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转谷氨酰胺酶的性质、制备及在食品加工中的应用 总被引:8,自引:0,他引:8
转谷氨酰胺酶是催化蛋白质分子之间交联的一种酶,对蛋白质的成胶能力、热稳定性、持水能力等功能特性有独特的改善作用。目前从微生物Streptoverticillium spp.中分离转谷氨酰胺酶和在食品工业中的实际应用都已经实现,因为从微生物制备可以实现大规模的工业化生产,成本低廉,为转谷氨酰胺酶在工业上的应用奠定了基础。现在转谷氨酰胺酶广泛地应用于海洋食品、面条/面团、奶制品、烘焙食品等食品加工领域,通过温和的酶反应可以明显地改善食品的硬度、弹性、热稳定性和持水能力。主要讨论了转谷氨酰胺酶的性质、分离和在食品加工中的应用。 相似文献
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转谷氨酰胺酶对乳蛋白质的改性作用 总被引:15,自引:3,他引:15
转谷氨酰胺酶是催化酰基转移反应的一种酶,可使蛋白质或多肽之间发生共价交联反应。本文介绍了转谷氨酰胺酶对牛乳蛋白质凝胶特性、乳化性、热稳定性、成膜性等特性的改性作用及其在乳品加工中的应用。 相似文献
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茂原链霉菌(Streptomyces mobaraensis)转谷氨酰胺酶酶原(pro-transglutaminase,pro-TG)在重组大肠杆菌中的表达量低,限制了其在食品、化妆品、纺织行业中的应用。通过对转谷氨酰胺酶酶原的基因序列进行密码子优化,降低其GC含量,提高了它在大肠杆菌中的表达水平,结果表明经优化后转谷氨酰胺酶原的表达量达到了优化前的4.4倍。为提高转谷氨酰胺酶的比活力,通过基于融合PCR的定点突变技术将转谷氨酰胺酶第二位的丝氨酸突变为脯氨酸,突变后转谷氨酰胺酶的比活力达到了突变前的1.26倍。上述研究结果表明,密码子优化及定点突变技术可以应用于优化转谷氨酰胺酶酶原在大肠杆菌中的表达。 相似文献
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转谷氨酰胺酶在食品加工中的应用 总被引:5,自引:0,他引:5
简要介绍了转谷氨酰胺酶的分类和性质,并从畜肉制品、乳制品、水产品、大豆蛋白制品、小麦粉制品和食品包装与保藏6个方面较为详细地介绍了其在食品加工中的应用情况。 相似文献
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在氨基葡萄糖存在的条件下,利用转谷氨酰胺酶(EC2.3.2.13)对酪蛋白进行糖基化交联修饰。以修饰酪蛋白产物中氨基葡萄糖的导入量为指标,采用单因素试验分别考察反应体系pH值、酶添加量、反应温度和时间对修饰反应的影响。优化后的适宜修饰条件为:酪蛋白底物质量浓度为30g/L,氨基葡萄糖添加量为3mol(每kg酪蛋白中)、pH值为7.5、酶添加量为10kU(每kg酪蛋白中)、反应温度为37℃、时间4h。与酪蛋白和转谷氨酰胺酶促交联的酪蛋白相比,修饰酪蛋白产物的乳化性质和胶凝性质得到显著改善,并且体外消化性能未受到影响,表明转谷氨酰胺酶催化的糖基化交联修饰可以用于改善酪蛋白的这些功能性质。 相似文献
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Shu-Juan Jiang 《International Journal of Food Properties》2013,16(6):1286-1299
Microbial transglutaminase was applied as a biocatalyst and glucosamine as an acyl acceptor to modify casein by cross-linking and glucosamine conjugation. Electrophoretic analysis revealed that transglutaminase-induced cross-linking and glucosamine conjugation occurred simultaneously during reaction, and some polymers of glycoproteins with higher molecular weights were formed in the modified casein product prepared. HPLC analysis demonstrated that about 1.2 mol of glucosamine was conjugated to 1 mol of casein, under the preparation conditions as follows: casein concentration of 3% (w/v), molar ratio of acyl donor in casein to glucosamine acceptor of 1:3, transglutaminase addition level of 10 U/g casein, reaction temperature of 37°C, and reaction time of 4 h. The evaluation results also showed that the surface hydrophobicity of the modified casein product decreased. The emulsifying activity index and emulsifying stability index of the modified casein product were 100.9 m2/g and 84.3%, about 12 and 20% higher than that of original casein. The digestibility in vitro of the modified casein product was the same as that of original casein or had an increase of 9.8%. Meanwhile, cross-linking of casein by transglutaminase in the absence of glucosamine showed adverse impact on the emulsifying properties of the cross-linked casein prepared. The new modification method developed might have the potential as an effective approach to improve the functional properties of food proteins. 相似文献
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Yi-Ning Zhang 《International Journal of Food Properties》2013,16(6):1257-1270
A microbial transglutaminase was used to cross-link soybean protein isolates in the presence of gelatin to prepare a cross-linked composite soybean protein-gelatin. Cross-linking conditions, such as total proteins, the ratio of soybean protein isolates to gelatin, and original pH, were fixed at 5% (w/v), 4:1 (w/w), and 7.5, respectively. The 4-hydroxyproline content in the modified product was measured and used as an index to select suitable transglutaminase addition, reaction temperature, and time by single factor experiments, which were found to be 20 U/g proteins, 40°C, and 2 h, respectively. Under the identified conditions, a modified product with 4-hydroxyproline content of about 36 mg/g proteins was prepared, and its functional properties were evaluated. SDS-PAGE analysis showed that several protein polymers existed in the modified product. Compared to the original soybean protein isolates or a cross-linked soybean protein isolates, the modified product had a better emulsifying stability and water holding capacity but a poor enzymatic digestibility in vitro, emulsifying activity and oil binding capacity; meanwhile, the dispersions formed by the modified product exhibited the highest apparent viscosity, storage modulus, and viscous modulus. 相似文献
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《Food additives & contaminants. Part A, Chemistry, analysis, control, exposure & risk assessment》2013,30(9):1364-1373
