鲜龙眼果肉的干酪乳杆菌发酵特性的研究

Fermentation characteristic of Lactobacillus casei in fresh longan pulp

研究了鲜龙眼果肉接种干酪乳杆菌发酵后干酪乳杆菌活菌数、p H值、糖组分、有机酸组分、多糖、黏度、总多酚、ORAC值和色泽等变化。结果表明,鲜龙眼溶液营养丰富,干酪乳杆菌能在鲜龙眼汁中很好的生长,发酵12 h,菌量达到109 cfu/m L以上。蔗糖是龙眼果肉中主要糖组分,干酪乳杆菌能够很好地利用鲜龙眼中的蔗糖,将其转化为胞外多糖,导致发酵液的黏度明显升高。发酵12 h后,胞外多糖的含量高达1.5 g/100 g。同时,随着发酵的进行,乳酸菌含量逐渐升高,导致发酵液的p H明显下降。此外,乳酸菌发酵导致发酵液的总多酚含量和ORAC值出现明显增加。

In this study, changes of counts of Lactobacillus casei, pH value, sugars, organic acids, exopolysaccharides, total polyphenols, viscosity, ORAC value, color, and so on during the fermentation of fresh Iongan pulp were investigated. Results showed Lactobacillus casei can grow well in the Iongan pulp, which reached more than 109 cfu/mL after 12 h. Sucrose is the main sugar in the fresh Iongan pulp, and Lactobacillus casei can transform the sucrose into exopolysaccharides, which resulted in the increase of viscosity. The content of exopolysaccharides in the fermentation broth reached 1.5 g/100 g after 12 h. The content of lactic acid bacteria increased with the increase of fermentation times, which caused the pH of fermentation broth to decrease. In addition, the contents of total polyphenol and the ORAC value increased during the fermentation of Iongan pulp with Lactobacillus casei.