凤窝酒曲酵母菌多样性及其分离株发酵红枣酒氨基酸组成分析

采用野生蓝靛果（Lonicera caerulea）纯化得到花青素，以生长曲线、抑菌圈直径、最小抑菌浓度为评价指标，研究其对嗜热链球菌（Streptococcus thermophilus）、保加利亚乳杆菌（Lactobacillus bulgaricus）生长的影响，分析其抑菌效果、抑菌机理及保质期21 d内酸度、pH值、还原糖的变化。结果表明，添加花青素组能抑制菌株生长；花青素对两种乳酸菌及其混合菌有一定的抑制作用，对嗜热链球菌、混合菌（1∶1）及保加利亚乳杆菌的最小抑菌浓度分别为62.5 μg/mL、62.5 μg/mL、31.25 μg/mL；加热预处理、培养基pH以及糖浓度对花青素的抑菌作用产生影响。花青素对乳酸菌的抑菌作用机理是其改变细胞膜通透性、损伤菌体蛋白引起菌体蛋白的泄露。0.32%花青素添加量可抑制酸奶后酸化作用。

Yeast diversity of Fengwo Jiuqu and amino acid composition of jujube wine fermented by their isolates

Yeast strains were isolated and identified from Fengwo Jiuqu, and the results indicated that 45 isolates were identified as 8 species, namely Pichia anomala, Candida glabrata, Cyberlindnera fabianii, Saccharomyces cerevisiae, Candida tropicalis, Pichia kudriavzevii, Clavispora lusitaniae, and Saccharomycopsis fibuligera. Jujube wine was fermented by S. fibuligera and S. cerevisiae strains, and the types and contents of amino acids in wine composition were studied. The results indicated that 12 types of amino acids were detected in jujube wine, and the content was 3.02 mg/ml. Among them, the contents of proline and aspartic acid were the highest, which were 1.66 mg/ml and 0.74 mg/ml, respectively. The contents of sweet and sour amino acids (2.03 mg/ml and 0.74 mg/ml) were the highest in jujube wine, accounting for 67.1% and 24.4% of the total, respectively. Meanwhile, the umami, bitter and astringent amino acids contents were relatively lower.