Study On The Fermentation Of Soybean Dregs By Neurosporasitophila

In this thesis,in order to reduce the content of cellulose,improve the content of carotenoids,and then improve the nutritive value and edible of soybean dregs,soybean dregs as the main raw material has been fermented through Neurospora sitophila.The results provide the theoretical basis for soybean dregs as the function food.The optimum technological conditions for the soybean dregs cake has been developed.First of all,to improve the taste,soybean dregs has been fermented by Neurospora sitophila.The proportion of acid detergent fiber and neutral detergent fiber in the soybean dregs has been reduced.The optimum fermentation conditions were optimized by single factor test and orthogonal test design.With acidic detergent fiber and neutral detergent fiber as indicator,single factor test was carried out to control the fermentation temperature,fermentation time,solid-liquid ratio,base load and inoculation amount.And then the fermentation time,the solid-liquid ratio,the base load and the inoculation amount were further tested by orthogonal test.The results showed when the fermentation time was 9 days,the base load was 8 g/250 mL,the inoculation quantity was 5 mL(1×106CFU/mL),the ratio of solid to liquid was 0.25,the content of acid detergent fiber in soybean dregs decreased obviously.The content of acid detergent fiber in soybean dregs decreased from 34.15%to 18.02%(scheme 1).Also,when the fermentation time was 8 days,the base loading quantity was 10g,the inoculation quantity was 3ml,the solid liquid ratio was 1:3.The content of neutral detergent fiber in soybean dregs decreased from 61.47%to 32.12%.(scheme 2).The water holding power(WHC)of soybean dregs was 419.25%and 409.36%after fermentation by scheme 1 and scheme 2,respectively,so the scheme 1 was chosen for following research.Under the optimum fermentation conditions of cellulose degradation,the carotenoids content was improved by Neurospora sitophila fermentation to improve the nutritive composition.Using carotenoids content as indicator,single factor experiment was carried out by changing the type and concentration of inducer(glucose,maltose,lactose,sucrose,xylose).The carotenoids was extracted by acid-hot wall-breaking and acetone extraction method.The content of carotenoids was measured by the ultraviolet spectrophotometer under 475nm.The results showed that the content of carotenoids was276.46 ?g/g,327.35 ?g/g,190.37?g/g,254.27 ?g/g and 189.25?g/g when the concentration of glucose,maltose,lactose,sucrose and xylose was 2.5 g/L,1.5 g/L,1.5 g/L,2.5 g/L and 2.5 g/L respectively.So maltose was used as the optimum inducer.Further,when the culture time was 72 h,the activity of phytase and xylanase reached the maximum of 53U/mL and 1599U/mL respectively.The cellulase activity reached the maximum of 94.37 U/mL at 60 h.Finally,the hardness,elasticity,masticatory,cohesion and resilience of three kinds of soybean dregs in the fermentation process were analyzed with Texture analyzer.Through sensory evaluation experiment,the best technology of bean dregs cake processing is obtained.The optimum technological conditions for the soybean dregs cake were developed as following:the amount of soybean dregs was 55%,the amount of cassava powder was 14%,the amount of coconut powder was 25%,the amount of sugar was 3%,and the amount of salt added was 3%.