Comparison Of ?-amylase Inhibitors In Different Kinds Of White Kidney Beans And Research And Development Of Its Jelly Products

The ?-amylase inhibitor??-AI?from the white kidney beans?phaseolus vulgaris?has the ability to inhibit the decomposition of starch.This kind of protein product has attracted much attention from consumers.However,the form of this kind of product is relatively unitary.Developing a jelly product which is suitable for all ages and convenient to carry conform to the needs of consumers.However,the?-AI is unstable.So and it is very important to maintain its efficacy during the development of the jelly product.On the basis of previous studies,the following progress has been made in this paper:1 The nutrient components and?-AI characteristics of different varieties of white kidney beans are compared to screen the source of white kidney beans that containing the best?-AI characteristics.Seven varieties of white kidney beans are collected and the nutrient contents of them are compared by the national standard method.The nutritional content of variety P1was significantly higher than that of other groups.The?-AI crude protein of different varieties was extracted by water extraction and alcohol precipitation method.And the characteristics of?-AI were compared.The?-AI in white kidney beans shows better thermal stability?60°C?and pH stability than common proteins.The extraction rate,inhibitory activity,temperature and pH stability of variety P1 is significantly higher than those of other varieties,which was the best source for the preparation of?-AI.2 In this experiment,the formula is optimized and jelly products with the function of inhibiting the decomposition of starch are prepared.The effects of apple juice,compound gum,sodium cyclamate and potassium sorbate on?-AI inhibition rate are clarified.Apple juice shows the greatest effect on?-AI inhibition rate,compound gum is the second,potassium sorbate is the third and sodium cyclamate is the last.Furthermore,with?-AI activity and sensory score as research indicators,the optimal formula of jelly products is developed by single factor and orthogonal test.And the optimal formula is 15%apple juice,1%compound gum,0.3g/kg potassium sorbate and 0.3g/kg sodium cyclamate.The inhibition rate of?-AI in solid jelly was 45.8%,higher than that of typical commercial starch blocking products phase 2?42.6%?.On the basis of this formula,the optimal formulation of?-AI absorbable jelly is selected by changing the dosage of complex gel?carrageenan:konjac gum:xanthan gum=27:18:4?.The optimal formulation is 15%apple juice,1%complex gel,0.3g/kg potassium sorbate and 0.3g/kg sodium cyclamate.And the inhibition rate of?-AI in solid jelly was 46.2%,which is higher than that of phase 2?42.6%?.3 This experiment is committed to investigate the effects of the sterilization methods on?-AI characteristics and quality of jelly products?solid jelly and absorbable jelly?and to to develop a sterilization process capable of maintaining the functional activity for inhibiting starch decomposition and organoleptic quality characteristics of the product.Heat sterilization?65°C,25min;60°C,30min?and irradiation sterilization(⁶⁰Co-?ray irradiation 2kGry,4kGry,6kGry)is used to sterilize jelly products.The primary,secondary and tertiary structures of?-AI crude protein is studied by SDS-PAGE,circular dichroism and fluorescence spectra.Texture analyzer and rheometer is used to reveal the effect of flavor and quality of jelly products.In addition to heat sterilization 60°C,30min,the rest of the sterilization can control the microorganisms within the permitted range,and it shows certain influence on the structure,activity and quality of the jelly products.Among them,65°C,25min heat treatment and 4kGry ray irradiation can not only maintain the?-AI functionality in the jelly,but also maintain the better microbial safety,flavor characteristics and hardness,chewiness,recovery,cohesiveness,elasticity and other quality of the jelly,which is the best sterilization process.