复合发酵棉籽粕菌种筛选、鉴定及其发酵工艺参数优化研究

通过对发酵棉籽粕效果优良菌株的筛选、鉴定及其复合发酵最适工艺条件的研究,探讨发酵对棉籽粕脱毒效果及粗蛋白(crude protein,CP)含量等的影响.筛选并利用三株发酵效果优良的菌株(两株酵母和一株霉菌)对棉籽粕底物进行发酵,结果表明:与发酵前相比,底物中游离棉酚(free gossypol,FG)含量显著降低(P<0.05),并显著提高了CP含量(P<0.05).经工艺优化试验研究,得到较为理想的发酵工艺条件:底物组成为棉籽粕70%、玉米20%、糖蜜10%,添加3%硫酸铵,底物与水比例为1:0.6,三菌种(S1:S3:S6)接种比例为3:3:2,接种量为5%,自然pH.

Mixed Culture Solid Fermentation for Detoxification of Cottonseed Meal

Strain screening and fermentation parameter optimization for mixed culture solid fermentation of cot-tonseed meal were conducted with purpose of cottonseed meal detoxification. The effects of the fermentation on the degradation rate of free gossypol (FG) and crude protein (CP) content of cottonseed meal were determined. Results: The fermentation with three screened strains can degrade FG in the fermented substrate significantly (P<0.05), and improve CP content significantly (P<0.05). The following proper fermentation parameters are established: substrate is composed of 70% cottonseed meal, 20% corn flour and 10% molasses; ammonium sulfate dose is 3%, proportion of substrate to water is 1:0.6, inoculum proportion of three strains is 3 : 3 : 2, inoculum size is 5% and pH is in na-ture.