Fermentation of vegetable juice mixture by probiotic lactic acid bacteria

Abstract

Probiotics have several beneficial effects on human health. Probiotic products available on the market today are usually dairy based and cannot be consumed by individuals who suffer lactose intolerance and allergies due to milk proteins. Fruits and vegetables offer healthy alternatives for the production of probiotic foods due to their large distribution and nutritive value. While searching for alternative food matrices, the suitability of bitter gourd (Momordica charantia), bottle gourd (Lagenaria siceraria) and carrot (Daucus carota) juice as a raw material taken for the production of probiotic drinks by lactic acid bacteria (Lactobacillus acidophilus NCDC 11, Lactobacillus plantarum NCDC 414, Pediococcus pantosaceus MTCC 2819) was investigated. The vegetable juice was fermented at 30°C for up to 72 h and changes in the microbial population, pH, sugars and titrable acidity were observed during the fermentation period. The viable cell counts reached up to 8 log CFU/ml, from an initial count of 6 log cfu/ml, and pH decreased from an initial value of 5.2 to below 3.5. The viability of all strains was also determined during the storage time at 4°C within 4 weeks. The viable cell counts of the lactic cultures in the fermented vegetable juice gradually decreased during cold storage. The vegetable juice proved to be a suitable media for the production of a fermented probiotic drink and can serve as a healthy beverage for vegetarians, particularly diabetics.