The Lactic Acid Bacteria And Bacillus Licheniformis Are Used To Ferment Soy Sauce Residue

One bacillus strain and eleven Lactic acid bacteria (LAB) strains were isolated from soysauce residue materials, through the physiological and biochemical experiments andthe identification of16S rDNA，the strains were identified as one Bacillus licheniformisnamed Tao1; Three Lactobacillus casei respectively named T1, T2,T3; Four Enterococcusfaecium respectively named T4,T5,T11,T13; Three Lactobacillus plantarum respectivelynamed T9,T10,T12; One Pediococcus pentosaceus named T7.These strains had well probioticcharacteristics of producing acidity, Artificial gastric acid-resistant, Salt tolerance, Artificialbile acid-resistant and Heat-resistant. Bacillus licheniformis Tao1, Enterococcus faecium T5,T11and Lactobacillus casei T2had better probitic characteristics than other strains. Growthof high viabilities of Tao1, T2, T5, T11were observed，the growth of Tao1, T5, T11were fastand the pH of T2was low in the process of culture. The strains of Tao1, T2, T5and T11hadwell antimicrobial activity to Listeria monocytogenes, Salmonella enteric and Staphylococcusaureus. These results show that these microorganisms could be used as starter culture with theability to ferment soy sauce residue.Tao1was used for fermenting soy sauce residue, the results showed that liquid statefermentation was better than solid state fermentation. When the soy sauce residue and cornstarch residue ratio of1:1, the greater number of viable cells was obtained.Using orthogonal optimization for added auxiliary elements, the results showed that under thecondition of magnesium sulfate1g/L, manganese sulfate2g/L, calcium carbonate2g/L, thenumber of viable cells in the culture medium up to the maximum number of6.55×10~9cfu/mL.T2, T5and T11were used for fermenting soy sauce residue, the results also showed thatliquid state fermentation was better than solid state fermentation. The fermentation also canoccur in aerobic environment. Using Plackett-Burman experimental design to study factors ofviable cells in fermentation, the content of glucose and soya peptone in medium, and the ratioof inoculating strains were selected three significant factors, and then choose these threefactors as the main subjects for single factor experiment optimization. The results shows thatwhen the concentration of glucose and soya peptone respectively were20g/L and3g/L, theratio of inoculating strain Lactobacillus casei and Enterococcus faecium was2:1, the viable cells can reach to maximum. Using the center of response surface experiment for furtheroptimization, the model calculate that when the concentration of glucose and soya peptonerespectively were30.46g/L and2.80g/L, the ratio of inoculating strain Lactobacillus caseiand Enterococcus faecium was2.41:1, the viable cells can reach to5.156×10~9cfu/mL. In theverification experiments under optimal conditions, the viable cells reach to5.038×10~9cfu/mL.The crude protein, lipids, fiber and ash were detected. Compressed with pre-ferment, themedium which had fermented contain more crude protein and ash, and had less lipids and thatwas suit with feeds’ require. All results show that soy sauce residue could be used as mainmaterial for fermentation by Lactobacillus casei and Enterococcus faecium, and the finalproduce could be used as feeds.