,但可溶性直连淀粉含量降低。复合改性后马铃薯淀粉溶胀度和溶解度降低。经部分酸解结合湿热处理改性后马铃薯淀粉的峰值黏度(PKV)、谷值黏度(TV)、终值黏度(FNV)、衰减值(BD)和回生值(SB)都降低。但是复合改性后马铃薯淀粉的凝胶硬度增加,最大的硬度达到了143.42 g,是原淀粉的4.2倍,而黏度、内聚力都降低。复合改性后马铃薯淀粉的To、Tp、Tc 和Tc -To都显著升高,但ΔH显著降低。X-衍射测定结果表明马铃薯淀粉结晶为B型,复合改性后马铃薯淀粉在5.9°(2θ)产生的B型特征峰减小,在22~25°(2θ)出现的双峰减小,甚至有变为单峰的趋势。

  8. Effects of alpha-amylase reaction mechanisms on analysis of resistant-starch contents.

    Moore, Samuel A; Ai, Yongfeng; Chang, Fengdan; Jane, Jay-lin


    This study aimed to understand differences in the resistant starch (RS) contents of native and modified starches obtained using two standard methods of RS content analysis: AOAC Method 991.43 and 2002.02. The largest differences were observed in native potato starch, cross-linked wheat distarch phosphate, and high-amylose corn starch stearic-acid complex (RS5) between using AOAC Method 991.43 with Bacillus licheniformis α-amylase (BL) and AOAC Method 2002.02 with porcine pancreatic α-amylase (PPA). To determine possible reasons for these differences, we hydrolyzed raw-starch granules with BL and PPA with equal activity at pH 6.9 and 37°C for up to 84 h and observed the starch granules displayed distinct morphological differences after the hydrolysis. Starches hydrolyzed by BL showed erosion on the surface of the granules; those hydrolyzed by PPA showed pitting on granule surfaces. These results suggested that enzyme reaction mechanisms, including the sizes of the binding sites and the reaction patterns of the two enzymes, contributed to the differences in the RS contents obtained using different methods of RS analysis.

  9. Acid resistance of starch granules

    Nara, S.; Sakakura, M.; Komiya, T.


    When potato starch was hydrolyzed to form Naegeli amylodextrin by 16% sulfuric acid at 30/sup 0/C, only the amorphous portion of the starch granules was deteriorated. The crystallinity of Naegeli amylodextrin showing the hydrolysis ratio of 0.22 was 1.28 times as large as that of original starch. The hydrolysis process at above 45/sup 0/C was given by two exponential equations. The value of acid resistance portion (C/sub 0/) at 30 and 38/sup 0/C was 100%, while the values at 45, 50 and 55/sup 0/C were 67, 38 and 18%, respectively. The high value of C/sub 0/ generally showed the high acid resistance in the various starches. Sweet potato and waxy rice starches were more easily hydrolysed than other starches, although they gave the relatively high value of C/sub 0/. Thus, it was slightly more difficult for low acid resistance portion of potato starch to be hydrolyzed than for that of other starches. Moreover, that of waxy rice was easily hydrolyzed.

  10. 紫薯挂面加工工艺研究%Processing Technology of Vermicelli with Purple Sweet Potato

    苑建伟; 谢新华; 李巍


    以小麦粉和紫薯为主要原料,采用以紫薯泥代替紫薯淀粉的方法,对紫薯挂面的制作工艺进行研究。通过正交试验确定了生产紫薯挂面的最佳配方为紫薯与小麦粉比例3∶7、水添加量31%和谷朊粉添加量1.5%。用此配方生产的紫薯挂面色泽鲜艳,具有紫薯特有的香味,断条率低,口感良好,营养丰富。%Taking wheat flour and purple sweet potato as raw material, new technology of adding purple mashed potatoes instead of purple sweet potato starch was applied to study production process of purple sweet potato vermicelli. Optimum parameters of vermicelli with purple sweet potato were confirmed by orthogonal experiment.Results showed that ratio of purple sweet potato to wheat flour was 3∶7, water was 31%, wheat gluten was 1.5%.Product had bright color, special purple sweet potato flavor, low rate of broken bars, good taste and rich in nutrition.

  11. Preparation of Carboxymethyl Potato Starch with Ethanol Method and Product Characterization%乙醇溶剂法制备羧甲基马铃薯淀粉及特征分析

    王鲁峰; 魏鹏娟; 缪文华; 徐晓云; 傅虹飞; 潘思轶


    Carboxymethyl potato starch was synthesized using ethanol as solvent by single and multi - step processes, and the products were analyzed with infra -red spectra, X-ray diffractogram, thermogravimetric analysis, scanning electronic microscopy, 13C -NMR and UV scanner. Results; DS of 0.75 and RE of 75% is the record of the single - step process, while DS of 1.06 and RE of 35.3% is that of the multi - step process. The microstruc-ture of the starch produced dramatically varies after the carboxymethylation; the crystallization degree decreases greatly and thermal stability increases. The substituent occurs mainly at C - 2 and C - 6 while the substituent of C - 3 is neglectable. The transmission of visible light of the carboxymethyl starch solution is much better than the original potato starch.%以乙醇为溶剂通过单步反应和多步反应制备了羧甲基马铃薯淀粉,并采用红外光谱、X-衍射、热重分析、扫描电镜、~(13)C核磁共振、紫外扫描对产品进行了分析.单步反应时取代度可以达到0.75,反应效率75%,多步反应时取代度可以达到1.06,反应效率35.3%.分析显示:淀粉微观结构发生了显著变化,结晶度大幅下降,热稳定性上升,取代位点主要分布在C-2、C-6位点上,C-3位点取代度很小,产品溶液在可见光区的透光性相对于原淀粉有极大提高.

  12. Advances and Trends in Utilization of Potato Pulp from Potato Starch Processing%马铃薯渣综合利用研究现状及发展趋势

    李芳蓉; 韩黎明; 王英; 刘玲玲; 童丹


    Nutrients and the main properties of potato pulp were introduced. And status of potato pulp utilization were summarized, including production of high-protein feed, preparation of dietary fiber and pectin, preparation of alcohol fuel and potato pulp novel adsorbent and binder, and preparation of feed Koji, oil and fat packaging edible film of instant noodle and organic chemical products. The problems of potato pulp utilization were analyzed, i.e. low utilization rate, food security issue and difficult technique extension. Application prospects and development trends of the potato pulp were forecasted. Potato pulp could be used in extraction of dietary fiber and pectin, increasing added value and economic efficiency. Protein feed or feed production from solid-state fermentation of potato pulp might have the most development potential for potato pulp processing. Use of potato pulp for production of fermentation medium might be a value-added research direction. Potato pulp preparation for alcohol fuel and biomass fuel mix production could be another way for use of potato pulp. Use of potato pulp for production of both dietary fiber and alcohol fuel could be a new idea for potato pulp comprehensive utilization worth exploring.%介绍了马铃薯渣营养成分及主要性质,综述了马铃薯渣综合利用研究现状,包括生产高蛋白饲料、制备膳食纤维和果胶,制备燃料酒精和薯渣新型吸附剂和粘结剂、制备饲料种曲、方便面油料包可食性膜和有机化工产品等。剖析了马铃薯渣综合利用中存在的问题,即综合利用率低、食用安全性问题、技术推广困难。展望了马铃薯渣的开发应用前景与发展趋势。马铃薯渣提取膳食纤维和果胶,薯渣加工附加值提高,经济效益较高;固态发酵马铃薯渣生产蛋白饲料或生产配合饲料是薯渣处理最具发展潜力的方向。利用薯渣制作发酵培养基是进行薯渣增值的研究方向;利用

  13. Effect of Plasticizers on Physical and Mechanical Properties of Potato Starch- based Composite Films%增塑剂对马铃薯淀粉基复合膜物理机械性能的影响

    贾超; 王利强; 卢立新; 赵艺程


    Potato starch based composite films were prepared by casting using potato starch, pullulan, gelatin as film forming material, calcium chloride as cross-linking agent, and glycerol, sorbitol, and polyethylene glycol as plasticizer. The effects of three kinds of plasticizers on physical and mechanical properties of composite films were studied. The results showed that tensile strength and Young's modulus of the composite films decrease significantly with plasticizer contents; elongation increases significantly with glycerol and sorbitol contents; effect of polyethylene glycol on elongation is not obvious; water vapor permeability and water solubility of composite films increase with plasticizer contents; polyethylene glycol can reduce the light transmission rate of the composite films significantly.%以马铃薯淀粉、普鲁兰多糖、明胶为成膜物质,氯化钙为交联剂,甘油、山梨醇、聚乙二醇为增塑剂,采用流延法制备了马铃薯淀粉基复合膜,研究了3种增塑剂对复合膜物理机械性能的影响。结果表明:复合膜的抗拉强度和弹性模量均随增塑剂含量的增加而显著减小,断裂伸长率随甘油和山梨醇含量的增加而显著增加,聚乙二醇对其影响不显著;复合膜的水蒸气透过率和水溶性均随增塑剂含量的增加而增加;聚乙二醇能够显著降低复合膜的透光率。

  14. Encapsulation altered starch digestion: toward developing starch-based delivery systems.

    Janaswamy, Srinivas


    Starch is an abundant biomaterial that forms a vital energy source for humans. Altering its digestion, e.g. increasing the proportions of slowly digestible starch (SDS) and resistant starch (RS), would revolutionize starch utility in addressing a number of health issues related to glucose absorption, glycemic index and colon health. The research reported in this article is based on my hypothesis that water channels present in the B-type starch crystalline matrix, particularly in tuber starches, can embed guest molecules such as nutraceuticals, drugs, flavor compounds and vitamins leading to altered starch digestion. Toward this goal, potato starch has been chosen as the model tuber starch, and ibuprofen, benzocaine, sulfapyridine, curcumin, thymol and ascorbic acid as model guest molecules. X-ray powder diffraction and FT-IR analyses clearly suggest the incorporation of guest molecules in the water channels of potato starch. Furthermore, the in vitro digestion profiles of complexes are intriguing with major variations occurring after 60 min of starch digestion and finally at 120 min. These changes are concomitantly reflected in the SDS and RS amounts, with about 24% decrease in SDS for benzocaine complex and 6% increase in RS for ibuprofen complex, attesting the ability of guest molecule encapsulation in modulating the digestion properties of potato starch. Overall, this research provides an elegant opportunity for the design and development of novel starch-based stable carriers that not only bestow tailored glucose release rates but could also transport health promoting and disease preventing compounds.

