大豆蛋白组成与功能关系研究

研究了大豆蛋白的7S／11S比例对凝胶与乳化性能的影响,并测定了5种大豆蛋白的7S／11S及其乳化、凝胶性。发现随着7S／11S比例增大,凝胶硬和粘度降低,乳化能力增强。由此可见,大豆中的7S／11S是决定大豆蛋白功能性的关键因素之一,品种的差异造成了7S／11S的不同,进而影响了蛋白的功能。     

FORMATION OF HETEROCYCLIC AMINES IN MEAT EMULSION EXTENDED WITH SOY PROTEIN

Formation of heterocyclic amines (HAs) during heating of meat emulsions at selected temperatures was studied to determine the influence of soy protein and fat contents on yields of HAs. Meat emulsion with two different fat contents, 6% (low) and 19% (high), and with two soy protein contents, 0% (none) and 10%, were used in the study. The emulsions were heated at temperatures of 180 and 200C for times varying from 0 to 40 min. HAs namely IQx (2-amino-3-methylimidazo[4,5-f]quinoxaline), MelQx (2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline), and PhIP (2-amino-1-methy-6-phenylimidazo[4,5-b]pyridine) were identified and quantified in the meat emulsions. Concentrations of IQx were from 0 to 8.26 ng/g of emulsion; MeIQx concentrations were from 0 to 14.73 ng/g and PhIP concentrations were from 0 to 2.48 ng/g. Yields of the HAs depended on temperature, time, soy protein and fat contents. Formation of the HAs in the meat emulsions after an initial lag period followed first order kinetics. Increasing soy protein content decreased the maximum concentrations of IQx and MeIQx formed at the different heating condition.     

GROWTH OF Vibrio parahaemolyticus IN SEAFOODS EXTENDED WITH SOY PROTEIN CONCENTRATE, STRUCTURED PROTEIN FIBER, AND TEXTURED VEGETABLE PROTEIN

The survival and growth of Vibrio parahaemolyticus in soy-supplemented laboratory media and seafoods was studied. Structured protein fiber (SPF), soy protein concentrate (SPC), and textured vegetable protein (TSP) enhanced the growth of V. parahaemolyticus in liquid culture media. Growth of the bacterium was retarded in ground flounder, shrimp, and crab extended with SPF (10 and 25%) and SPC (5 and 10%) and stored at 15 and 25°C for periods of time ranging to 72 hr. Compared to controls, TSP promoted the rate of growth of V. parahaemolyticus when added to seafoods at levels of 5 and 10%. Inhibitory and stimulatory effects were attributed to possible differences in types of competitive microflora which may be indigenous to the three soy extenders and to variations in chemical composition and physical form. Caution is advised when formulating seafood-soy blends for distributing and marketing at 15°C or higher.     

ADSORPTION CHARACTERISTICS OF FUNCTIONAL SOY PROTEIN PRODUCTS

The moisture adsorption characteristics of three commercial functional soy protein products (two isolates and one concentrate) in the temperature range of 10 to 40C were studied. The temperature showed significant effect on both the change of moisture content during adsorption and equilibrium moisture content. The rate of moisture adsorption of a soy protein isolate at water activity of 0.84 increased, but its equilibrium moisture content decreased with the increase of temperature. The suitability of Peleg and GAB equations for modeling the change of moisture content during adsorption and adsorption isotherms was respectively examined, and the constants in both equations were determined. In the temperature range of 10C to 40C, the relative errors of predicted change in moisture content at water activity of 0.84 and predicted isotherms of a soy protein isolates were ranged from 1.36% to 4.85% and 2.80% to 3.63%, respectively. The two equations can be used to predict the change in moisture content during adsorption and isotherms of functional soy protein products at different temperatures with satisfactory accuracy.     

ACCEPTABILITY OF BEEF PATTIES EXTENDED WITH PORK AND/OR TEXTURED SOY PROTEIN1

Four beef or beef/pork ground meat blends were extended with textured soy protein (TSP) at 0, 10, 20 and 30% levels. Ground beef/pork/textured soy protein (TSP) patties with 30% TSP were rated lowest by consumers for raw color and appearance and overall cooked appearance. A beef (50%) and pork (30%) blend containing no TSP was rated highest by consumers for tenderness, flavor and overall desirability and higher by a trained sensory panel for flavor and overall desirability than blends containing TSP. Overall desirability ratings for visual and palatability characteristics of beef/pork meat patties were higher than for beef/pork/TSP blends. Results indicated a distinct advantage for palatability of the beef/pork blend as compared to beef/pork/TSP combinations.     

