玉米芯固态发酵生产蛋白饲料的工艺研究

Studies on technology for producing protein feeds from corncob by solid-state fermentation

以固态发酵培养方式,通过正交试验对黑曲霉和啤酒酵母在玉米芯和豆粕上共发酵生产饲料蛋白的条件进行了研究。在质量分数为80%的玉米芯和质量分数为20%的麸皮混合物中,加入含(NH4)2SO4质量分数2%,MgSO4.7H2O质量分数0.05%,KH2PO4质量分数0.01%的营养液(液料质量比1∶1),初始pH值为5.5,接种黑曲霉,接种量为10%,温度30℃,浅盘培养。黑曲霉培养48 h后接种酵母,接种量为10%;黑曲霉培养72 h后添加豆粕,物料中豆粕的质量分数为20%,再发酵48 h。结果表明:产品粗蛋白质含量达26.1%,净蛋白质增量为12.9个百分点。产品富含小肽和氨基酸,蛋白质水解度为9.4%。

Co--fermentation conditions for producing protein feeds from corncob;soybean meal with Aspergillus niger and beer yeast through orthogonal experiment were developed. A nutrient solution containing （NH4）2 SO4 of mass fraction 2%, MgSO4 · 7H2O of mass fraction 0.05% and KH2PO4 of mass fraction 0.01% （liquid： solid 1 ： 1） was added into the mixture of corncob with a mass fraction of 80% and bran with a mass fraction of 20%. Aspergillus niger was inoculated with an ineoculum volume of 10% under initial pH 5.5, temperature 30℃ and cultured in a tray. The yeast was added after culture of Aspergillus niger for 48 h, the incoeulum volume was 10% and soybean meal with a mass fraction of 20% was added after culture of Aspergillus niger for 72 h and then fermented for 48 h. The crude protein yield was up to 26.1%, the net protein content was 12.9 pereentge points. The results showed that the product contained rich small peptides and amino acids, and the degree of hydrolysis was 9.4%.