乳酸菌剂对胡萝卜青贮品质及营养成分的影响

Effects of Lactic Acid Bacteria Preparation on Quality and Nutrient Composition of Carrot Silage

【目的】分析乳酸菌剂对胡萝卜青贮品质及营养成分的影响,为筛选提高胡萝卜青贮品质的乳酸菌添加剂提供参考依据。【方法】以切丝后的胡萝卜为原料,分别添加L1、L2、L3、L4、L5和L6乳酸菌剂进行青贮饲料调制,以不使用乳酸菌进行青贮为对照(CK),测定不同乳酸菌剂处理的胡萝卜青贮饲料感官评价指标及青贮的微生物数量、化学成分和活性成分。【结果】添加乳酸菌剂能控制胡萝卜青贮的pH在4.0以下,使胡萝卜基本保持原来的颜色和质地;添加乳酸菌剂可提高胡萝卜青贮发酵中乳酸菌的增殖速度和数量,其中在青贮32 d时添加L1、L2、L3、L4、L5和L6乳酸菌剂青贮的乳酸菌数量分别比CK显著增多24.7×10^5、23.2×10^5、22.7×10^5、6.8×10^5、9.7×10^5和7.2×10^5 CFU/mL(P<0.05),且能控制霉菌的数量在20.00 CFU/mL水平;添加乳酸菌剂能有效提高胡萝卜青贮的有机物含量,有效维持较低的氨态氮含量;相比于CK,添加L2乳酸菌剂胡萝卜青贮的胡萝卜素、维生素C和总酚含量等活性成分可得到有效保存。【结论】从青贮发酵过程中胡萝卜感官评定指标、乳酸菌数量、氨态氮含量和活性成分含量等方面综合考虑,L2可作为提高胡萝卜青贮饲料品质的乳酸菌剂。

【Objective】The effects of lactic acid bacteria inoculants on quality and nutrient composition of carrot silage were studied in order to provide the reference for selecting lactic acid bacteria inoculants that could improve the the quality of carrot silage.【Method】The silage material were carrot which was cut,silage was prepared with different lactic acid bacteria agents,which were L1,L2,L3,L4,L5 and L6 lactic acid bacteria agents group and blank group as control(CK),respectively.The effects of different lactic acid bacteria agents on the sensory evaluation index of carrot silage and the number of microorganisms,chemical composition and active ingredients in the silage were determined.【Result】The results showed that the addition of lactic acid bacteria could keep the pH value under 4.0 of raw materials and keep the original color and texture of carrot basically.Silages with LAB could increase the growth rate and quantity of lactic acid bacteria in the fermentation of carrot silage,lactic acid bacteria number of silage added L1,L2,L3,L4,L5 and L6 lactic acid bacteria agents at 32 d of silage significantly increased 24.7×10^5,23.2×10^5,22.7×10^5,6.8×10^5,9.7×10^5 and 7.2×10^5 CFU/mL compared to CK(P<0.05),controlling the number of lactic acid bacteria in the range of 20.00 CFU/mL.Silages with LAB could inhibit the proliferation of mould,controlling the number of moulds in the range of 20.00 CFU/mL;Silages with LAB could obtain more organic matter content of carrot.Compared with the control group,silages with LAB could effectively retain the content of carotene,vitamin C and total phenol.【Conclusion】Combined with the sensory quality,lactic acid bacteria number,ammonia nitrogen content and active ingredient content,adding L2 lactic acid bacteria agent had beneficial effects on improving the quality of carrot silage.