玉米谷蛋白功能性质研究

该研究对谷蛋白功能性质进行测定,并与大豆分离蛋白相关性质进行比较,结果表明:玉米谷蛋白具有良好吸水性、持油性、湿润性、凝胶性;但持水性较差,乳化能力略低于大豆分离蛋白;并介绍玉米谷蛋白功能性质及其在食品中应用。     

大豆分离蛋白的凝胶性及其应用的研究进展

大豆分离蛋白是一种廉价的蛋白质资源,同时还具有多种功能性,凝胶性就是大豆分离蛋白重要的功能性质之一.为表明大豆分离蛋白凝胶性在食品加工中的重要作用,对大豆分离蛋白的凝胶性进行调查研究,概述了大豆分离蛋白凝胶的形成机理,并总结出影响大豆分离蛋白凝胶性能的因素.包括:加热温度、加热时间、离子强度、pH值和酶.此外,还介绍了大豆分离蛋白因其具有良好凝胶性和高蛋白含量的特点,而在食品加工行业中得到的广泛应用.     

不同干燥方法对大豆分离蛋白功能性质的影响

采用离心喷雾干燥、真空冷冻干燥、热风干燥、微波干燥对大豆分离蛋白进行干燥，研究干燥后的大豆分离蛋白的功能性质。结果表明：微波干燥的大豆分离蛋白粘度较大，而乳化性、吸水性、吸油性和水合能力小；热风干燥和喷雾干燥的大豆分离蛋白功能性质相似；真空冷冻干燥对大豆分离蛋白功能性质影响小。     

马来酸酐酰化改性对大豆分离蛋白功能性质的影响

研究马来酸酐酰化改性对大豆分离蛋白功能性质的影响。结果表明:随着马来酸酐用量的增大,大豆分离蛋白的酰化度增大,等电点降低;随着酰化度的增大,大豆分离蛋白构象松散,色氨酸残基的微环境趋向于暴露于水的状态,亲水性增强;经马来酸酐酰化改性后,大豆分离蛋白的溶解性、发泡性、乳化性及乳化稳定性均显著提升,但泡沫稳定性有所下降。研究表明,马来酸酐酰化改性大豆分离蛋白是一种非常有前景的功能性食品添加剂。     

大豆分级蛋白的功能性质评价

利用″碱溶酸沉″方法,得到富含大豆球蛋白的大豆分级蛋白产品Ⅰ和富含β-伴球蛋白的大豆分级蛋白产品Ⅱ。经与市售的大豆分离蛋白产品进行功能性质的比较,大豆分级蛋白的某些功能性质,如胶凝性、乳化性、发泡性得到了改善和提高。     

超微粉碎对大豆分离蛋白功能性质的影响

以大豆分离蛋白为原料,经不同程度超微粉碎后,得到不同粒径的超微粉体,并进行大豆分离蛋白功能性质的研究。试验结果表明,超微粉碎对大豆分离蛋白的功能性质有一定影响。随着粒径的不断减小,大豆分离蛋白的持油性、起泡性、泡沫稳定性、乳化性、乳化稳定性以及凝胶性在一定粒径范围内均有明显提高,而黏度降低。     

大豆分离蛋白美拉德反应研究进展

本文首先综述了美拉德反应对大豆分离蛋白的溶解性、乳化性以及凝胶性等一系列功能特性的影响,进而阐述了美拉德反应对大豆分离蛋白生物活性的影响,如抗氧化性和抗菌性。最后对大豆分离蛋白的美拉德反应在食品领域的研究进行了展望,以期对大豆分离蛋白的美拉德反应在食品领域的研究提供参考。     

大豆分离蛋白化学改性及其对功能性质影响

为改进大豆分离蛋白的功能性质,人们广泛研究大豆分离蛋白化学改性,经适当改性可产 生我们所期望功能性质,提高其作为功能性成分在食品工业中应用。本文主要综述近年 来国外有关大豆分离蛋白化学改性方面研究,并着重介绍大豆分离蛋白化学改性对其功 能性质的影响。     

大豆分离蛋白的改性及其对功能性质的影响

大豆分离蛋白是大豆蛋白最为精制的形式，作为一种组成成分，它广泛应用于食品工业，在不同的产品中表现出不同的功能。为了探讨改性大豆分离蛋白的功能性质，主要综述了近年来有关大豆分离蛋白物理、化学、酶法改性方面的研究，以及这些改性对大豆分离蛋白功能性质的影响，同时也提供了大豆分离蛋白基因工程改性方面的研究进展。结果表明，经过不同方式的适当改性可产生合适的功能性质，拓宽大豆分离蛋白在食品工业中应用的范围。     

