不同乳酸菌组合对发酵液体饲料品质的影响

Effect of Different Lactobacillus Forms on Quality of Fermentation Liquid Feed

本试验用液态发酵法研究不同菌种来源对乳酸菌发酵液体饲料(fermentation liquid feed,FLF)感官、pH和菌落计数的影响,分别以乳酵素(Lactobacillus enzymes,LE)、乳酵素+基础料(enzymes mixture,EM)、5 mg/kg乳酸菌种+基础料(spawn mixture,SM)和空白对照组(control,CON)作为研究对象,所有发酵罐保持发酵底物∶水=1∶3,(36±1)℃恒温发酵192 h,每隔24 h做1次感官评定和pH测定;取发酵72 h的样品进行培养,分别计数培养48和72 h的菌落。结果表明,EM和SM均具有良好的感官性能,保质期长,其活菌落计数均极显著高于LE与对照组(P<0.01),但EM与SM相比差异不显著(P>0.05);各组的pH均先降低后升高,LE处理组pH显著(P<0.05)或极显著(P<0.01)低于其他试验组。提示,LE发酵方式不能改善FLF品质,EM和SM发酵方式的饲料品质优于LE,EM与SM发酵效果类似。

The objective of this research was to investigate the effect of different Lactobacillus sources on sensorial evaluation, pH and bacterial colony forming unit （CFU） in fermentation liquid feed （FLF）. Fermentation liquid Lactobacillus enzymes （LE）, fermentation liquid Lactobacillus enzymes mixture （EM） and 5 mg/kg of fermentation liquid Lactobacillus spawn mixture （SM） were designed as trial groups, respectively, and fermentation liquid substrate as a control （CON）. All groups above maintained a fermentation substrate to water ratio as 1：3, and kept at （36±1）℃ thermostatically for 192 hours. Sensorial evaluation and pH measurement were conducted daily, and samples were obtained after 72 h of fermentation and then cultured. CFU was counted at 48 and 72 h after culturing, respectively. The results showed that EM and SM had superior sensorial characteristics, longer shelf lives, and had extremly significantly more colony counts than LE and CON （P〈0.01）, whereas there was no significant differences in CFU between EM and SM （P〉0.05）. The pH of all treatments showed a U curve and pH of LE was significantly （P〈0.05） or extremly signifrcantly （P〈0.01） low compared to other treatments. The results proved that LE could not improve fermentative quality of FLF, both EM and SM improved quality of FLF.