  15. Effect of thermal and chemical modifications on the mechanical and release properties of paracetamol tablet formulations containing corn, cassava and sweet potato starches as filler-binders

    Mariam Vbamiunomhene Lawal


    Conclusions: Modification of the experimental starches improved the mechanical and release properties of directly compressed paracetamol tablet formulations. Thus, they can be developed for use as pharmaceutical excipients in specific formulations.

  16. Substituent distribution in highly branched dextrins from methylated starches

    Vliegenthart, J.F.G.; Burgt, Y.E.M. van der; Bergsma, J.; Bleeker, I.P.; Mijland, P.J.H.C.; Kamerling, J.P.


    Granular potato starch and amylopectin potato starch were methylated to molar substitutions (MS) up to 0.29. Extensive alpha-amylase digestion gave mixtures of partially methylated oligomers. Precipitation of larger fragments by methanol yielded mainly alpha-limit dextrins (84–99%). Methanol precipi

  17. Substituent distribution in highly branched dextrins from methylated starches

    Vliegenthart, J.F.G.; Burgt, Y.E.M. van der; Bergsma, J.; Bleeker, I.P.; Mijland, P.J.H.C.; Kamerling, J.P.


    Granular potato starch and amylopectin potato starch were methylated to molar substitutions (MS) up to 0.29. Extensive alpha-amylase digestion gave mixtures of partially methylated oligomers. Precipitation of larger fragments by methanol yielded mainly alpha-limit dextrins (84–99%). Methanol precipi

  18. Substituent distribution in highly branched dextrins from methylated starches

    Vliegenthart, J.F.G.; Burgt, Y.E.M. van der; Bergsma, J.; Bleeker, I.P.; Mijland, P.J.H.C.; Kamerling, J.P.


    Granular potato starch and amylopectin potato starch were methylated to molar substitutions (MS) up to 0.29. Extensive alpha-amylase digestion gave mixtures of partially methylated oligomers. Precipitation of larger fragments by methanol yielded mainly alpha-limit dextrins (84–99%). Methanol

  19. Improvement of hydrocyclone installations for starch production lines

    N. R. Andreev


    Full Text Available Multicyclonic installations contain up to 15 steps of division (multicyclones. Improvement of work quality at the reduction of quantity of steps of division can be reached by increasing an starch yield from the step with the reduction of an exit of a liquid phase. To achieve that, a connection of three multicyclones according to the cross scheme is used as for a step of division instead of a separate multicyclone. It is shown that at the three multicyclones a step of division of change in redistribution of suspension components is created the design solution of the division step where liquid products are going out with only to liquid ones, and condensed products – only with condensed ones. At this step the starch yield increases in the condensed product while reducing the end product volume; therefore is received in one step the higher quality starch because of its increased quantity in the condensed descent product step. However, at such connection of multicyclones starch gets to a liquid descent of each step, therefore it is condensed additionally to release starch by con-necting of four multicyclones in to one step of division. New multistage multicyclonic installation consists of 12 multicyclones instead of 15 ones. That reduces capital and operational costs. Thus, varying manipulating the scheme of microcyclones connection in the unit, it is possible to receive the required technological result with the improved economic indicators. AllRussian Research Institute of starch products has developed lines of potato processing for dry starch on the basis 10 and 50 t / per day of initial raw materials using hydrocyclone installations. That allows to organize a new production without big capital expenditures. The hydrocyclone design with the changed external way of supply of suspension is developed at which the flow enters the already rotating product to exclude the influence of an inflow on the quality of suspension fractionation.

  20. Native protein recovery from potato fruit juice by ultrafiltration

    Zwijnenberg, Harmen Jan; Kemperman, Antonius J.B.; Boerrigter, M.E.; Lotz, Martin; Dijksterhuis, Jan F.; Koops, G.H.; Poulsen, Poul Emil


    Potato fruit juice, i.e. the stream resulting after the extraction of the starch from the potato, contains up to 2.5% [w/w] of proteins that are potentially valuable for the food market. However, today the recovery of protein from the potato fruit juice with reverse osmosis membranes results in a

  1. Amylose content decreases during tuber development in potato

    Potato starch is composed of amylopectin and amylose in an approximately three to one ratio. Amylose is considered to be nutritionally desirable, so there is interest in finding strategies to increase the amylose content of potatoes. There is also interest in marketing “baby” potatoes, which are har...

  2. Physico-chemical and functional properties of potato proteins.

    Koningsveld, van G.


    Key words: potato proteins, patatin, protease inhibitors, solubility, structure, pH, temperature, ethanol, ionic strength, phenolic compounds, foams, emulsionsIn potato starch manufacture an aqueous byproduct remains that is called potato fruit juice (PFJ). On a dry matter basis PFJ

  3. Occurrence and physico-chemical properties of protease inhibitors from potato tuber (Solanum tuberosum)

    Pouvreau, L.A.M.


    Potato proteins are present in a by-product of the potato starch industry, the so-called potato juice. They are recovered by an acidic heat-treatment of the potato juice. This results in a completely irreversible precipitation of the proteins, with a complete loss of functionality for food

  4. Study on the Physical Properties of Several Kinds of Starches%几种不同淀粉的物性分析研究

    张森; 张春华; 黄蔚霞; 朱克瑞; 张媛媛; 苏宇辰; 尤梦圆


    以玉米淀粉、蜡质玉米淀粉、马铃薯淀粉、马铃薯酯化变性淀粉、木薯淀粉和木薯醋酸酯淀粉为原料,比较研究了激光粒度仪和X-射线衍射仪测定的淀粉的颗粒大小和结构,快速粘度仪测定糊化特性,差示扫描量热仪和热重分析仪测定淀粉的热特性。结果表明,淀粉的平均粒径大小顺序为马铃薯类淀粉>玉米类淀粉>木薯类淀粉,且湿法和干法测定有差异;玉米淀粉、木薯淀粉和木薯醋酸酯淀粉为A型结构,蜡质玉米淀粉经过变性处理无双峰结构,马铃薯及其酯化变性淀粉为B型结构;马铃薯淀粉峰值粘度最大,热焓值最高,持水力最强,玉米淀粉的糊化温度最高,峰值粘度和衰减值最小,马铃薯酯化淀粉的起始糊化温度最低,综合持水力最弱。%Corn starch, waxy corn starch, potato starch, potato cross-linking modified starch, cassava starch and tapioca acetate starch were chosen as raw materials. Granule size, structure, pasting properties and thermal characteristics of starch were measured by laser particle size analyzer, X-ray diffraction rapid viscosity analyz-er, differential scanning calorimetry and thermal gravimetric analyzer. The results showed that the average parti-cle size of potato starch was the biggest and cassava starch was the smallest among the starch, the dry method was different with wet method. Corn starch, cassava starch and tapioca acetate starch have type A structure, potato and its modified starch have the characteristics of type B structure. The peak viscosity ,enthalpy and wa-ter holding capacity of potato starch was a high value. The pasting temperature of corn starch was the highest, and the peak viscosity and the breakdown value were the least. The initial pasting temperature of potato starch was the lowest, and the water holding capacity was the weakest.

  5. Recrystallization of amylopectin in concentrated starch gels

    Keetels, CJAM; Oostergetel, GT; vanVliet, T


    The relation between the recrystallization of amylopectin and the increase in stiffness of starch gels during storage was studied by various techniques. From transmission electron microscopy it was concluded that the size of the crystalline domains in retrograded 30% w/w potato starch gels was about

  6. The Acetylation of Starch by Reactive Extrusion

    Graaf, Robbert A. de; Broekroelofs, Annet; Janssen, Léon P.B.M.


    Potato starch has been acetylated in a counter rotating twin screw extruder using vinylacetate and sodium hydroxide. The desired starch acetylation reaction is accompanied by an undesired parallel base catalysed hydrolysis reaction of vinylacetate and a consecutive hydrolysis reaction of the acetyla

  7. 淀粉分子结构对形成抗性淀粉的影响%Influence of Molecular Structure of Starch on Formation of Resistant Starch

    衣杰荣; 姚惠源


    考察了几种大米淀粉和土豆淀粉形成抗性淀粉的能力,用分子排阻色谱的方法研究其分子结构。认为土豆淀粉比大米淀粉更适宜用来生产抗性淀粉。%The formation of resistant starch from several kinds of rice starch and potato starch was investigated. The resistant starch yield produced from potato starch was more than that of the rice strach. The molecular structure of starch was studied using the exclusion chromato graphy. It showed that the potato starch was more appropriate to produce resistant starch comparing with the rice starch.

