Effect of peanut butter matrices on the fate of probiotics during simulated gastrointestinal passage

•Peanut butter protected probiotic bacteria during simulated gastrointestinal passage.•Full fat & reduced fat peanut butter offered equal protection to probiotic bacteria.•Probiotics from product N survived better (P < 0.05) than those from products U and C.•Streptococcus/Lactococcus survived better than Lactobacillus and Bifidobacterium.

This study observed the extent to which peanut butter could enhance the viability of selected probiotics during simulated gastrointestinal passage. Full fat and reduced fat peanut butter were inoculated with commercial probiotic product U, N or C at 107 CFU/g. Inoculated products were homogenized in 0.5% NaCl solution. Probiotic products (107 CFU/g) suspended directly in 0.5% NaCl solution served as controls. Digestion in the stomach, upper and lower small intestines was mimicked (each stage for 120 min) with the appropriate enzymes at 37 °C with agitation. Aliquots collected at 30-360 min were enumerated for probiotics. Lower cell populations were observed in samples inoculated with probiotic culture C, followed by U and N (p < 0.05). After 360 min, in peanut butter homogenates, bacterial population from N (5.67 log CFU) was higher than those from U (3.48 log CFU) and C (3.00 log CFU). On average, Streptococcus/Lactococcus species had the highest survivability followed by Bifidobacterium and Lactobacillus species. The fat content of peanut butter did not significantly impact probiotic survivability. Results suggest that peanut butter matrices could protect probiotic bacteria during simulated gastrointestinal passage and could be used as a vehicle for probiotic delivery.