柑橘渣生产蛋白饲料的发酵工艺筛选

Screening of fermentation technology for producing protein feed from citrus pomace

试验旨在研究柑橘渣最佳发酵工艺条件。试验以柑橘渣为原料,以发酵产物中的粗蛋白含量为考核指标,采用单菌发酵试验预筛选产蛋白量较高的优势菌株,将预筛选的优势菌株按1∶1∶1∶1进行混合发酵;对发酵基质比例、菌液的接种量、发酵时间进行正交分析,优化柑橘渣的发酵工艺条件。结果显示:黑曲霉、热带假丝酵母、植物乳杆菌和枯草芽孢杆菌为单菌种发酵试验的较优菌种;在黑曲霉∶热带假丝酵母∶植物乳杆菌∶枯草芽孢杆菌按1∶1∶1∶1比例接种,尿素添加量为1.5%条件下,柑橘渣发酵最适工艺条件为发酵基质柑橘渣与麸皮的比例7∶3、接种量20%、发酵时间8 d。研究表明,在此优化工艺条件下,柑橘渣发酵所得的蛋白质饲料产物的粗蛋白质含量较高,能够提高柑橘渣的利用价值和经济效益。

The experiment was to study the optimum fermentation conditions of citrus residue. Using citrus residue as raw material and crude protein content in fermentation products as evaluation index, the dominant strain with higher protein production was pre-screened by single-bacteria fermentation test, and the pre-screened dominant strain was mixed with1∶ 1∶ 1∶ 1 fermentation. Orthogonal analysis was carried out on proportion of fermentation substrate, inoculation amount of bacteria liquid and fermentation time to optimize the fermentation conditions of citrus residue. The results showed that Aspergillus niger, Candida tropicalis, Lactobacillus plantarum and Bacillus subtilis were the best strains in single strain fermentation test. Under the conditions of Aspergillus niger, Candida tropicalis, Lactobacillus plantarum and Bacillus subtilis at the inoculation ratio of 1∶1∶1∶1 and urea dosage of 1.5%, the optimal fermentation conditions were the ratio of citrus pomace to bran 7∶3, the inoculation amount 20%, and the fermentation time 8 d. The study indicates that under the optimized conditions, the crude protein content of protein feed products obtained from citrus residue fermentation is the highest, which can improve the utilization value and economic benefit of citrus residue.