  8. [Evaluation of culture media for detecting the starch hydrolysis reaction in pathovars of Xanthomonas campestris].

    Alippi, A M


    Sixty strains of different pathovars of Xanthomonas campestris have been tested for the evaluation of various starch agars and compounds of starch degradation on six media: soluble starch, potato insoluble starch, corn insoluble starch, potato amylopectin, corn amylopectin and potato amylose. The purpose of the present investigation was the selection of the most suitable medium for the visualization of the starch hydrolysis test, presenting this reaction as a distinct character between pathovars of the Xanthomonas campestris group. From 60 strains tested, 74% gave positive reactions. Pathovars holcicola, pelargonii, pruni and vitians were negative. Regarding X. campestris pv. vesicatoria cultures, results were variable. Potato and corn insoluble starch agars were the most suitable media for the visualization of the starch hydrolysis reaction and at the same time the most appropriate for direct isolation. Differentiation at species level could be practicable, but within the Xanthomonas campestris group, variation amongst pathovars suggest the unsuitability of the test in spite of the high percentage of positive reactions.

  9. The influence of various small plasticisers and malto-oligosaccharides on the retrogradation of (partly) gelatinised starch

    Smits, A.L.M.; Kruiskamp, P.H.; Soest, van J.J.G.; Vliegenthart, J.F.G.


    Ageing of gelatinised and partly gelatinised potato starch and wheat starch were investigated in the presence of plasticisers with increasing size and number of OH groups (ethylene glycol, glycerol, threitol, xylitol, glucose, and for potato starch also maltose). The influences of these plasticisers

  10. Preparation and characterization of new and improved soluble-starches, -amylose, and -amylopectin by reaction with benzaldehyde/zinc chloride.

    Johnston, David A; Mukerjea, Rupendra; Robyt, John F


    Seven different starches from potato, rice, maize, waxymaize, amylomaize-VII, shoti, and tapioca, and potato amylose and potato amylopectin have been reacted with benzaldehyde, catalyzed by ZnCl(2), to give new water-soluble starches and water soluble-amylose and soluble-amylopectin. In contrast to the native starches, aqueous solutions of the modified starches could not be precipitated with 2-, 3-, or 4-volumes of ethanol. β-Amylase gave no reaction with the modified starches, in contrast to the native starches, indicating that the modification occurred exclusively at the nonreducing-ends, giving 4,6-benzylidene-D-glucopyranose at the nonreducing-ends. Reactions of α-amylase with native and modified potato and rice starches gave a decrease in the triiodide blue color and an increase in the reducing-value that were similar for the native- and modified-starches, indicating the modified starches had not been significantly altered by the modification. The benzaldehyde-modified starches and benzaldehyde-modified potato amylose and potato amylopectin components, therefore, have a starch structure very much like their native counterparts, in contrast to the Lintner, Small, and the alcohol/acid-hydrolyzed soluble-starches that have undergone acid hydrolysis. The benzaldehyde-modified starches and starch components have significantly higher water solubility than their native counterparts even though the structures of the modified starches had only been slightly altered from the structures of their native counterparts. They all gave crystal-clear solutions that did not retrograde.

  11. Optimization of Enzyme Hydrolysis Conditions of Sweet Potato Starch by Response Surface Methodology%响应面法优化甘薯淀粉酶解条件的研究

    李忠海; 刘建军; 钟海雁; 鲁海波; 史云丽


    Based on single - factor experiments including factors such as thermostable α - amylase dosage, time, temperature and pH in sweet potato starch hydrolysis, the response surface methodology was adopted using reducing sugar amount as evaluating indicator to optimize the process, and to establish a mathematical model. Results: The optimum hydrolysis parameters are enzyme dosage 55 U/mL, time 80 min and temperature 90 ℃. The value of reducing sugar and hydrolysis rate of starch is 3.706 g/mL and 75.33 % respectively at the optimum conditions. The drink gained after filtration of the hydrolyzed sweet potato juice has no deposition in preservation period without adding stabilizer, indicating the perfect stability of this beverage.%在加酶量、作用时间、反应温度及pH四个单因素试验的基础上,运用响应面分析法,以甘薯汁中还原糖量为评价指标,对耐高温α-淀粉酶酶解甘薯汁中淀粉的最佳工艺进行了研究,并利用统计学方法建立了耐高温α-淀粉酶酶解甘薯汁中淀粉的二次多项数学模型.结果表明,最佳酶解条件为:加酶量55 U/mL;作用时间80 min;反应温度90℃.在最佳酶解条件下,甘薯汁中还原糖量达3.706 g/100mL,淀粉的酶解率为75.33%.水解后的甘薯汁过滤制得的饮料,无需添加稳定剂,即可达到饮料稳定性的理想效果,在饮料保存期内无沉淀产生.

  12. 阿魏酸对马铃薯淀粉基复合膜性能的影响%Effect of ferulic acid on properties of potato starch-based composite films

    贾超; 王利强; 卢立新; 谢甲有


    以马铃薯淀粉、普鲁兰多糖、明胶为成膜物质,甘油为增塑剂,阿魏酸为交联剂,采用流延法制备马铃薯淀粉基复合膜,研究了阿魏酸含量对复合膜物理机械性能的影响.结果表明:阿魏酸能够改善复合膜的机械性能和阻湿性能,减小复合膜的水溶性,但会显著降低复合膜的透光率,且使复合膜的颜色发黄.其中,添加1%阿魏酸的复合膜性能较好,其抗拉强度为14.33MPa,断裂伸长率为9.36%,水蒸气透过率为4.52g· mm·m-2·d-1·kPa-1,水溶性为28.46%,透光率为77.37%.%Potato starch-based composite films were obtained by casting using potato starch, pullulan, gelatin as film-forming material,glycerol as plasticizer,ferulic acid as cross-linking agent.The effect of the contents of ferulic acid on physical and mechanical properties of composite films were investigated.The results showed that ferulic acid improved the mechanical properties and moisture barrier properties of the composite films, reduced the water-solubility of the composite films. However, it reduced the light transmission rate of the composite films significantly,and made the color of the composite films yellow.The properties of composite films containing 1% ferulic acid were better, the tensile strength was 14.33MPa, elongation at break was 9.36%, water vapor permeability was 4.52g·mm·m-2·d-1·kPa-1, water- solubility was 28.46%, light transmission rate was 77.37%.

  13. Study on the Experiment Parameter of Determination of Raw Starch Content for Brewing Rice%酿酒大米中粗淀粉含量检测实验参数研究

    孙清华; 谢小兰; 刘建文; 严伟


    When the starchs in rice is detecting its content,The other materials composition in rice,For example;Fat,protein and soluble sugar,Which can also generate the reducing substances like glucose when it in the hydrolysis process.If the rest of matters in rice don't removefromthesample,In the experimental process,The determination numericals of starch content will have somewhat increase,The processoftestingisthedeterminationofrawstarchcontent.In fact,which increase is not come from the starchs in sample.In the process of testingstarchcontentusingacidhydrolysis,The most three important key influence factors for acid hydrolysis of starch and redox titration, which is the acid concentration,water bath reflux time and the power of hydrogen after sample neutralization,gets through the orthogonal optimizationexperiment.It's expect to find the accurate testing datas which is nearest the real starch content in the process of raw starch contentdetemination.At the shorten testing time and improve the efficiency of inspection same time,It's hope to get the most accurate and real experimental results of starch.%大米中的淀粉在进行含量测定时,存在于大米中的其他化合物成分,如脂肪、蛋白质和可溶性糖等在水解过程中也会生成与葡萄糖一样具有还原性的物质,这些其余的物质成分如若不除去,所进行的检测即为粗淀粉含量的测定,在实验过程中淀粉含量的测定数值会有所增加,但实际上,这些所增加的数值并不是由样品中的淀粉所增加的。在酸水解法测定淀粉含量的过程中,通过对影响淀粉水解的因素,即酸的浓度和水浴回流时间以及影响氧化还原滴定的因素,即中和后样液的酸碱度这三个关键因素进行正交优化实验,以期找到粗淀粉检测步骤中所获实验数值最接近于样品中淀粉真实数值的实验参数。在缩短实验时间和提高检验效率的同时,以期获得最准确、最真实的实验数据。

  14. Enzymolysis Technology of Sweet Potato Starch by Response Surface Method and Its Kinetic Modeling%响应面法优化甘薯淀粉酶解工艺及动力学模型研究

