Studies On The Optimum Of Solid-state Fermentation Condition Using A Mixture Of Bean Curd Residue And Marc And Utilization Of The Fermented Materials

This paper adopts the method of solid-state fermentation,to degrade the crude fiber of the mixture of bean curd residue and marc and other ingredients to achieve the improvement of its palatability,while several favorable secondary metabolites generated in the process of fermentation for the purpose.By means of solid-state fermentation gives the fermented the mixture of bean curd residue and marc unique flavor,which could add a raw material widely used as food.In this paper,Bacillus natto and Saccharomyces cerevisiae were used independe-ntly,as the start stain of solid-state fermentation the mixture of bean curd residue and marc,to study the degradation of the mixture of bean curd residue and marc crude fiber case and other favorable secondary metabolites during fermentation process were determined. The main research results are as follows:1. Using acid alkali digestion method to determinate crude fiber content of the mixture of bean curd residue and marc.measured the reducing sugar content of the mixture of bean curd residue and marc to verify the degradation of crude fiber.and this experimental determination of reducing sugar used 3,5-dinitrosalicylic acid assay.In optimal conditions, the experimental results show that solid-state fermentation of Bacillus natto the mixture of bean curd residue and marc degradation rate of crude fiber is 47.87%,while solid-state fermentation of Saccharomyces cerevisiae the mixture of bean curd residue and marc degradation rate of crude fiber is 40.45%.The changes of reducing sugar content in the mixture of bean curd residue and marc accurately verify the degradation of crude fiber during fermentation process, and which proved crude fiber content of the decline was due to degradation of the results of original strain.2. The best fermentation condition optimized by single factor and the orthogonal test method was 55% initial water content of the culture medium, seeding volume 10%, initial pH5, the fermentation temperature 37℃, fermentation time 48h,the bean curd residue and marc load ratio 2:1, and filled the mixture of bean curd residue and marc amount 30 g/250 mL flask. While Solid-state fermentation the mixture of bean curd residue and marc degradation of crude fiber with Saccharomyces cerevisiae optimal fermentation conditions was:65% initial water content of the culture medium, seeding volume 8%, initial pH8, the fermentation temperature 22℃, fermentation time 48h,the bean curd residue and marc load ratio 2:1, and filled the mixture of bean curd residue and marc amount 30 g/250 mL flask.3.Adopted alloxan to determine glutathione in the mixture of bean curd residue and marc fermented with Saccharomyces cerevisiae.Under the optimal conditions, the glutathione content detected before and after fermentation in the mixture of bean curd residue and marc is 166.94 mg/g and 256.63 mg/g respectively, increased yield by 53.73%.4.Determination of the yield of nattokinase and y-aminobutyric acid content before and after fermented the mixture of bean curd residue and marc with Bacillus natto. Under the optimized experimental conditions, measured by fibrin plate method the mixture of bean curd residue and marc nattokinase yield,experiments results showed that the fermented mixture of bean curd residue and marc nattokinase production rate of 1025 IU/g, while the pre-fermented bean curd residue and marc was not detected of nattokinase.Determination by HPLC the mixture of bean curd residue and marc y-aminobutyric acid content, the result is pre-fermented bean curd residue and marc was not detected in y-aminobutyric acid, while fermented bean curd residue and marc of y-amino acid content of 0.037 mg/g.5.The mixture of bean curd residue and marc fermented by Saccharomyces cerevisiae made into powder and mashed microparticles respectively which could be widely used in food processing. Textural analysis testified thay some textural properteis, such as hardness, chewing and adhesion, of mashed microparticles fermented and beef burger made from it were superior to those of the corresponding unfermented materials.