Effect of passion fruit by-product and fructooligosaccharides in the growth and folate production by Lactobacillus spp. in fermented soymilks using tri-enzymatic method

ALBUQUERQUE, M.A.C.; SAAD, S.M.I.; BEDANI, R.; SILVA VIERIRA, A.S.; LEBLANC, JEAN GUY

Simposio; 12th Symposium on Lactic Acid Bacteria; 2017

Bio-enrichment of foods with natural folates produced by microorganisms during fermentation is a healthy alternative to the mandatory programs of some countries that use folic acid (the chemically synthesized form of folate) to fortify foods. Soy-based foods are good source of nutrients and known for its functional characteristics, besides, soy products are an interesting alternative to dairy foods consumption. Thus, the ability of four commercial probiotic lactobacilli (Lb. acidophilus LA-5, Lb. rhamnosus LGG, Lb. fermentum PCC, Lb. reuteri RC-14) to grow and produce folates during fermentation of four soymilk formulations (soymilk (SM); SM with 1% (m/v) of passion fruit by-product (PF); SM with 1% of fructooligosaccharides (FOS); SM with 0.5% of PF and 0.5% of FOS) was evaluated. Each strain was inoculated (4-5 log cfu/ml) in each SM formulation as pure culture and incubated at 37 °C for 24 h. Samples were taken at 0 and 24 h, treated enzymatically with amylase, protease and human plasma and the folate content determined using a microbiological assay. All lactobacilli strains were able to ferment all soymilks except Lb. reuteri RC-14 that only grew in SM with PF. Additionally, all strains was able to produce folate during soymilks fermentation and SM+PF+FOS showed the best impact on microbial folate production where Lb. fermentum PCC showed the highest production of the vitamin. The folate production was strain dependent and also influenced by the composition of each soymilk.