    高义霞; 牛伟强; 高小刚; 周向军


    To study enzymolysis technology of sweet potato starch and its kinetic modeling,the releasing rate of glucose was taken as an index,and the effects of hydrolysis time,enzyme adding amount,starch concentration,pH and hydrolysis temperature of enzymatic hydrolysis of sweet potato starch have been explored.Single experiment and response surface method have been applied to optimize enzymolysis.At the same time,Michaelis constant (Km), maximum velocity (Vm)and corresponding kinetic equation were also calculated by Lineweaver -Burk Plotting and Wilkinson Statistical Method.The results showed that the optimal enzymolysis parameters were 40 min,60 ℃,pH 5. 0,enzyme adding amount of 0.6 U /mL,and starch concentration of 5 mg/mL.On this conditions,verification value was ((50.676 ±0.294)%,n =5),RSD =0.519%.At pH 6.0 and 50 ℃,Ea =31.986 kJ/moL,Km and Vm were 0.988 mg/mL and 0.107 mg/(mL·min)respectively.%研究甘薯淀粉的α-淀粉酶酶解工艺及动力学。以葡萄糖释放率为考察指标,研究酶解时间、酶量、淀粉浓度、pH 值及酶解温度对α-淀粉酶酶解甘薯淀粉的影响,利用单因素和响应面法优化酶解工艺。通过 Lineweaver -Burk 和 Wilkinson 统计法求解米氏常数(Km )和最大反应速度(Vm ),建立相应动力学模型。结果表明:α-淀粉酶酶解甘薯淀粉最优参数为:时间40 min,温度60℃,pH 5.0,酶量0.6 U /mL 和淀粉质量浓度5 mg/mL,在此条件下,验证值为(50.676±0.294)%,n =5,RSD =0.519%。在 pH 6.0,50℃条件下,活化能(Ea)=31.986 kJ/moL,Km =0.988 mg/mL,Vm =0.107 mg/(mL·min)。

  15. 增塑剂甘油对甘薯淀粉膜性能的影响研究%Effect of Glycerol Plasticizer on the Properties of Sweet Potato Starch -Based Films

    刘鹏飞; 孙圣麟; 王文涛; 侯汉学; 董海洲


    采用甘油作为增塑剂制备甘薯淀粉膜,研究了甘油/淀粉比对甘薯淀粉膜性能的影响。结果表明:加入甘油后,淀粉糊各特征点黏度值发生不同程度的变化;随着甘油量的增加,膜的断裂伸长率和水蒸气透过率呈递增的趋势,淀粉膜的热封性能逐步得到提高,抗拉强度呈递减的趋势;随着甘油的加入,膜的透光率增大;甘油分子与淀粉分子之间有较弱的作用,在2θ=14.8°处产生了一个新的峰;淀粉颗粒的分散和分布随着甘油的加入有明显改善,淀粉膜表面变得平整;紫外老化试验表明随着甘油量的增加,延缓了淀粉膜的老化作用。当甘油/淀粉比在0.3/1~0.4/1之间时,甘油和淀粉的相容性较好,甘油对淀粉有较好的塑化效果。%Sweet potato starch (SPS)-based films have been prepared with glycerol as plasticizer.The influ-ence of glycerol /starch of different ratios on the films properties has been studied in the paper.The results showed that the glycerol could significantly change SPS pasting characteristics.With the increase of glycerol content,the e-longation at break,as well as the water vapor permeability gradually increased,while the tensile strength gradually decreased.The films exhibited a better heat endurance with the increasing content of glycerol.The addition of glycer-ol could raise the light transmission of films.The glycerol and starch molecules had weaker interaction;a new peak was produced after the addition of glycerol,between the 2 theta,at 14.8°.The dispersion and distribution of the starch granules were improved significantly,and the surface of the films became smooth since adding glycerol.The retrogradation of the films was delayed by the increasing content of the glycerol.These results indicated that the glyc-erol has a good compatibility and rather better plasticizing effect with the starch matrix when the ratios of glycerol /starch

  16. 多层瓦楞纸淀粉胶的性能%Properties of Starch Adhesive for Multi-layer Corrugated Paper



    Starch adhesive for the multi-layer corrugated paper line was prepared with corn starch , wheat starch and potato starch as raw starch materials by way of Stein-Hall with different proportion to study the properties of starch adhesive .With the increase of adhesive concentration and the content of NaOH , the pasting temperature was decreased .With the increase of the content of NaOH , the Stein-Hall viscosity was decreased at first and then increased rapidly when the content of NaOH was beyond 0.7%;at the same temperature , the Brabender viscosity in the descending order was:potato starch adhesive , wheat starch adhesive , and corn starch adhesive .For the same storage time , the Brabender viscosity in the descending or-der was:potato starch adhesive , corn starch adhesive , and wheat starch adhesive .%分别以玉米淀粉、小麦淀粉、马铃薯淀粉为原料,采用二步法按不同配比制备多层瓦楞纸生产线用淀粉胶黏剂,并对其性能进行研究。结果表明,糊化温度随淀粉胶质量分数和NaOH质量分数的增大而降低;Stein-Hall黏度随NaOH质量分数增大先减小,当NaOH质量分数超过0.7%时,Stein-Hall黏度迅速增大。在同一温度时,Brabender黏度从大到小依次为马铃薯淀粉胶、小麦淀粉胶、玉米淀粉胶;经过同一放置时间时,Brabender 黏度从大到小依次为马铃薯淀粉胶、玉米淀粉胶、小麦淀粉胶。

  17. The structure and properties of different types of starch exposed to UV radiation: a comparative study.

    Bajer, Dagmara; Kaczmarek, Halina; Bajer, Krzysztof


    The effect of UV-irradiation on four different types of native starch (corn, waxy corn, wheat and potato) have been investigated. Although the changes in the chemical structure of starch specimens were small, indicating good photostability, the samples lost adsorbed water and their crystallinity degree decreased after irradiation. Moreover, a drop in average molecular weight occurred in samples (with the exception of potato starch) as a result of main chain scission. The variations in the properties of investigated specimens of various origin were related to the differences in their structure and macromolecular arrangement. The lowest photostability among the four starches was exhibited by potato starch.

  18. High surface area starch products as filler-binder in direct compression tablets

    te Wierik, G.HP; Ramaker, J.S; Eissens, A.C; Bergsma, J; Arends-Scholte, A.W.; Lerk, C.F


    Amylodextrin and modified starch products were prepared from amylose-free starches and from (amylose containing) potato starch by enzymatic degradation, followed by precipitation and filtration. The intermediate retrograded starch products were dehydrated by drying at room temperature or washing wit




    A two-phase kinetic model is presented for the base-catalyzed hydroxyethylation of potato starch using ethylene oxide at temperatures between 293 and 318 K in aqueous starch slurries containing sodium sulfate. The rate of the hydroxyethylation of starch as a function of starch anion concentration (c

  20. Properties and applications of starch-converting enzymes of the α-amylase family

    Maarel, Marc J.E.C. van der; Veen, Bart van der; Uitdehaag, Joost C.M.; Leemhuis, Hans; Dijkhuizen, L.


    Starch is a major storage product of many economically important crops such as wheat, rice, maize, tapioca, and potato. A large-scale starch processing industry has emerged in the last century. In the past decades, we have seen a shift from the acid hydrolysis of starch to the use of starch-converti

  1. Properties and applications of starch-converting enzymes of the alpha-amylase family

    van der Maarel, MJEC; van der Veen, B; Uitdehaag, JCM; Leemhuis, H; Dijkhuizen, L


    Starch is a major storage product of many economically important crops such as wheat, rice, maize, tapioca, and potato. A large-scale starch processing industry has emerged in the last century. In the past decades, we have seen a shift from the acid hydrolysis of starch to the use of starch-converti

  2. Raw starch-degrading alpha-amylase from Bacillus aquimaris MKSC 6.2 : isolation and expression of the gene, bioinformatics and biochemical characterization of the recombinant enzyme

    Puspasari, F.; Radjasa, O. K.; Noer, A. S.; Nurachman, Z.; Syah, Y. M.; van der Maarel, M.; Dijkhuizen, L.; Janecek, S.; Natalia, D.; Janeček, Š.


    Aims The aims were to isolate a raw starchdegrading a-amylase gene baqA from Bacillus aquimaris MKSC 6.2, and to characterize the gene product through in silico study and its expression in Escherichia coli. Methods and Results A 1539 complete open reading frame of a starchdegrading a-amylase gene ba

  3. Influence of starch origin on rheological properties of concentrated aqueous solutions

    Stojanović Željko P.


    Full Text Available The rheological properties of corn and potato starch concentrated aqueous solutions were investigated at 25ºC. The starches were previously dispersed in water and the solutions were obtained by heating of dispersions at 115-120ºC for 20 minutes. The solutions of potato starch were transparent, while the corn starch solutions were opalescent. The results of dynamic mechanical measurements showed that the values of viscosity, h, storage modulus, G′, and loss modulus, G″, of the corn starch solutions increased with the storage time. This phenomenon was not observed for the potato starch solutions. It was assumed that the increase of h, G′ and G″ is the result of starch solutions retrogradation. The potato starch solutions retrogradation did not occur probably because of the phosphates presence. The viscosity of 2 mass % corn starch solution is less than the viscosity of 2 mass % potato starch solution. By increasing the concentration of corn starch solution the gel with elastic behavior was formed. The corn starch solutions formed gel as early as at 4 mass % concentration, while potato starch solutions achieved the gel state at the concentration of 5 mass %. The value of exponent m (G′ and G″ µ wm during the transition of potato starch solutions to gel is 0.414, which gives the fractal dimensions for corn starch of 2.10. The obtained value of fractal dimension corresponds to slow aggregation. The corn starch solutions with the starch concentrations higher than 4 mass % form weak gels. For these solutions the values of modulus in rubber plateau were determined. It was found that the modulus in rubber plateau increased with the concentration by the exponent of 4.36. Such high exponent value was obtained in the case when the tridimensional network is formed, i.e. when supermolecular structures like associates or crystal domains are formed.

  4. Green starch conversions : Studies on starch acetylation in densified CO2

    Muljana, Henky; Picchioni, Francesco; Heeres, Hero J.; Janssen, Leon P. B. M.


