Effects of 2′‐fucosyllactose on the viability of starter cultures and Bifidobacterium strains of human origin in yogurt during refrigerated storage

Abstract

Abstract2′‐Fucosyllactose (2′‐FL) is postulated to provide health benefits and promote the growth of probiotics. This work was undertaken to study the effects of 2′‐FL on the viability of starter cultures and Bifidobacterium strains of human origin in yogurt during refrigerated storage. Yogurts were produced containing 2′‐FL (0 or 2 g/L) and Bifidobacterium strains of human origin (Bifidobacterium longum subsp. longum BB536 or Bifidobacterium longum subsp. infantis ATCC 15697) at a concentration of at least 109 CFU/mL. All yogurts were stored at 4°C for 5 weeks. Results showed that 2′‐FL was stable in yogurts for at least 5 weeks of cold storage, and the addition of 2′‐FL did not significantly alter yogurt fermentation parameters, associated metabolites, and the viability of mixed yogurt starter cultures and Bifidobacterium strains (p > 0.05). The addition of bifidobacteria had a negative impact (p < 0.05) on the survival rate of starter cultures, Streptococcus thermophilus and Lactobacillus delbureckii subsp. bulgaricus. Meanwhile, it is difficult to maintain a high survival rate of bifidobacteria in final yogurt products, and the addition of 2′‐FL could not enhance the viability of bifidobacteria. B. longum BB536 survived at a level higher than 106 CFU/g for 28 days, while B. infantis ATCC15697 maintained this level for only 7 days. In summary, this study has shown the impact of 2′‐FL and bifidobacterial species on yogurt properties, and results suggest that it is promising to use 2′‐FL in yogurt products as a prebiotic.Practical ApplicationYogurt is known for its beneficial effects on human health and nutrition. This study reported the production of symbiotic yogurt containing bifidobacteria and 2′‐fucosyllactose (2′‐FL) as a functional food for specified health uses. The viability of yogurt starter cultures and probiotic bifidobacterial strains was analyzed in this study. Moreover, this research demonstrated that 2′‐FL could be added to yogurt without affecting the characteristics of yogurt significantly.