Effect of Different Pretreatment of Raw Material on the Quality of Bean Paste

In the study,in order to explore the effects of four different pretreatment methods on the quality of bean sauce,the conventional physical and chemical indicators of bean paste of four different pretreatment methods were analyzed,and the volatile compounds of bean paste by four different treatment methods were analyzed by headspace solid-phase microextraction(HS-SPME)coupled with GC/MS. The results indicated that the content of total acid,ammonia nitrogen,salt content and reduce sugar in bean paste were significantly different. Among them,the total acid content of scalding and bleaching soybean paste was 0.72 g/100 g,and the salt content was 13.2 g/100 g,which were higher than the other three pretreatment technologies. The highest amino nitrogen content was 0.82 g/100 g in atmospheric pressure cooking,which was 0.11 g/100 g higher than that in blanching bean paste. The highest reducing sugar content was 5.72 g/100 g in the bean paste treated with raw materials,and 3.38 g/100 g in the bean paste treated with blanching. A total of 62 volatile components were identified by HS-SPME-GC-MS. The volatile components of raw materials,blanching,atmospheric cooking,and autoclaving pretreatment samples were 22,23,19,and 27,respectively. The same components were 5 kinds(1-octene-3-ol,linalool,phenylacetaldehyde,2,5-dimethylpyrazine,2-ethylhexanol),characteristic flavor substances were 3,4,2 and 3 kinds,respectively. Compared with the other three pretreatment methods,blanching pretreatment had more flavor substances and characteristic flavor substances. Based on the analysis of the conventional physical and chemical indexes and volatile components,it was found that the blanching treatment was superior to the other three methods of raw material pretreatment.