    The acetylation of potato starch with acetic anhydride (AAH) and sodium acetate (NaOAc) as catalyst in densified CO2 was explored in a batch reactor setup. The effects of process variables such as pressure (6-9.8 MPa), temperature (40-90 degrees C), AAH to starch ratio (2-5 mol/mol AGU), NaOAc to st

  5. Utilization of byproducts from potatoes and vegetables for value-added products; Perunan ja vihannesten sivuvirtojen arvokomponenttien hyoetykaeyttoe

    Ahokas, M.; Valimaa, A.-L.; Kankaala, A.; Lotjonen, T.; Virtanen, E.


    In this report, by-products are defined as the fractions produced in processing of potatoes and vegetables in addition to the main products. These by-products include peels, potato pulp, potato fruit juice, leftovers from cutting processes and under-sized potatoes left in the field. The amount of the by-products varies depending on the process. For example, in peeling processes the amount of by-products can be as much as 50-100% compared to that of the peeled product. The disposal of the by-products is strictly regulated by the national biowaste strategy, the landfill directive and the new waste legislation. For example, the landfill directive requires a gradual reduction in the amount of biodecomposable community waste. This means that in 2016, an maximum of 25% of the estimated biodecomposable community waste produced can be placed in landfill sites. Moreover, the EU aims at increasing the amount of the renewable traffic fuels to 10% by the year 2020. The utilization of the by-products in an effective and holistic way is not necessary only due to the tight legislative demands, but also n order to make the production economically profitable. For example, it is possible to separate from by-products of potatoes and vegetables commercially valuable biocomponents, such as starch, proteins and fiber, and to produce bioethanol and biogas in biorefinery plants. In the biorefinery plants, chemicals, biofuels and energy are produced sustainably using mechanical, chemical and biological processes. However, in a conventional refinery process usually only one component is utilized, for example potato starch. The North Ostrobothnia region is lacking the biorefinery that utilizes the by-products of potatoes and vegetables. This study was carried out in 2011-2012 by MTT Agrifood Research Finland Oulu. The objective was to develop a biorefinery concept in which by-products from potato and vegetables industry are manufactured to value-added products efficiently utilizing the

  6. Studies of the retrogradation process for various starch gels using Raman spectroscopy.

    Fechner, Petra M; Wartewig, Siegfried; Kleinebudde, Peter; Neubert, Reinhard H H


    The retrogradation of untreated wild-type starches (potato, maize, and wheat), waxy maize starches, and one pregelatinized, modified amylose-rich starch was investigated continuously using Raman spectroscopy. The method detects conformational changes due to the multi-stage retrogradation, the rate of which differs between the starches. The pregelatinized, modified amylose-rich starch shows all stages of retrogradation in the course of its Raman spectra. In comparison to amylose, the retrogradation of amylopectin is faster at the beginning of the measurements and slower in the later stages. The untreated starches can be ranked in the order of their rate of retrogradation as follows: potato>maize>wheat.



    Potato branching enzyme, a key enzyme in the biosynthesis of starch, was localized in amyloplasts in starch-storage cells of potato (Solanum tuberosum L) with the use of immunogold electron microscopy. Branching enzyme was found in the amyloplast stroma, concentrated at the interface of the stroma

  8. The potato amylase inhibitor gene SbAI regulates cold-induced sweetening in potato tubers by modulating amylase activity.

    Zhang, Huiling; Liu, Jun; Hou, Juan; Yao, Ying; Lin, Yuan; Ou, Yongbin; Song, Botao; Xie, Conghua


    Potato cold-induced sweetening (CIS) is critical for the postharvest quality of potato tubers. Starch degradation is considered to be one of the key pathways in the CIS process. However, the functions of the genes that encode enzymes related to starch degradation in CIS and the activity regulation of these enzymes have received less attention. A potato amylase inhibitor gene known as SbAI was cloned from the wild potato species Solanum berthaultii. This genetic transformation confirmed that in contrast to the SbAI suppression in CIS-resistant potatoes, overexpressing SbAI in CIS-sensitive potatoes resulted in less amylase activity and a lower rate of starch degradation accompanied by a lower reducing sugar (RS) content in cold-stored tubers. This finding suggested that the SbAI gene may play crucial roles in potato CIS by modulating the amylase activity. Further investigations indicated that pairwise protein-protein interactions occurred between SbAI and α-amylase StAmy23, β-amylases StBAM1 and StBAM9. SbAI could inhibit the activities of both α-amylase and β-amylase in potato tubers primarily by repressing StAmy23 and StBAM1, respectively. These findings provide the first evidence that SbAI is a key regulator of the amylases that confer starch degradation and RS accumulation in cold-stored potato tubers.


    Elena Corina Popescu


    Full Text Available Maize, rice, wheat and potato are the main sources of starches which differ significantly in composition, morphology,thermal, rheological and retrogradation properties. Starch has unique thermal properties and functionality that havepermitted its wide use in food products and industrial applications.The structure of the starch granule results from the physical arrangement of amylose and amylopectin. Amylose contentof starches from different maize types ranged between 15.3% and 25.1%. Amylopectin is considered responsible for thecrystalline structure of starch granules.The morphological and physicochemical characteristics of maize starch are related to the enzymes involved in itsbiosynthesis.The surface of the starch granule plays a fundamental rôle as the first barrier to processes such as granule hydration,enzyme attack, and chemical reaction with modifying agents. Major parameters describing the solid surface are:specific surface area, total pore volume, mean pore radius (diameter and pore volume distribution in relation to poreradius (diameter.

  10. Effects of starches on the textural, rheological, and color properties of surimi-beef gels with microbial tranglutaminase.

    Zhang, Fenghui; Fang, Ling; Wang, Chenjie; Shi, Liu; Chang, Tong; Yang, Hong; Cui, Min


    In order to evaluate effects of starches (corn starch, potato starch, and tapioca starch) on the characteristics of surimi-beef gels with microbial transglutaminase, the cooking loss, gel strength, color and rheological properties of samples were investigated. Results demonstrated that starches gave negative effects on the cooking loss of surimi-beef gels. The gel with corn starch had the highest cooking loss while that with tapioca starch showed the lowest value. The gel with potato starch obtained the highest gel strength. During the sol-gel transitions, surimi-beef complexes with 3% corn starch exhibited the highest storage modulus value, while that with 3% tapioca starch had the lowest one. The addition of starch caused the increase of L* values of surimi-beef gels. Results showed that the excessive amount of starch resulted in the decrease in gel strength of surimi-beef gels.

  11. Physicochemical properties of maca starch.

    Zhang, Ling; Li, Guantian; Wang, Sunan; Yao, Weirong; Zhu, Fan


    Maca (Lepidium meyenii Walpers) is gaining research attention due to its unique bioactive properties. Starch is a major component of maca roots, thus representing a novel starch source. In this study, the properties of three maca starches (yellow, purple and black) were compared with commercially maize, cassava, and potato starches. The starch granule sizes ranged from 9.0 to 9.6μm, and the granules were irregularly oval. All the maca starches presented B-type X-ray diffraction patterns, with the relative degree of crystallinity ranging from 22.2 to 24.3%. The apparent amylose contents ranged from 21.0 to 21.3%. The onset gelatinization temperatures ranged from 47.1 to 47.5°C as indicated by differential scanning calorimetry. Significant differences were observed in the pasting properties and textural parameters among all of the studied starches. These characteristics suggest the utility of native maca starch in products subjected to low temperatures during food processing and other industrial applications.

  12. Sugarcane starch: quantitative determination and characterization

    Joelise de Alencar Figueira


    Full Text Available Starch is found in sugarcane as a storage polysaccharide. Starch concentrations vary widely depending on the country, variety, developmental stage, and growth conditions. The purpose of this study was to determine the starch content in different varieties of sugarcane, between May and November 2007, and some characteristics of sugarcane starch such as structure and granules size; gelatinization temperature; starch solution filterability; and susceptibility to glucoamylase, pullulanase, and commercial bacterial and fungal α-amylase enzymes. Susceptibility to debranching amylolytic isoamylase enzyme from Flavobacterium sp. was also tested. Sugarcane starch had spherical shape with a diameter of 1-3 µm. Sugarcane starch formed complexes with iodine, which showed greater absorption in the range of 540 to 620 nm. Sugarcane starch showed higher susceptibility to glucoamylase compared to that of waxy maize, cassava, and potato starch. Sugarcane starch also showed susceptibility to debranching amylolytic pullulanases similar to that of waxy rice starch. It also showed susceptibility to α-amylase from Bacillus subtilis, Bacillus licheniformis, and Aspergillus oryzae similar to that of the other tested starches producing glucose, maltose, maltotriose, maltotetraose, maltopentose and limit α- dextrin.

  13. Maximal release of highly bifidogenic soluble dietary fibers from industrial potato pulp by minimal enzymatic treatment

    Thomassen, Lise Vestergaard; Vigsnæs, Louise Kristine; Licht, Tine Rask


    Potato pulp is a poorly utilized, high-volume co-processing product resulting from industrial potato starch manufacturing. Potato pulp mainly consists of the tuber plant cell wall material and is particularly rich in pectin, notably galactan branched rhamnogalacturonan I type pectin which has...

  14. Dissection of the major late blight resistance cluster on potato linkage group IV

    Lokossou, A.A.


