蓝莓汁乳酸菌的发酵特性

蓝莓汁中分别接种干酪乳杆菌、保加利亚乳杆菌、植物乳杆菌和嗜酸乳杆菌进行发酵,比较蓝莓汁发酵过程中乳酸菌活菌数、p H值、总滴定酸、总糖、还原糖、总花色苷、总酚、抗氧化能力和色泽等变化。结果表明,蓝莓汁营养丰富,上述各种乳酸菌均能在蓝莓汁中正常生长,发酵24 h,活菌数达8.10 lg cfu/mL以上;此外,植物乳杆菌和嗜酸乳杆菌产酸能力均强于其它两种乳酸菌,可滴定酸含量均超过10.29 g/L,而植物乳杆菌对蓝莓汁中糖的消耗能力最强,总糖的残留量为40.26%;在花色苷和总酚的保留率以及抗氧化能力等方面,植物乳杆菌和嗜酸乳杆菌也要优于其它两种乳酸菌。植物乳杆菌与嗜酸乳杆菌单独发酵和混合发酵时蓝莓汁营养品质的差异分析表明,单独发酵组与混合发酵组在抗氧化能力和总酚的保留上无明显差异,但混合发酵组在花色苷和色泽的保留方面明显优于单独发酵组。综上所述,蓝莓汁应以植物乳杆菌与嗜酸乳杆菌混合发酵为宜。

Fermentation Characteristics of Lactic Acid Bacteria in Blueberry Juice

The blueberry juice was inoculated with Lactobacillus casei, Lactobacillus bulgaricus, Lactobacillus plantarum and Lactobacillus acidophilus to compare the viable bacteria count, pH value, total titration acid, total sugar, reducing sugar, total Anthocyanins, total phenolics, antioxidant capacity and color change respectively. The results showed that the blueberry juice was rich in nutrients, and all the above lactic acid bacteria grew well in blueberry juice. After 24 h of fermentation, the viable counts reached 8.10 lg cfu/mL or more; in addition, the acid-producing abilities of L. plantarum and L. acidophilus were stronger than those of the other two lactic acid bacteria, and the titratable acid reached above 10.29 g/L, while L. plantarum had the strongest ability to consume sugar in blueberry juice, and the residual total sugar was 40.26%; L. plantarum and L acidophilus were also superior to the other two lactic acid bacteria in terms of the retention rate of anthocyanins, total phenols and antioxidant capacity. The difference of nutrient quality of blueberry juice between L. plantarum and L. acidophilus in single and mixed fermentation showed that there was no significant difference in antioxidant capacity and total phenol retention between the two groups, the mixed fermentation group was significantly superior to the single fermentation group in the retention of anthocyanins and color. In conclusion, the mixed fermentation of L. plantarum and L. acidophilus should be suitable for blueberry juice.