饮料中腐败酵母菌的分离、鉴定及控制研究

Isolation, Identification and Control of Spoilage Yeast in Beverage

目的:研究饮料变败原因及生产中常用防腐剂对其控制效果,为饮料腐败菌的控制及防腐剂的选择、添加提供理论参考数据。方法:以胀瓶的饮料为研究对象,对分离、纯化所得典型菌落进行菌落形态及细胞特征观察,并采用通用引物NL1/NL4扩增菌株26S rRNA序列进行同源性分析,将其作为供试菌,研究生产中常用防腐剂对其控制效果。结果:从样本中分离获得一株乳白色酵母菌KS01,通过其形态特征及26S rDNA序列的同源性分析,确定该菌株为异常威克汉姆酵母(Wickerhamomyces anomalus);低剂量山梨酸钾和苯甲酸钠均对异常威克汉姆酵母具有显著且持续的抑制效果(P <0.01)。结论:微生物的生长是导致食品腐败变质的根本原因,不同微生物的致腐能力和特征不同。在新型饮料产品(如具有酸性、富氧、含糖等特征的饮料)的研发工作中需谨防因异常威克汉姆酵母污染导致的产品腐败变质,从而实现食品生产安全高效、低成本。

Objective: Study the causes of beverage deterioration and the control effect of common preservatives used in production, then, provide theoretical reference data for the control of beverage spoilage microorganisms and the selection and addition of preservatives. Method: The spoilage yeast in beverage was isolated, purified and identified from the swelling packages via gradient dilution method. The morphology and cell characteristics of typical colonies were observed. The 26S rRNA sequence was amplified with primer NL1/NL4 and sequenced. The homology analysis was then performed. Then, the antibacterial effects of common preservatives on the strain were then investigated. Result: A milky yeast KS01 was isolated from the spoilage beverage. Morphological characteristics and 26S rDNA sequence analysis proved that KS01 was identified to be Wickerhamomyces anomalus. The follow studies showed that both assium sorbate and sodium benzoate exhibited remarkable and sustainable inhibition effect on W. anomalus(P<0.01). Conclusion: The growth of microorganisms is the root cause of food spoilage. Different microorganisms have different abilities and characteristics of causing food spoilage. In the research and development of new beverage products(such as those with acidic, oxygen rich, sugar and other characteristics), it is necessary to guard against product corruption caused by abnormal Wickham yeast pollution, so as to achieve safe, efficient and low-cost food production.