Evaluation of the Effect of Lactobacillus acidophilus and Bifidobacterium lactis Bacteria on Vitamin B2 and B3 Contents of Yogurt During Refrigeration by the Application of High Performance Liquid Chromatography

The interest in probiotic products have been increased recently by the consumers. Milk and dairy products are natural sources of B group vitamins in the human diet. This study was carried out in order to investigate the level of riboflavin (vitamin B2) and niacin (vitamin B3) in probiotic yogurt and the results were compared with the traditional yogurt during refrigerated storage.

After preparation of conventional and probiotic yogurts، all the samples were stored at 4°C، and the contents of B2 and B3 vitamins were assessed on the first، third and seventh day of refrigeration. Vitamins B2 and B3 were analysed using highperformance liquid chromatography by fluorescence and ultraviolet detections respectively. Data was analysed using SPSS version 18.

Vitamin B2 contents of probiotic yogurt samples were significantly higher than the control samples during the course of this study (P< 0. 05). Significant differences between vitamin B3 contents in conventional and probiotic yogurt samples were found on the seventh day of refrigeration (P< 0. 05).

This study showed that by using probiotic strains higher retention of B2 and B3 vitamins in yogurt during refrigerated storage is observed.