啤酒糟单菌发酵与混菌发酵降解纤维素效果比较

Comparison of the degradation effects of cellulose between single strain and mixed strains fermentation with brewer's grains

研究以啤酒糟为主要原料,采用二次多菌种混合固态发酵生产蛋白饲料。为优选一次发酵菌种,选择黑曲霉及康氏木霉,以纤维素含量为指标,通过正交优化试验,优化单一菌种和混合菌种的最佳发酵条件,比较发酵结果。结果表明:黑曲霉在其最适宜条件下进行单菌发酵,测得的粗纤维质量分数为5.90%;康氏木霉在其最适宜条件下进行单菌发酵,测得的粗纤维质量分数为6.10%;而进行混菌发酵时,在料水比1∶2、混菌接种量20%(黑曲霉与康氏木霉的比例为6∶4)、30℃下培养3d的条件下,纤维素含量达到最低,质量分数为4.40%。表明混菌发酵比单菌种发酵降解纤维素效果更好。

The method of producing protein feed from brewer＇s grains by secondary solid-state fermentation with multiplex strains was studied. To optimize the primary fermentation bacteria, selecting Aspergillus niger and Trichoderrna koningii, the conditions of single strain fermentation and mixed strains fermentation by orthogonal design tests were optimized. The results indicated that under the optimum fermentation conditions of Aspergillus niger, the content of cellulose was 5.90% ;under the optimum fermentation conditions of Trichodetma koningii, the content of cellulose was 6. 10% ; the optimum conditions of mixed strains fermentation were as follows： the fermentation time was 3 d at 30℃, the ratio of feed to water was 1 ： 2, and inoculum amount was 20% （the ratio of Aspergillus niger to Trichodermakoningii was 6 ： 4）. Under the aboveeonditions, the content of cellulose was the minimum,only 4.4%. The results showed that the degradation effects of cellulose by mixed strains fermentation was better than that by single strain fermentation.