Transglutaminase is an enzyme that can be used to cross-link pieces of meat, fish or meat products. The resulting product gives the optical impression of an intact chunk of meat. The usage of transglutaminase as a food additive is permitted in some countries. However, its utilisation has to be declared to ensure transparency for consumers. This paper describes two orthogonal analytical methods suited for the detection of technological relevant transglutaminase concentrations (around 25?mg pure enzyme in 1?kg of product) in meat and meat products. The mass spectrometry-based approach relies on a previous digestion with Achromobacter lyticus protease and LC-MS/MS separation and detection. Sufficient selectivity was obtained by monitoring four different peptides. The orthogonal (complementary and independent), ELISA-based approach relies on two commercially available bacterial transglutaminase-specific antibodies, combined to a sandwich ELISA. The two methods were tested by analysing some 60 samples obtained from the market. 相似文献
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Kaufmann A Köppel R Widmer M 《Food additives & contaminants. Part A, Chemistry, analysis, control, exposure & risk assessment》2012,29(9):1364-1373
Transglutaminase is an enzyme that can be used to cross-link pieces of meat, fish or meat products. The resulting product gives the optical impression of an intact chunk of meat. The usage of transglutaminase as a food additive is permitted in some countries. However, its utilisation has to be declared to ensure transparency for consumers. This paper describes two orthogonal analytical methods suited for the detection of technological relevant transglutaminase concentrations (around 25?mg pure enzyme in 1?kg of product) in meat and meat products. The mass spectrometry-based approach relies on a previous digestion with Achromobacter lyticus protease and LC-MS/MS separation and detection. Sufficient selectivity was obtained by monitoring four different peptides. The orthogonal (complementary and independent), ELISA-based approach relies on two commercially available bacterial transglutaminase-specific antibodies, combined to a sandwich ELISA. The two methods were tested by analysing some 60 samples obtained from the market. 相似文献
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Erfan Danesh Mostafa Goudarzi Hossein Jooyandeh 《Sensing and Instrumentation for Food Quality and Safety》2018,12(4):2416-2425
The effects of transglutaminase treatment (0–2 units/g milk protein) on the chemical composition, textural characteristics, proteolysis and yield of reduced-fat Iranian white cheese (milk fat: 0.4–1.4% w/w) incorporated with whey proteins (0–6 g/L milk) were investigated. Enzyme-mediated inclusion of whey proteins in the reduced-fat cheese caused a noticeable increase in moisture to protein (M:P) ratio with concomitant decease in the hardness rheological parameters of fracture stress and Young’s and storage (G’) moduli. However, increase in concentrations of whey proteins or/and transglutaminase enzyme above a critical level led to formation of a cheese matrix with lower moisture content and greater values of hardness indices. Whey protein addition and transglutaminase treatment resulted in the same trends of changes in proteolysis rate and cheese yield as in cheese softness. Response surface method (RSM) suggested that the enzymatic incorporation of 4.2 g deliberately added whey proteins to 1 L of milk (1.04% w/w fat) into the cheese matrix using 0.833 unit transglutaminase per gram milk protein would provide a reduced-fat product with the softest texture and the highest yield. The scanning electron micrographs showed formation of honeycomb structures in the protein matrix of the reduced-fat sample with optimum formulation. 相似文献
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Jasim S Al‐Saadi Khalida A. Shaker Zeynep Ustunol 《International Journal of Dairy Technology》2014,67(3):420-426
The effect of heat, transglutaminase and combination of heat and transglutaminase treatments on the solubility of films prepared from goat milk casein, goat milk whey proteins and whole goat milk proteins was investigated. Goat milk casein films were less soluble when treated with transglutaminase and combination of heat with transglutaminase compare with heat‐treated caseins alone. Heat treatment was more effective at decreasing the solubility of whey protein films. SDS‐PAGE patterns demonstrated that goat milk caseins were better cross‐linked by transglutaminase, whereas whey proteins were better cross‐linked by heat. The extent of cross‐linking was further enhanced when a combination of heat and transglutaminase was used. 相似文献