Study On Processing Of Easy-to-cook Beans

As a common edible legume in China,the protein,fat,dietary fiber and essential amino acid content of non-soybean legumes are significantly higher than that of staple food.However,it takes a long time to cook,which brings a lot of inconvenience to people's daily cooking.In this paper,the processing of easy-to-cook beans,including red adzuki beans and kidney beans were studied.The results were as follows:The thermal processing process consisted of soaking,heat treating,enzymatic hydrolysis and drying.The results of single factor experiment showed that compared with water immersion,acid treatment had no significant change in the seed coat structure of soybeans,and the sensory score decreased due to acid residue;compared with roasting,steaming was more conducive to the improvement of seed coat permeability,the hardness and chewiness of soybeans were better,and the appearance of soybeans was good;cellulase treatment was better than protease treatment and enzymatic treatment after heating was better than that before heating;hot air drying could avoid the cracking rate and hardness increase caused by microwave drying.Response surface test was used to optimize the technological conditions.The heat-processing conditions of easy-to-cook red adzuki beans were as follows: soaking in warm water at 50 ° C for 4 hours,steaming at 100° C for 15 minutes,soaking in cellulase solution at 85U/m L for 47 minutes with the ratio of material to liquid of red adzuki beans to soaking solution was 1:6,then drying in hot air at 110 °C for 70 minutes.The heat-processing conditions of easy-to-cook kidney beans were as follows: soaking in 50° C water for 40 minutes,steaming at 100° C for 31 minutes,soaking in 128 U/m L cellulase solution for 30 minutes with the ratio of kidney beans to soaking solution was 1:6,and then drying by hot air at 90° C for 105 minutes.Vacuum freeze-drying technology was used in non-thermal processing.The process included soaking,pre-freezing,sublimation drying and analytical drying.The eutectic point temperature of red adzuki bean and kidney bean was-9.10° C and-9.82 ° C respectively.Through single factor experiment and orthogonal experiment,the non-thermal processing conditions of easy-to-cook red adzuki bean were determined as follows: soaking at 50 ° C for4 hours,-25 ° C pre-freezing for 4 hours,-45 ° C sublimation drying for 30 hours and analytic drying for 10 hours at 50 °C.The non-thermal processing conditions of easy-to-cook kidney beans were as follows: soaking at 50 ° C for 4 hours,pre-freezing at-35° C for 4hours,sublimation drying at-45 ° C for 30 hours and analytical drying at 50 ° C for 10 hours.The cooking time of easy-to-cook beans obtained by thermal and non-thermal processing was significantly shortened,which was the same as that of rice.Among the four kinds of non-thermal and thermal processed red adzuki beans and kidney beans,the sensory evaluation of non-thermal processed kidney beans was poor.After rehydration,the other three products showed good taste and inherent aroma.They were lighter than raw beans but had natural color.The granules were full and the breakdown rate was similar to that of raw beans.After heat treatment,the contents of protein,fat and other nutrients in beans decreased,except carbohydrates increased significantly.After non-thermal processing,the moisture content of beans was less than 2%,and there was no significant change in protein,fat,carbohydrate and ash.