    Potato is consumed worldwide and represents the fourth most important staple food crop after rice and wheat. Potato cultivars display a large variety of color, shape, taste, cooking properties and starch content but are all derived from the same species; Solanum tuberosum. Potato breeding is an econ

  15. 不同淀粉糊化及凝胶特性与粉条品质的关系%Relationship between gelatinization and gel properties of different starch and their noodles

    廖卢艳; 吴卫国


    materials are from mung bean, sweet potato, potato, rice, and corn. The results showed that these five starch noodles have different qualities. By evaluating the starch noodles cooking and texture qualities, the mung bean resulted as the best, followed by the potato and sweet potato, and rice and corn were the worst. The results also indicated that starch gelatinization properties and their noodles have a significant correlation. These influential parameters were related according to the p value:peak viscosity>valley viscosity value>attenuation value>setback viscosity, final viscosity. In addition, starch gel hardness, elasticity, viscosity, and chewiness have a bigger influence on the quality of starch noodles, according to the degree of significant size value (p) in turn is:hardness>viscosity>chewiness>elasticity. A significant correlation was seen between the quality of starch noodles and the parameters of valley viscosity, setback, resilience, chewiness, and sticky. This was considered an important way of predicting the qualities of starch noodles and can be regarded as the major indexes for starch noodle raw material selection. These research results can provide a sensitive method for monitoring the quality of starch for starch noodles production and explore a convenient method for evaluating the qualities of starch noodles. In doing so, this can provide the theory basis for starch noodles’ qualities improvement.%为了研究粉条加工过程中原料淀粉的糊化及凝胶特性对粉条品质的影响,该文对绿豆、红薯、马铃薯、大米和玉米等5种原料淀粉的糊化凝胶特性及其粉条品质进行了测定,并对淀粉糊化凝胶特性与淀粉粉条品质之间的关系进行探讨。结果表明:5种淀粉原料所制的粉条中,绿豆粉条的品质是较好,其次就是马铃薯粉条和红薯粉条,大米粉条和玉米粉条的品质较差;淀粉的糊化特性与粉条品质之间具有显著相关性,按显著程度

  16. Structural characterization of Peruvian carrot (Arracacia xanthorrhiza) starch and the effect of annealing on its semicrystalline structure.

    Rocha, Thais S; Cunha, Verena A G; Jane, Jay-Lin; Franco, Celia M L


    Structural characteristics of native and annealed Peruvian carrot (Arracacia xanthorrhiza) starches were determined and compared to those of cassava and potato starches. Peruvian carrot starch presented round and irregular shaped granules, low amylose content and B-type X-ray pattern. Amylopectin of this starch contained a large proportion of long (DP > 37) and short (DP 6-12) branched chains. These last ones may contribute to its low gelatinization temperature. After annealing, the gelatinization temperatures of all starches increased, but the ΔH and the crystallinity increased only in Peruvian carrot and potato starches. The annealing process promoted a higher exposure of Peruvian carrot amylose molecules, which were more quickly attacked by enzymes, whereas amylopectin molecules became more resistant to hydrolysis. Peruvian carrot starch had structural characteristics that differed from those of cassava and potato starches. Annealing affected the semicrystalline structure of this starch, enhancing its crystallinity, mainly due to a better interaction between amylopectin chains.

  17. Cassava, yam, sweet potato and ñampi starch: functional properties and possible applications in the food industry. Harinas y almidones de yuca, ñame, camote y ñampí: propiedades funcionales y posibles aplicaciones en la industria alimentaria.

    Pedro Vargas Aguilar


    Full Text Available A technical review was conducted to related physical and chemical properties of flours and starches from cassava, yams, taro and sweet potato. Amyloseamylopectin content, viscosity, nutritional value and fiber, were studied to relate them with starch functional properties. A relationship was obtained between amylose-amylopectin, viscosity and fiber content with the digestibility of those starches and the glycemic index values. The use of fermentation to enhance the nutritional value of these starches is known. Starch fermentation allows the production of gluten-free bread and energy drinks as an option to diversify products. It was also observed the relationship between the starch viscosity and the fat absorption in fried foods.Se realizó una revisión de las características fisicoquímicas de las harinas y almidones de yuca, ñame, ñampí y camote, tales como el contenido de amilosa-amilopectina, la viscosidad, el valor nutricional y la fibra, con el fin de relacionarlas con sus propiedades funcionales y técnico-funcionales. Se obtuvo una relación entre el contenido de amilosa-amilopectina, viscosidad y contenido de fibra en la digestibilidad de estos almidones y los valores de índice glicémico. Se encontró que es posible introducir modificaciones por medio de la fermentación para mejorar el valor funcional de estos almidones. La fermentación permite elaborar pan sin gluten y bebidas energéticas como nuevas opciones de productos. También se encontró que existe una relación entre la viscosidad de los almidones y la disminución de absorción de la grasa en frituras.

  18. Sensory and rheological properties of transgenically and chemically modified starch ingredients as evaluated in a food product model

    Ahmt, T.; Wischmann, Bente; Blennow, A.


    Starches derived from five genetically modified potato lines, two chemically modified potato starches and two native starches from potato and maize were subjected to physical and chemical analyses and their functionality evaluated in a milk-based food product model. The transgenic starches were...... gels with a higher tendency to retrograde and a low freeze/thaw stability as compared to starches with shorter amylopectin chains and lower phosphorous content. The textural properties of the food product model prepared from genetically and chemically modified starches were characterised by sensory...... and rheological analyses. To clearly visualise the effects of the modifications, data was evaluated by radar plots and multiple regression analysis (chemometrics). Genetically modified potato starches with longer amylopectin chains and increased phosphorous content gave a more gelled and a shorter texture...

  19. Natural diversity of potato (Solanum tuberosum) invertases


    Background Invertases are ubiquitous enzymes that irreversibly cleave sucrose into fructose and glucose. Plant invertases play important roles in carbohydrate metabolism, plant development, and biotic and abiotic stress responses. In potato (Solanum tuberosum), invertases are involved in 'cold-induced sweetening' of tubers, an adaptive response to cold stress, which negatively affects the quality of potato chips and French fries. Linkage and association studies have identified quantitative trait loci (QTL) for tuber sugar content and chip quality that colocalize with three independent potato invertase loci, which together encode five invertase genes. The role of natural allelic variation of these genes in controlling the variation of tuber sugar content in different genotypes is unknown. Results For functional studies on natural variants of five potato invertase genes we cloned and sequenced 193 full-length cDNAs from six heterozygous individuals (three tetraploid and three diploid). Eleven, thirteen, ten, twelve and nine different cDNA alleles were obtained for the genes Pain-1, InvGE, InvGF, InvCD141 and InvCD111, respectively. Allelic cDNA sequences differed from each other by 4 to 9%, and most were genotype specific. Additional variation was identified by single nucleotide polymorphism (SNP) analysis in an association-mapping population of 219 tetraploid individuals. Haplotype modeling revealed two to three major haplotypes besides a larger number of minor frequency haplotypes. cDNA alleles associated with chip quality, tuber starch content and starch yield were identified. Conclusions Very high natural allelic variation was uncovered in a set of five potato invertase genes. This variability is a consequence of the cultivated potato's reproductive biology. Some of the structural variation found might underlie functional variation that influences important agronomic traits such as tuber sugar content. The associations found between specific invertase alleles and

  20. Starch gelatinization.

    Ratnayake, Wajira S; Jackson, David S


    Starch occurs as highly organized structures, known as starch granules. Starch has unique thermal properties and functionality that have permitted its wide use in food products and industrial applications. When heated in water, starch undergoes a transition process, during which the granules break down into a mixture of polymers-in-solution, known as gelatinization. The sequence of structural transformations that the starch granule undergoes during this order-to-disorder transition has been extensively researched. None of the published starch gelatinization theories can fully and adequately explain the exact mechanism of sequential structural changes that starch granules undergo during gelatinization. This chapter analyzes several published theories and summarizes our current understanding of the starch gelatinization process.

  1. Understanding the role of plasticisers in spray-dried starch

    Niazi, Muhammad Bilal Khan; Zijlstra, Mark; Broekhuis, Antonius A.


    Amorphous thermoplastic starch (TPS) films were produced by compression moulding of solution spray-dried TPS powder and by direct solution casting. Oxidised potato starch was used as a feedstock for production of plasticised formulations containing glycerol or urea, or their combinations with maltod

  2. Superheated starch: A novel approach towards spreadable particle gels

    Steeneken, P.A.M.; Woortman, A.J.J.


