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.     

银耳的功能性及发展前景

综述了银耳的生物学特性,形态构造及营养成分,并对银耳的发展趋势进行了展望.     

酸浆籽分离蛋白的制备及其特性的研究

采用碱溶酸沉法提取蛋白,并对其功能特性进行了研究,结果表明:酸浆籽蛋白浸提的最佳工艺条件是:pH值9.O、提取温度40℃、提取时间20min、料水比1:14;酸浆籽分离蛋白的溶解性较好,具有一定的保水性、乳化性,但吸油性较差.     

菌类食品的功能特性及开发前景

本文介绍了菌类食品的生理活性物质及其功能特性，归纳了菌类食品的医疗和保健作用，展望了菌类食品未来的开发前景。     

EFFECT OF LACTIC ACID FERMENTATION OF CASSAVA ON FUNCTIONAL AND SENSORY CHARACTERISTICS OF FUFU FLOUR

The effects of lactic acid fermentation of cassava on the functional and sensory characteristic of fufu flour were investigated. Two strains of Lactobacillus plantarum were used as starter cultures for the fermentation of cassava to fufu for 96   h. The resultant wet fufu samples were dried at 65C in a cabinet dryer for 48   h, and were analyzed for functional and sensory characteristics.
Fermentation reduced the water-binding capacity of the fufu flour from 176.6% to between 118 and 125%. The pasting characteristics of the traditional and starter culture-fermented fufu flour samples were not significantly different from that of the unfermented cassava flour. When subjected to sensory evaluation, the traditional and starter culture-fermented cassava fufu flour were not significantly different in terms of color, odor and texture, but the cassava fufu flour produced, using starter culture SL19, had the highest overall acceptability ( P <  0.05).

PRACTICAL APPLICATIONS

Traditionally, processing of cassava to fufu is usually carried out by using the old stock from a previous fermentation to initiate the fermentation of a new batch. This old method usually results in fufu that has a strong odor that may not be acceptable to some consumers. The use of starter culture like Lactobacillus plantarum will reduce the strong odor of fufu ; this will increase its acceptability by consumers and ensure the overall quality. Also, the functional properties of fufu are not affected. The development of lactobacilli strains could help in optimizing the traditional processes, therefore increasing the economic returns.     

常见食用豆类的营养特点及功能特性

食用豆类是人类三大食用作物之一,具有非常高的营养价值和生理功能特性.介绍常见食用豆类的发展概况、营养特点、功能特性及其应用.     

榨菜腌制品风味研究进展

阐述了榨菜腌制品的风味成分、形成机理，分析了主要风味物质的呈味特点，并介绍了榨菜腌制品风味物质提取、分离、检测的研究新进展。     

磷脂酶A改性的蛋黄功能性质及其对蛋制品品质影响

采用磷脂酶A水解蛋黄中的卵磷脂生成溶血卵磷脂，转化度为80％。研究了磷脂酶A改性蛋黄的功能性质及其对蛋黄酱和面包品质的影响。改性蛋黄功能性实验表明：酶法改性之后的蛋黄比普通蛋黄具有更大的乳化稳定性、吸湿性，以及显著的耐热性。蛋黄酱应用实验表明：相对普通蛋黄制作的蛋黄酱，酶法改性的蛋黄制作的蛋黄酱黏度是其1．5倍，而且改性蛋黄制作的蛋黄酱可经受100℃，30min的热处理而不会有油析出。面包应用实验表明：改性蛋黄制作的面包具有更高的综合评分，比普通蛋黄对面包具有更好的抗老化效果。     

纸型酸芥菜的加工工艺

以酸芥菜为原料研究纸型蔬菜的加工工艺、操作要点以及各项理化指标的检测.结果表明,原料经过脱盐,采用高速打浆机粉碎并添加0.4%羧甲基纤维素钠、0.5%海藻酸钠、1.0%可溶性淀粉、0.25%大豆分离蛋白,选择布料作为涂布浆料的介质,在75℃条件下烘烤1.5 h;在其表面刷调味料,其组成为味精1%、白糖2%、麦芽糊精5%、水90%、植物油2%.制品的水分含量为2.3%,水分活度0.41,含盐量3.4%、酸度0.7%、亚硝酸盐1.51 mg/kg.     

重庆奉节大头菜的加工工艺

本文介绍了以重庆奉节的生大头菜为原料,利用腌制池和腌制坛,经过两次加盐换池,使大头菜成熟,并加工,从而得到色,香,味俱佳的香辣大头菜腌制品的两种生产工艺.分别为风脱水工艺和盐脱水工艺.     

RHEOLOGICAL CHARACTERIZATION of COFFEE MUCILAGE

Rheological behavior of mucilage obtained from two varieties of coffee grown in Colombia (Caturra and Colombia) was studied as a function of ripe cherry content (RCC) and postharvest time (PHT). A Brookfleld HB DV-III viscometer was used in concentric cylinder geometry over a shear rate range of 4.8 to 120 s⁻¹. the power-law model was used to describe the shear stress versus shear rate data, and the consistency index (K) and flow behavior index (n) were determined. the mucilage is a highly viscous and pseudoplastic (n < 0.3) fluid. the K increased and n decreased as the RCC and PHT increased. the mucilage of the Caturra variety was more viscous and shear thinning than that of the Colombia variety. Microstructural examination of the mucilage revealed that certain weak structures as phloem vessels found in the mucilage may be destroyed upon application of shear stress and may contribute to the pseudoplastic nature of the mucilage. Diffusion of tannin from the pulp to mucilage with delay in postharvest processing may be responsible for increased apparent viscosity with increased PHT.     

EFFECT OF DEHYDRATION ON PHYSICOCHEMICAL PROPERTIES OF MUSTARD, MINT AND SPINACH

Mustard, mint and spinach were dehydrated in a sun and cabinet drier and were subsequently studied for rehydration characteristics. Dehydration ratio ranged from 12.37:1.0 to 23.37:1.0, while rehydration ratio varied from 1.0:2.84 to 1.0:3.76 for three green leafy vegetables. The bulk density of dried vegetables varied from 55.1 to 171.5 kg/m³, whereas the angle of repose was in the range of 33.2–52.4°. Color values L, a, b and ΔE were reduced with blanching and drying. Retention of chlorophyll, β‐carotene and ascorbic acid in dehydrated products varied from 41.87 to 61.35%, 22.26 to 55.16% and 13.36 to 37.53%, respectively. On rehydration, the ascorbic acid retention was further reduced to 4.17–11.55%.