Study On Preparation Of Soybean Paste Flavor Base By Enzymolysis Technology And Traditional Fermention

Soybean paste as Chinese traditional fermented soybean food, loved by many people. Traditional soybean fermentation cycle is long, its safety can not be guaranteed, this research subject combined artificially inoculated fermentation with enzyme technology to shorten the production cycle, and soy sauce flavor base material produced by spray drying method, improves the use limitation of soybean paste, enlarge the using range of the bean paste, can greatly reduce the transportation cost, and make it easier to use, soy sauce flavor base material can be also widely used in the flavoring of soup and instant noodles, puffed powder food and so on.It provids unique soybean paste flavor to the food and has a huge market prospects.In this experiment, soybean meal, wheat flour and wheat bran as raw material, Aspergillus niger and Aspergillus oryzae strain koji dual conditions were explored through by measuring the number of spores and amino nitrogen content, to determine the best conditions of koji, the optimum starter-making conditions were determined as follows: inoculation quantity2.5%, proportions of bacterium 3:1, koji making time 65 h, starter making temperature of 29.5℃, obtained a number of spore was 3.75×108cfu/g under this condition, the content of amino nitrogen was 0.721%.On the basis of traditional fermentation, adding protease and amylase in the koji to make protein and starchl in the raw materithe fully hydrolyzed, improve the utilization rate of raw material and shorten the fermentation time. On the basis of single factor test of the added amount of protease and amylase, enzyme dosage, reaction time, reaction temperature and ratio of water to material, the amino nitrogen content and reducing sugar content as indicators, five factors and four levels of orthogonal experients were made, the optimum parameters were as follows:dosage of protease 1%, amylase dosage 3%, hydrolysis time 7 h, reaction temperature 60℃, ratio of water to material 1.5:1.T yeast and Lactobacillus were cultured in 0,4%,8%,12% four different salt concentrations of Yeast culture and MRS medium, every 5 hour measure its growth status and draw the growth curve, The results show that yeast and Lactobacillus good salt tolerance. By measuring the changes of pH, total acids, total ester and sensory evaluation during the fermentation of soybean paste to study mixed bacteria (Lactobacillus biomass:T Yeast biomass is 10:1) inoculation, the amount of salt added, the fermentation temperature, fermentation time on the fermentation process and the effect of fermentation. The optimum fermentation conditions were:inoculum size 1.2 X 107 cfu/g, the amount of salt added 7.5%, fermentation temperature 35℃, fermentation time 13d.The optimum temperature and time of the bean jam by color, aroma, taste, body sensory evaluation, the Maillard reaction is determined respectively 80℃,4 h, and then soybean paste volatiles were collected by SPME, and identificated by GC-MS.24 compounds was detected in the samples of nine kinds of alcohols, eight kinds of esters, one kind of acid, three kinds of n-type, one kind of aldehydes, two kinds of phenols. Wherein higher levels of eight kinds of substances as 2.500% 1-pentanol,3-methyl-3-heptanol 2.315%,12.920% benzene acetaldehyde, ethyl benzoate 6.437%,3.420% ethyl acetate in benzene,4-ethyl guaiacol 5.793%,16.990% ethyl cetane, linoleic acid ethyl 39.440%.After the process of dilution, homogenization, sauce flavor base powder were obtained under the spray drying conditions of inlet air 80℃, outlet air 180℃.