    When aqueous potato starch suspensions were heated into the solution state and cooled, spreadable particle gels were obtained with a spherulite morphology and a cream-like texture. This so-called superheated starch (SHS) exhibits more effective gelling properties than maltodextrin, which is

  3. Unique features of several microbial α-amylases active on soluble and native starch

    Sarian, Fean Davisunjaya


    Starch is the main energy store of major agricultural crops such as corn, potato, rice and wheat. Various amylase type enzymes are used to convert cooked starch to glucose that goes into bioethanol fermentation. Only a few amylase type enzymes have been described that can act on the starch granule i

  4. Properties and applications of starch-converting enzymes of the alpha-amylase family

    van der Maarel, MJEC; van der Veen, B; Uitdehaag, JCM; Leemhuis, H; Dijkhuizen, L


    Starch is a major storage product of many economically important crops such as wheat, rice, maize, tapioca, and potato. A large-scale starch processing industry has emerged in the last century. In the past decades, we have seen a shift from the acid hydrolysis of starch to the use of

  5. Determination of Sulful Dioxide Residues in the Starch Noodles Including Sweet Potato and Tomato Juice by Distillation and Titration Employing Iodine%蒸馏-碘滴定法测定红薯蕃茄粉丝中二氧化硫残留



    A method for determination of sulful dioxide residues in the starch noodles including sweet potato and tomato juice was introduced,by using the method of distillation and titration employing iodine to determine sulful dioxide residues.The accuracy was 1.3% to 1.87%.The result showed that the sulful dioxide residues in the noodles can be fast determined by distillation and titration employing iodine.The operation was easy operation,and the sensitivity and the accuracy were high.The method can control the quality of sulful dioxide residues in the starch noodles including sweet potato and tomato juice.%采用蒸馏-碘滴定法测定了红薯蕃茄粉丝中二氧化硫残留,精密度在1.3%~1.87%之间。结果表明:粉丝中微量二氧化硫的残留量可以用蒸馏-碘滴定法快速检测。此法操作简单、灵敏度高、重现性好。可用于粉丝中二氧化硫质量控制。

  6. Study on Influences of Different Starch on Egg White Paste%不同淀粉对蛋清浆的影响研究



    Objective] The aim was to explore the suitable sizing process parameters of different materials in egg white paste. [Method] The ratio of egg white paste under the certain conditions was obtained, through the study on influences of three kinds of common starch, such as egg white pulp corn, sweet potato, potato and modified starch on sizing process. [Result] The results showed that on the amount of starch, with modified starch dosage at least. In terms of sizing overall effect, with corn starch and potato starch were more appropriate. Sweet potato starch modulation of egg white paste slightly more water added, but from the point of trial, for a small amount of raw materials made of egg white paste, with water content increasing, the slurry performance was declining, therefore, should be few add or not add water. [Conclusion]Through the experiments, the egg white paste suitable shape index and the optimum temperature lubricating oil were concluded.%[目的]探讨蛋清浆合适的不同原料上浆工艺参数。[方法]通过研究蛋清浆中玉米、甘薯、马铃薯3种常见淀粉及变性淀粉对上浆工艺的影响,得出了在一定条件下蛋清浆的用量之比。[结果]结果表明,在淀粉的用量方面,以变性淀粉用量最少;就上浆总体效果而言,以玉米淀粉和马铃薯淀粉较为适宜。甘薯淀粉调制的蛋清浆加水量略多一些,但从试验来看,对于少量原料制作的蛋清浆,随着加水量的增多,浆液性能呈下降趋势,故宜少加或不加水。[结论]通过试验,得出了蛋清浆合适的成型指标及滑油的适宜温度。

  7. Characterisation, in vitro digestibility and expected glycemic index of commercial starches as uncooked ingredients.

    Romano, Annalisa; Mackie, Alan; Farina, Federica; Aponte, Maria; Sarghini, Fabrizio; Masi, Paolo


    In this study native starches as ingredients (corn, rice, wheat, tapioca and potato) were characterized for microstructure, physicochemical, functional and thermal properties, in vitro digestibility and glycemic index. There was a significant variation in the granule shape and size distribution of the starches. Particle size monomodal (corn, tapioca, potato) and bimodal (rice, wheat) distribution was observed amongst the starches. The potato starch showed the biggest size granules while the rice showed the smallest. The examined properties and nutritional characteristics of starches were significantly different. Thermal properties were studied using Differential Scanning Calorimeter (DSC). DSC results showed that the transition temperatures (58.8-78.7 °C) and enthalpies of gelatinization (2.3-8.2 J/g) of the starches appeared to be greatly influenced by microstructure and chemical composition (e.g. resistant starch). Nutritional properties such as slowly digestible starch and expected glycemic index values followed the order: rice > wheat > tapioca > corn > potato. In particular, the highest resistant starch was recorded for potato starch.

  8. 马铃薯废弃物的资源化利用%Utilization of potato processing waste

    安志刚; 韩黎明; 刘玲玲; 童丹; 孙永军


    The potato processing waste which produced from the potato harvesting and potato processing has a serious impact on the environment.By studying scientific articles,this study discussed the technology on utilization of potato waste in four aspects,including potato stems and leaves,potato-starch wastewater,potato-starch residue and potato-peel waste.Potato waste has a good potential to be used due to its rich compounds.%通过检索大量科学文献,从马铃薯的茎叶、废水、废渣、废皮4个方面论述了资源化利用马铃薯废弃物的技术.马铃薯废弃物有效成分丰富,具有良好的开发利用价值.

  9. Change of Starch,Reducing Sugar and Amylase Activity of Potato during Storage in the Caves Warehouse%山体库贮藏马铃薯淀粉、还原糖含量及淀粉酶活性的变化

    张勇; 高海宁; 王恩军; 王兴德; 李红; 李彩霞


    为探讨甘肃省民乐县山体库贮藏对马铃薯品质的影响.对9个马铃薯品种不同贮藏时期淀粉、还原糖含量以及淀粉酶活性进行分析测定.结果表明:随着贮藏期的延长,大多数品种的淀粉含量表现为升→降→升→降,还原糖含量表现为升→降,淀粉酶活性表现为升→降→升→降;2月份是一个临界贮藏时期,淀粉含量降低到最低(12.68%~22.47%),还原糖含量达到最高点(0.43%~2.41%),淀粉酶活性降低到最低点(0.43~0.87mg/(g·min)).山体库有利于马铃薯的贮藏;'青薯6号'和'同薯23号'适合做菜 用型品种,'大西洋'、'夏波蒂'和'LK-99'适合做生产加工型品种,为了保证品质,最佳的加工时间在次年2月之前完成;淀粉酶活性和淀粉含量之间存在负相关,与还原糖之间存在正相关,淀粉含量和还原糖含量之间存在负相关,淀粉含量和还原糖含量之间处于动态平衡状态.%In order to explore the caves warehouse storage effect of quality of potato in Minle County, Gansu Province. We collected nine cultivars of potatoes from the Minle County, Gansu Province to evaluate the starch,reducing sugar content and amylase activity which stored at different storage periods. The results indicate that with the storage period developed, the starch content of the most potatoes were showed increase-decrease-increase-decrease, reducing sugar contents were showed increase-decrease, and amylase activity were showed increase-decrease-increase-decrease. During January to February, the lowest temperature in a year, the starch content and amylase activity reached their minimum level (12.68%-22.47%)and (0.43-0.87 mg/(g· min), respectively, but the reducing sugar achieved their maximum level (0.43%-2.41%). The caves warehouse was of benefit to storage of potato. Pearson correlation matrix analysis showed that, reducing sugar content and amylase activity negatively correlated with starch, but amylase


    陈金发; 谢永红; 朱海峰; 王姗镒


    试验研究了在改装UASB(MUASB)装置中培养好氧颗粒污泥及其处理生活污水和高浓度马铃薯深加工废液的效果。试验结果表明:可以在4d内快速培养出好氧颗粒污泥。成熟的颗粒污泥平均直径达2mm。当马铃薯深加工废液浓度P(COD)、P(NH4^+-N)、P(TP)平均分别为12817.16,106.10,26.37mg/L时,处理效果分别超过64%、63%和67%。利用共聚焦激光扫描显微镜观测颗粒污泥,虽然球菌主要形成了一个相对凝结的区域,但是在颗粒污泥的边缘区域出现许多丝状菌。α多糖主要分布在颗粒的核心。在颗粒中还发现少量的β多糖和无生命的细胞。%Formation and performances of aerobic granule sludge were investigated in a modified UASB (MUASB) reactor treating both landfill leachate and domestic wastewaters. Results showed that granules could be formed from flocculating sludge in MUASB within 4 d. Granules had an average diameter of 2 mm during steady operation. When potato starch waste water's COD, ammonia nitrogen and TP was 12 817. 16,106.10 and 26.37 mg/L respectively, their treating effectiveness was over 64% , 63% and 67% respectively. As for mature granules, confocal laser scanning microscopy (CLSM) observation revealed that a lot of filamentous bacteria were presented in the fringe region, while cocci were predominant and formed a relatively condensed region in the granule interior. The a-polysaccharides were mainly distributed in the core of granules. Few β- polysaccharides and dead cells were detected in the granules.

