Honey varietals differentially impact Bifidobacterium animalis ssp lactis survivability in yogurt through simulated in vitro digestion

Abstract

BackgroundBifidobacterium animalis ssp. lactis DN-173 010/CNCM I-2494 (B. animalis) is a probiotic strain commonly added to yogurt. Yogurt and honey are a popular culinary pairing. Honey improves bifidobacteria survival in vitro. However, probiotic survival in yogurt with honey during in vitro digestion has not been investigated. ObjectiveThe study aimed to evaluate the effects of different honey varietals and concentrations on B. animalis survivability in yogurt through in vitro digestion. MethodsYogurt with honey or control-treated samples underwent in vitro simulated oral, gastric, and intestinal digestion. B. animalis cells were enumerated on MRS medium followed by an overlay with a modified selective MRS medium; all underwent anaerobic incubation. B. animalis were enumerated pre-digestion and after oral, gastric, and intestinal digestion. There were two study phases: phase 1 tested four honey varietals at 20% w/w per 170g yogurt, and phase 2 tested seven dosages of clover honey (20, 14, 10, 9, 8, 6, and 4% w/w) per 170g yogurt. ResultsSimilar B. animalis counts were observed between all treatments after oral and gastric digestion (<1 Log CFU/g probiotic reduction). Higher B. animalis survivability was observed in yogurt with clover honey after exposure to simulated intestinal fluids ([~]3.5 Log CFU/g reduction; P < 0.05) compared to all control treatments ([~]5.5 Log CFU/g reduction; P < 0.05). Yogurt with 10 to 20% w/w clover honey increased B. animalis survivability after simulated in vitro digestion (up to [~]4.7 Log CFU/g survival; P < 0.05). ConclusionYogurt with added honey improves probiotic survivability during in vitro digestion. The effective dose of clover honey in yogurt was 10 to 20% w/w per serving (1 - 2 tablespoons per 170g yogurt) for increased probiotic survivability during in vitro digestion.