紫苏分离蛋白功能性研究

为了开发紫苏蛋白在食品工业中的应用,以大豆分离蛋白为对照,研究紫苏分离蛋白的功能特性。结果表明：紫苏分离蛋白的溶解性与大豆分离蛋白的溶解性随pH值变化的趋势基本一致,但在等电点时紫苏分离蛋白的溶解性高于大豆分离蛋白。在pH7.0时,紫苏分离蛋白的持水性、起泡性及泡沫稳定性、乳化性和凝胶性均不及大豆分离蛋白。但紫苏分离蛋白的吸油性仅稍小于大豆分离蛋白,此外,在紫苏分离蛋白的蛋白质质量浓度为3g/100mL以后,其乳化稳定性与大豆分离蛋白的乳化稳定性基本相当。紫苏分离蛋白在食品加工中作为一种蛋白质强化剂具有一定潜力。     

物理方法对大豆分离蛋白功能性质影响

大豆分离蛋白因其高营养性和独特功能性质在食品工业中有着广泛应用。该文着重介绍一些物理方法,如超高压、超声波技术及加工方法对大豆分离蛋白功能性质改善效果,并对其作用机理进行简单介绍。     

Functional Properties of Lupin Protein Isolates (Lupinus albus cv Multolupa)

Lupin protein isolates were prepared by alkaline extraction and precipitation at pH 5.1, 4.2 and 4.9 and their functional properties investigated. Solubility, emulsification capacity, swelling and gelation properties were determined under different conditions of pH, ionic strength and heat treatment. Lupin protein isolates showed better solubility than soybean isolate and a similar emulsification capacity. Swelling and gelation were found to be inferior, but when modifications in the methods of isolate preparation were introduced these properties were significantly improved. Consequently, it is possible to consider lupin proteins as a potential substitute for soybean proteins in food applications.     

干燥方式对大豆分离蛋白功能性质的影响

本文以醇洗豆粕为原料制备大豆分离蛋白，着重探讨了冷冻和喷雾干燥两种干燥方式对大豆分离蛋白功能性质，如溶解度、凝胶性能、乳化性能、起泡性能与粘度等的影响。实验表明，冷冻干燥样品具有较低的粘度和溶解度，且凝胶性能和泡沫稳定性明显高于喷雾干燥样品；两种样品的乳化稳定性和起泡能力比较接近，但喷雾干燥样品的乳化活性略高于冷冻干燥样品。     

Investigations of Soybean 11S Protein and Myosin Interaction by Solubility, Turbidity and Titration Studies

Solubility tests, turbidity tests, and titration experiments were employed to study the possible protein-protein interactions between purified soybean 11S protein and skeletal muscle myosin and the involvement of protein subunits in the interactions. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) was used as an analytical tool for identification of the protein species. These tests indicate that these proteins interacted at temperatures between 85°C and 100°C. Solubility and titration experiments showed that acidic subunits of soybean US protein had little or no interaction with myosin heavy chain subunits. In contrast, soybean 11S basic subunits interacted with myosin heavy chains. The SDS-PAGE method indicated that eight commercial soy protein isolates had a similar protein species composition, but certain proteins in some isolates had lost their availability for water extraction. This may account for different functional properties exhibited by differen soy protein isolates.     

Functional Properties of Chinese Rapeseed Protein Isolates

A membrane-based protein isolation process developed in our laboratory produced two protein isolates from CH₃OH/NH₃/H₂O-hexane-extracted Chinese rapeseed meal. Both contained ～99% protein (NX6.25), and they were essentially free of glucosinolates or their breakdown products (<2,2 μmol/g). Their functional properties were evaluated and compared with a commercial soybean protein isolate. The precipitated isolate gave high values for all properties except nitrogen solubility index (NSI) while the soluble isolate showed excellent NSI and fat absorption but poor emulsification characteristics. They both had good foaming properties. The two Chinese rapeseed protein isolates complemented each other and were comparable to soybean protein isolate in most functions.     

超声处理对黑豆蛋白与可溶性多糖复合物功能性质及结构的影响

将可溶性多糖与黑豆蛋白进行复合可以改变蛋白的许多功能性质。采用荧光分析、圆二光谱检测超声处理对黑豆蛋白与可溶性多糖复合物蛋白的功能性质及结构的影响。结果表明,将黑豆蛋白与可溶性多糖以1∶2的比例混合时,复合物的乳化性最好,此时复合物乳液比较稳定。用不同超声时间处理上述复合物溶液,处理16 min的复合物的乳化性最好,处理8 min的复合物的乳化稳定性最佳。同时随着超声时间的延长,蛋白质二级结构中α-螺旋含量上升,β-折叠下降,说明蛋白质的结构与功能性质有着密切关系。适当的超声处理可以改变黑豆蛋白与可溶性多糖复合物的结构,提高某些功能特性。     

Study on the Functional Properties of Soybean Protein Isolate Cross-Linked with Gelatin by Microbial Transglutaminase

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.