Probiotification of Whole Grape Juice by Water Kefir Microorganisms

Abstract

: Probiotics are live microorganisms that when ingested in adequate amounts help in the balance of the intestinal microbiota. Kefir is considered a probiotic beverage associated with the improvement of several pathologies. Fruit juices are considered an excellent culture medium for these microorganisms, presenting nutrients that favor microbial growth. This work aimed to prepare a probiotic drink from the fermentation of whole grape juice by microorganisms from the water kefir. Different amounts of kefir grains were tested (5, 10, 20, 30, 40, 50, and 60 g) in 500 mL of grape juice. The fermentation processes were developed under static conditions at room temperature for 24 h. Seven formulations were tested for physical-chemical and microbiological analyses. A questionnaire on the knowledge and consumption of probiotics was applied to the academic community. Three formulations were selected for sensory analysis and stored under refrigeration. All formulations showed growth of lactic acid bacteria and no reduction in storage viability. A significant reduction in soluble solids was observed in all formulations, and an increase in acidity and pH formulations with 5 and 20 g of kefir, respectively. About 64% of the participants reported knowing the definition of probiotics. In addition, a low intake of this product was observed. The formulation with 5 grams of water kefir grains was better accepted by the consumers when compared to the others. Thus, grape juice can be a great alternative to consume probiotic microorganisms, especially for those who do not consume dairy products.