不同发酵剂对发酵驴乳酸奶在冷藏期间品质的影响

目的研究不同发酵剂发酵的驴乳酸奶在冷藏期间的品质变化。方法对使用3种发酵剂发酵的驴乳酸奶在冷藏期间微生物指标、理化指标和风味滋味进行检测及感官评价。结果在冷藏26 d中, LR-A、LR-B乳酸菌活菌数显著降低,LR-C乳酸菌活菌数逐渐增多,细菌菌落总数均呈现先上升后下降的变化趋势;随着冷藏时间的延长, LR-A、LR-B和LR-C的pH值持续降低,总酸度持续上升,持水力降低,感官评价分析3种驴乳酸奶在第14 d时口味最佳,之后都有所下降。结论 LR-A、LR-B在冷藏至26 d时各项指标符合国标要求,仍可以正常饮用, LR-C在冷藏14 d后酸度上升太高,超出接受范围无法饮用。

Effects of different starters on the quality of fermented donkey milk yogurt during cold storage

Objective]In order to study the quality change of donkey milk yogurt fermented by different starters during cold storage,.Methods] The microbial index, physical and chemical index, flavor taste of donkey milk yogurt fermented by three kinds of starter during cold storage were detected and sensory evaluation was carried out.Results] During the 26-day cold storage, the number of live lactic acid bacteria in LR-A and LR-B decreased significantly, LR-C increased gradually, and the total number of bacterial colonies showed a trend of increasing first and then decreasing. With the extension of cold storage time, the pH values of LR-A, LR-B and LR-C decreased continuously, the total acidity increased continuously, and the water holding capacity decreased. Sensory evaluation showed that the three donkey milk yoghurts had the best taste on the 14th day, and then all declined.Conclusion] LR-A and LR-B can still be drunk normally after being refrigerated for 26 days, and the acidity of LR-C rises too high after being refrigerated for 14 days, which is beyond the acceptable range.