TEXTURE ANALYSIS OF TEXTURED SOY PROTEIN PRODUCTS: RELATIONS BETWEEN INSTRUMENTAL AND SENSORY EVALUATION*

The Minnesota Texture Method, designed to differentiate objectively textural differences in commercial textured soy protein (TSP) products and their mixtures with ground beef, was correlated statistically with sensory evaluation. The results indicated substantial predictability of sensory evaluations from MTM on eight selected commercial TSP products and their mixtures with ground beef.     

QUANTITATIVE DETERMINATION OF FAT, PROTEIN AND CARBOHYDRATES OF SOY PRODUCTS WITH INFRARED ATTENUATED TOTAL REFLECTANCE

Attenuated total reflectance (ATR), offering a possible rapid method for quantitative measurements of major nutritional components in food materials (fat, protein, carbohydrate), was employed to evaluate the composition of a variety of soy products. Using a sample cell developed in this laboratory, different sample particle sizes and forces applied to a mounted sample were investigated to determine if variations of this type would improve the accuracy and precision of the quantitative ATR technique. Correlations of 0.96 for fat and 0.94 for protein were achieved between a chemical analysis and the infrared technique using a baseline absorbance (A') calculation and 120 mesh samples at 40 lb force. Errors assignable to various aspects of the ATR technique are discussed.     

大豆蛋白质塑料研究进展

对大豆蛋白质塑料的研究内容与进展进行了概括,包括研究用大豆蛋白原料种类,大豆蛋白塑料的改性方法,如增塑、酸调、交联和填充等,以及大豆蛋白塑料制样方式等等,对其发展前景进行了展望。     

大豆不同脱腥方法对豆乳中蛋白质含量及脱腥效果影响的研究

大豆在加工过程中所产生的豆腥味是研究开发新的蛋白食品的主要障碍。在众多的脱腥专利技术中,结合热处理钝化大豆中的脂肪氧化酶是广为采用而较为有效的方法。由于热处理虽则使豆乳风味及口感有明显改善,但也程度不同地降低了大豆蛋白的可溶性,影响了大豆蛋白的得率。本文就几种行之有效的脱腥方法进行了比较,并对豆乳中蛋白质的影响规律作了某些探讨。     

高钙豆乳的钙吸收试验研究

通过动物试验检验发芽大豆制得的高钙豆乳的吸收效果.挑选40只平均体重18g～22g断乳小鼠分成5组,每组8只,喂饲低钙饲料的同时每天灌服不同含量的豆乳,饮用去离子水,在饲养15 d时做3 d钙代谢试验,测定指标有小鼠的最终体重、钙吸收率、骨钙含量、血清钙含量、股骨指数、股骨重量.喂饲发芽大豆制得的高钙豆乳的小鼠体重增长率为86.5%,钙吸收率为84.66%,股骨重量、股骨指数、股骨钙含量、血清钙含量与对照组比差异显著.     

大豆蛋白改性技术的研究

介绍了大豆蛋白的改性技术，包括物理、化学、酶和生物工程等技术。通过改性可以加强大豆蛋白的功能性质和营养，从而提高产品的应用范围。     

QUALITY CHARACTERISTICS OF TURKEY BOLOGNA FORMULATED WITH CARRAGEENAN, STARCH, MILK AND SOY PROTEIN

A low-fat (12%) high-added water (27%) bologna was formulated with mechanically deboned turkey meat (MDTM) and either carrageenan (0.5%), milk protein (2%), isolated soy protein (2%), or starch (2%). Cooking loss, purge loss during storage, cooked product bind, sensory characteristics, and batter viscosity were evaluated. Starch added late in the chopping process was the most effective in reducing cooking loss as well as decreasing (P < 0.05) purge loss during storage (both refrigerated and frozen storage). Cooked product hardness was increased (P < 0.05) by all test ingredients, except starch and kappa carrageenan added late in the chopping process. Kappa carrageenan incorporated before chopping significantly (P < 0.05) increased cooked product bind. Overall acceptability (sensory analysis) scores were higher (P < 0.05) when milk protein, isolated soy protein and starch were added during chopping, compared to their addition prior to chopping. However, this order of addition effect was not observed for either of the carrageenan treatments.     

大豆组织化蛋白产品质量因子分析

以二次旋转正交试验设计生产的25个组织化蛋白为分析样品,通过因子分析,探讨组织化大豆蛋白产品品质指标间相互关系。结果表明,可将7个品质指标用4个公共因子表示。因子1对密度和持水率等品质指标起支配作用,主要反映的是产品的质地;因子2对L＊和b＊起支配作用,主要反映产品亮度;因子3和因子4中分别只有a＊和硬度的载荷值较大,表明a＊和硬度与其他指标的直接联系较小。大豆组织化蛋白产品的评价指标及权重为持水率（25%）、硬度（25%）、L＊（25%）、a＊（25%）。密度或吸水率是评价组织化大豆蛋白的综合指标。