  11. Screening of bioflocculant-producing strains and optimization of its nutritional conditions by using potato starch wastewater%马铃薯淀粉废水生产微生物絮凝剂菌株筛选及其营养条件优化

    颜东方; 贠建民


    In recent years, researchers have paid more and more attention to bioflocculants in waste disposal study. Because the bioflocculants were usually biodegradable and their degradation products were harmless to environment, so the bioflocculants have a good application prospects. However, it was not widely used to practical application till now, because of its low flocculation ability of producing strain and high cost. One measure to decrease the cost associated with the production on industrial scale was to employ low-cost substrates. To develop a novel bioflocculant, a novel technology of producing bioflocculant was studied through screening biofloccuant-producing microorganism which could utilize potato starch wastewater as substrate, then its nutritional conditions was optimized. Moreover, the study would provide a new way for potato starch wastewater reutilization. In the study, 100 strains were isolated from activated sludge. Each strain was cultured separately in either nutrient agar or potato dextrose agar as primarily screening flocculant-producing strain medium. The flocculation rate of fermentation broth against Kaolin clay suspension was used as the evaluation index, 13 bioflocculant-producing strains were screened. According to the ability of strains fermenting potato starch wastewater and producing flocculants, one high yield strain was obtained, named as F5, which was identified as Candida anglica by 26SrDNA analysis. The nutritional contditons that C. anglica fermented potato starch wastewater to produce bioflocculant were optimized through single factor test and the orthogonal test. The results showed that under the conditions of pH value 5.6, inoculum size 10%( volume fraction), 150 r/min and 28 for℃48 h, the best nutritional compositions were: 1 mL/100 mL glycerin as adding carbon sources, 0.05 g/100 mL (NH4)2SO4 as nitrogen source, 0.1 g/100 mL MgCl2 and 0.1 g/100 mL KH2PO4. The test showed that C. anglica could grow well in non

  12. Sixth taste – starch taste?

    Zygmunt Zdrojewicz


    Full Text Available Scientists from Oregon State University, USA, came up with the newest theory of the sixth taste – starch taste that might soon join the basic five tastes. This argument is supported by studies done on both animals and humans, the results of which seem to indicate the existence of separate receptors for starch taste, others than for sweet taste. Starch is a glucose homopolymer that forms an α-glucoside chain called glucosan or glucan. This polysaccharide constitutes the most important source of carbohydrates in food. It can be found in groats, potatoes, legumes, grains, manioc and corn. Apart from its presence in food, starch is also used in textile, pharmaceutical, cosmetic and stationery industries as well as in glue production. This polysaccharide is made of an unbranched helical structure – amylose (15–20%, and a structure that forms branched chains – amylopectin (80–85%. The starch structure, degree of its crystallisation or hydration as well as its availability determine the speed of food-contained starch hydrolysis by amylase. So far, starch has been considered tasteless, but the newest report shows that for people of different origins it is associated with various aliments specific for each culture. Apart from a number of scientific experiments using sweet taste inhibitors, the existence of the sixth taste is also confirmed by molecular studies. However, in order to officially include starch taste to the basic human tastes, it must fulfil certain criteria. The aim of the study is to present contemporary views on starch.

  13. Cassava starch in the Brazilian food industry

    Ivo Mottin Demiate


    Full Text Available Cassava starch is a valued raw material for producing many kinds of modified starches for food applications. Its physicochemical properties, as well as its availability, have made it an interesting and challenging ingredient for the food industry. In the present work, food grade modified cassava starches were purchased from producers and analyzed for selected physicochemical characteristics. Samples of sour cassava starch were included, as well as one sample of native cassava starch. Results showed that almost all modified starches were resistant to syneresis, produced pastes more stable to stirred cooking, and some of them were difficult to cook. The sour cassava starches presented high acidity and resulted in clear and unstable pastes during stirred cooking, susceptible to syneresis.

  14. 不同马铃薯品种的不同加工产品适宜性评价%Suitability evaluation of different potato cultivars for processing products

    杨炳南; 张小燕; 赵凤敏; 杨延辰; 刘威; 李树君


    , total sugar, starch, moisture, dry matter, ash, total soluble solids, vitamin C, protein, fat and crude fiber of raw potatoes were analyzed according to China national or industrial standards. Analysis of variance revealed significant differences and great variation among most of indicators. Three kinds of products including potato chips, French fries and potato flakes were processed using 44 cultivars collected respectively. The quality indicators of processed products were also tested in the laboratory. For potato chips, four indicators including sensory evaluation, protein, crispness and Hunter whiteness were tested. For French fries, four indicators including sensory evaluation, protein, hardness and Hunter whiteness were tested. For potato flakes, four indicators including sensory evaluation, protein, viscosity and free starch ratio were tested. Analysis of variance also revealed great variation among indicators of three kinds of processed products. Using the maximum - minimum normalized method, multiple quality indicators of potato chips, French fries and potato flakes were calculated into a one-dimensional evaluation indicator in order to establish a representative model. Each comprehensive indicator had a significant correlation with four original indicators of processed products. With stepwise regression method, significant indicators of raw materials were selected to establish the model of processed products, while insignificant indicators were eliminated to reduce the redundancy of models. Based on three calculated comprehensive indicators and 14 indicators of raw materials, comprehensive quality evaluation models of potato chips, French fries and potato flakes were established respectively. The results showed that, the comprehensive quality of potato chips were remarkably influenced by the reducing sugar, ash, protein, eye number and total soluble solids of raw potatoes; the effect of potato chips' comprehensive quality evaluation model were: the coefficient

  15. Processing effects on susceptibility of starch to digestion in some dietary starch sources.

    Niba, Lorraine L


    Maize flour, potato flour, cocoyam flour, plantain flour, yam flour, and rice flour were assayed for starch digestibility by an established enzymatic procedure. These were either autoclaved, microwaved, or parboiled and then freeze-dried. Freeze-dried samples were stored for 10 days either below freezing or at ambient temperature. Parameters assessed were readily digestible starch (RDS), slowly digestible starch (SDS), and total starch (TS). Data was analyzed by t-test (P plantain flour to 68.4 g/100 g in rice flour. Autoclaving resulted in reduced TS levels insome flours. Moist heat processing and the post-process storage temperature therefore result in significant changes in starch susceptibility to enzymic digestion. This information will be useful in developing food processing and storage procedures that modify starch resistance to digestion in order to optimize its nutritional quality and to enhance the physiological benefits.

  16. Lysozyme uptake by oxidized starch polymer microgels

    Li, Y.; Vries, R.D.; Kleijn, M.; Slaghek, T.; Timmermans, J.; Stuart, M.C.; Norde, W.


    With the aim of determining suitable conditions for uptake and release of globular proteins on microgels, we studied the interaction between phosphated, highly cross-linked, negatively charged oxidized potato starch polymer (OPSP) microgel particles and lysozyme from hen eggs. Our microgel shows a

  17. Hydrolysis of native and heat-treated starches at sub-gelatinization temperature using granular starch hydrolyzing enzyme.

    Uthumporn, U; Shariffa, Y N; Karim, A A


    The effect of heat treatment below the gelatinization temperature on the susceptibility of corn, mung bean, sago, and potato starches towards granular starch hydrolysis (35°C) was investigated. Starches were hydrolyzed in granular state and after heat treatment (50°C for 30 min) by using granular starch hydrolyzing enzyme for 24 h. Hydrolyzed heat-treated starches showed a significant increase in the percentage of dextrose equivalent compared to native starches, respectively, with corn 53% to 56%, mung bean 36% to 47%, sago 15% to 26%, and potato 12% to 15%. Scanning electron microscopy micrographs showed the presence of more porous granules and surface erosion in heat-treated starch compared to native starch. X-ray analysis showed no changes but with sharper peaks for all the starches, suggested that hydrolysis occurred on the amorphous region. The amylose content and swelling power of heat-treated starches was markedly altered after hydrolysis. Evidently, this enzyme was able to hydrolyze granular starches and heat treatment before hydrolysis significantly increased the degree of hydrolysis.

  18. Understanding starch gelatinization: The phase diagram approach.

    Carlstedt, Jonas; Wojtasz, Joanna; Fyhr, Peter; Kocherbitov, Vitaly


    By constructing a detailed phase diagram for the potato starch-water system based on data from optical microscopy, synchrotron X-ray scattering and differential scanning calorimetry, we show that gelatinization can be interpreted in analogy with a eutectic transition. The phase rule explains why the temperature of the gelatinization transition (G) is independent on water content. Furthermore, the melting (M1) endotherm observed in DSC represents a liquidus line; the temperature for this event increases with increasing starch concentration. Both the lamellar spacing and the inter-helix distance were observed to decrease with increasing starch content for starch concentrations between approximately 65 wt% and 75 wt%, while the inter-helix distance continued decreasing upon further dehydration. Understanding starch gelatinization has been a longstanding challenge. The novel approach presented here shows interpretation of this phenomenon from a phase equilibria perspective. Copyright © 2015 Elsevier Ltd. All rights reserved.

  19. Potato Processing Industry By-products and Their Evaluation in Animal Nutrition

    Pınar Özdemir


    Full Text Available All around the world, particularly in developed countries, fresh potato consumption decreased while the consumption as fast food, snack and convenience food was increased. Potato processing industry has by-products such as cull potato, peel, pulp, and waste water. These by-products can be utilized for production of ethyl alcohol, single cell protein, microbial enzymes, lactic acid, organic fertilizer and bioethanol. The pulp obtained from the processing of potato for starch production can be considered as an energy source with starch content in animal nutrition. Recently, potato peel with the contents of bioactive compounds (chlorogenic, caffeic, gallic, protocatechuic acids and their antioxidant and antimicrobial effects have been intensely focused on. Conversion of by-products of potato processing industry into value-added products is economically important. It was reviewed here by-products of potato processing industry and their evaluation in animal nutrition.

  20. Effect of Starch Sources on the Release Rates of Herbicides Encapsulated


    The effects of starch sources on the behaviors of starch matrices and on the rates of herbicides released from the matrices were studied for slow release. The starches considered include native corn starch, wheat starch, potato starch and cassava starch. The matrices were prepared through encapsulating 2,4-dichlorophenoxyacetic or 2,4,5-trichlorophenoxyacetic acids as model herbicides with hot-gelatinized starch pastes. The encapsulation was evaluated in terms of herbicide content, swellability, encapsulation efficiency, and release rate. The results show that starch sources play an important role on the matrix behaviors and on release rates. The rate of 2,4-D released follows the order: wheat starch < potato starch < corn starch < cassava starch. And for the rate of 2,4,5-T, this order is nearly the same only with an exception that the late two kinds of starch are similar. It is also demonstrated that herbicides with different water solubility show different release rates, no matter what type of starch is used as the matrices.