Effects of Faba Bean (Vicia faba L.) Flour on Viability of Probiotic Bacteria During Kefir Storage

Whole ground faba bean was investigated for its capability and efficiency to enhance bacterial survival and growth during kefir storage. Microbial analyses, pH and total titratable acidity (TTA) were measured in kefir samples, containing starter cultures with or without probiotic bacteria, (Lactobacillus acidophilus and Bifidobacterium lactis) supplemented with whole ground faba bean during 28 days cold storage at 4 ºC. Faba bean flour supplementation (4%) stimulated bifidogenic microbial growth, increased titratable acidity linearly from day 1 to 21, and reduced pH during kefir storage. Bacterial count was strongly and positively correlated with lactic acid content and inversely associated with pH. Faba bean contributed to the additive effect on viable cell counts and pH of the probiotic co-culture (Lb. acidophilus and B. lactis), but had a distinct antagonistic effect on titratable acidity of kefir. Hierarchical cluster analysis based on the microbiological, titratable acidity and pH data differentiated kefir corresponding to the presence or absence of faba bean supplementation. Faba bean flour maintain sprobioticst ability and extends kefir shelf life.