复合益生菌固态发酵酒糟条件的研究

Research on solid-state fermentation conditions of distiller's grains by compound probiotics

该试验以白酒酿造的副产物酒糟、菌糠、麸皮和洗米糠为原料,添加以芽孢杆菌(Bacillus)K、酿酒酵母(Saccharomyces cerevisiae)S、屎肠球菌(Enterococcus faecium)Q三种益生菌1∶1∶1(V/V)混合制备的高生物活性发酵剂进行固态发酵,以发酵前后pH和蛋白品质为指标确定最佳配方,通过单因素及正交试验优化发酵条件。结果表明,当酒糟∶菌糠∶麸皮∶洗米糠质量比为1∶5∶2∶2时,pH降低了0.22,粗蛋白(CP)、酸溶蛋白(ASP)含量和ASP/CP分别提高了9.94%、66.03%和51.29%;确定最佳发酵条件为发酵时间3 d,发酵温度43℃,水分含量50%,接种量10.5%。在此优化条件下,CP、ASP含量、ASP/CP和蛋白溶解度分别提高了11.06%、95.77%、76.23%和14.84%。研究表明,利用复合益生菌固态发酵酒糟可以改善酒糟的蛋白品质,为酒糟的二次利用奠定了基础。

Using the distiller's grains(a by-product during Baijiu brewing),mushroom bran,bran and washed rice bran as raw materials,the solid-state fermentation was carried out by adding a high biological activity starter culture prepared with 1∶1∶1(V/V)of Bacillus K,Saccharomyces cerevisiae S and Enterococcus faecium Q.The optimal formula was determined by pH and protein quality before and after fermentation,and the fermentation conditions were optimized by single factor and orthogonal tests.The results showed that when distiller's grains,mushroom bran,bran and washed rice bran mass ratio was 1∶5∶2∶2,the pH decreased by 0.22,the contents of crude protein(CP),acid soluble protein(ASP)and ASP/CP increased by 9.94%,66.03%and 51.29%,respectively.The optimum fermentation conditions were determined as follows:fermentation time 3 d,temperature 43℃,moisture 50%,inoculum 10.5%.Under these optimal conditions,the contents of CP,ASP,ASP/CP and protein solubility increased by 11.06%,95.77%,76.23%and 14.84%,respectively.The study showed that solid-state fermentation of distillers'grains with compound probiotics could improve the protein quality of distillers'grains and laid a foundation for the secondary utilization of distillers'grains.