柑橘皮渣发酵蛋白质饲料(SCP)工艺优化及光照对发酵饲料的影响

目的]探求柑橘皮渣的资源化利用方式。方法]以柑橘废渣为主料,麸皮为辅料,通过固态发酵技术生产单细胞蛋白饲料,从热带假丝酵母(Candida tropicalis)、康宁木霉(Trichoderma konigii)、米曲霉(Aspergillus oryzae)、球拟圆酵母(Torulopsis globosa)4株菌中,优选出效果最佳的菌株,并优化菌株最佳混合比例。结果]确定T.konigii∶C.tropicalis∶A.oryzae最优比例为2∶2∶1,发酵时间84 h,温度33℃,含水率70%,菌液接种量0.4 m L/g,发酵后粗蛋白含量达到35.03%,粗脂肪含量达到4.92%,同时粗纤维含量为12.08%。另外,通过光照强度对发酵饲料的影响试验可知,光强在1 000~2 500 lx时,可以促进微生物生产蛋白质和脂肪,当光强为10 000 lx时,微生物生产蛋白质和脂肪的能力受到抑制;另外,光照条件不利于粗纤维的降解。光照条件对非光合微生物发酵饲料既有促进作用又有抑制作用。结论]该研究可为柑橘皮渣废弃物的资源化利用提供重要的理论指导。

Process Optimization of SCP Fermented from Citrus Wastes and Influence of Light Intensity on SCP

Objective] Efficient utilization way of citrus wastes was explored.Method] Taking citrus wastes as raw materials,combined with agricultural by-product wheat bran as auxiliary material to produce single cell protein (SCP)feed.Candida tropicalis,Trichoderma konigii,Aspergillus oryzae,Torulopsis globosa were used as fermentation strains,optimum strain and mixing ratio were studied.Result] The best strains mixed proportion for fermentation was C.tropicalis:T.konigii:A.oryzae =2∶ 2∶ 1.One-variable method was used to optimize fermentation conditions.The experiment conditions were as follows:fermentation time 84 h;fermentation temperature 33 ℃;moisture content 70 ％;microbial added concentration 0.4 mL/g.The crude protein,crude fat and crude fiber content were 35.03％,4.92％ and 12.08％ respectively.In addition,the influence of light intensity on fermentation feed indicated that when light intensity was 1 000-2 500 lx,the production capacity of protein and fat by microbial were promoted;as light intensity was 10 000 lx,the production capacity of protein and fat by microbial were restrained.In addition,illumination had both acceleration and inhibition on non-photosynthetic microorganism for fermentation of feed.Conclusion]The research can provide an important theoretical guidance of citrus waste recycling utilization for agriculture.