Comparison of organic acid production capacity of licorice residues fermented by single and complex bacteria
The aim of this experiment was to evaluate the effects of single and compound probiotics on the quality of licorice residue fermented feed.The experiment used licorice residue as the basic raw material,compounded with bran,soybean meal and molasses,on the basis of which single bacteria(Lactobacillus plantarum,Saccharomyces cerevisiae)and compound bacteria(Lactobacillus plantarum,Saccharomyces cerevisiae,Bacillus subtilis)were used as the fermentation agents,and the total acid content of fermented feed was determined with the help of the alkali titration method in the food testing,and the quality of fermented feed was measured by comparing the total acid content of the fermented feed with pH combined with the organoleptic evaluation.The results showed that:(1)Single bacteria fermented under different carbon and nitrogen ratios,and the content of organic acid generated at a carbon and nitrogen ratio of 30 increased 2.8 times compared with that at a carbon and nitrogen ratio of 25.(2)The content of organic acid reached the highest value at the 7th day of fermentation of the single bacteria,and the pH reached the lowest value at the 7th day of fermentation.3)Organic acid production in licorice pomace fermented feed was increased by 52%and 52.48%in the complex probiotic fermentation groups(groups E and F)compared with monobacterial brewer's yeast group(group B).It could be seen that the composite probiotics(Lactobacillus plantarum,Saccharomyces cerevisiae,Bacillus subtilis)were conducive to the promotion of licorice residue feed fermentation,both the odor and the amount of organic acid production was better than a single strain of licorice residue fermentation,licorice residue had the potential value of becoming a fermented feed.
licorice residuecomplex bacteriaorganic acidsolid state fermentation