干酪素高速贴标胶粘剂的研制

介绍用干酪素、聚丙烯酰胺、尿素、淀粉为原料制成了能适用于36，000瓶／小时以上的啤酒生产线的高速贴标胶粘剂。研究了各种因素对胶粘剂性能的影响。结果表明，胶粘剂的粘度、干燥速度、冷藏稳定性随干酪素用量的增加而增大；贮藏稳定性随pH值增加而上升；聚丙烯酰胺用量增加时，粘度也有较大的增加。     

Fractionation of Caseins by Anion-exchange Chromatography Using Food-grade Buffers

: Caseins prepared by microfiltration of bovine skim milk were fractionated using anion‐exchange chromatography. Laser densitometry of electrophoresis gels was shown to be sufficiently quantitative to perform accurate mass balance calculations detailing the fate of each casein fraction. L‐cysteine was successfully used as a reducing agent instead of traditional toxic agents, such as dithiothreitol or β‐mercaptoethanol, enabling development of the first food‐grade buffer system for casein fractionation. More salt was required for elution of the casein fractions having a greater charge: α_s‐casein > β‐casein > κ‐casein. Increasing flow rate decreased the extent of separation. Use of smaller beads was suggested as a method to maintain separation at increased flow rate.     

牛乳酪蛋白源活性肽制备及结构研究现状

从牛乳酪蛋白源活性肽、制备方法、结构分析鉴定等方面，对以牛乳酪蛋白为原料研制开发的活性肽类进行了综述，并总结了目前人们从酪蛋白中发现的活性肽的氨基酸组成结构。     

Interaction of Commercial Dairy Proteins and Chicken Breast Myosin in an Emulsion System

The compatibility of commercial dairy proteins with chicken breast myosin in an emulsion system was examined. SDS-PAGE of the solution remaining after emulsion formation indicated that myosin incorporation into the cream layer was much more limited with the flexible additives such as sodium-caseinate and milk protein isolate resulting in decreased emulsion stability. However, myosin incorporation and emulsion stability were maintained with whey protein concentrate or whey protein isolate at all additive levels. No hydrophobicity changes were found in myosin with additive mixtures except for heated myosin and WPC (P=0.04). The stability of an emulsion was primarily determined by the amount of myosin incorporated.     

酪蛋白源ACE抑制肽干燥工艺的探讨

喷雾干燥技术和冷冻干燥技术对酪蛋白源ACE抑制肽的抑制活性影响差异不显著(P>0.05),通过比较不同的喷雾干燥工艺条件,确定其进口温度范围为140～160℃,出口温度范围为70～90℃。1L小试和10L小试放大试验结果证实,肽得率稳定,为29%左右,半抑制质量浓度(IC50)为0.53g/L。     

Mass Production Method for Rice Protein Isolate and Nutritional Evaluation

We developed a method for mass production of rice protein isolate (RPI) and evaluated its nutritional quality in rats. To obtain thick slurry, rice flour was mixed with a 0.6% Termamyl 120L-solution (1:2, w/v) at room temperature (～23°C). The slurry was heated at 97°C for 2 hr with stirring. Gelatinization and liquefaction occurred simultaneously. RPI obtained by filtration and washing with boiling water, was more than 90% pure protein (dry matter basis). It also contained 6.4% dietary fiber, 1.3% ash, and 1.1% carbohydrate. RPI diets (40–50%) allowed the maximum growth in rats comparable to that with 25% casein diet.     

Preparation of Casein Films by a Modified Wet Spinning Process

Casein films prepared by a modified wet-spinning process were studied using microscopy and measurements of physico-chemical and mechanical characteristics. The pH of the film-forming solution was critical for film properties. The most effective films were formed with pH 9 film-forming solutions. They had low solubility in water and highest tensile strength (4.5 MPa), highest percentage elongation at break (68.6%) and lowest water vapor permeability (3.9 10^-10 g.m^-1.s^-1.Pa^-1) values. Scanning electron micrographs revealed that those films had a denser ultrastructure than the others.