PROBIOTIC GRAPE JUICE ADDED WITH PREBIOTIC COMPONENTS: SURVIVAL OF L. casei DURING REFRIGERATED STORAGE AND IMPACT ON THE QUALITY PARAMETERS

The consumption of processed fruit juices has been increasing in the last years, since the population is constantly on the search for healthier foods, which have nutritional and sensorial characteristics that approach to the raw foods and offer practicality to the consumer, providing a better quality of life. The objective of this study was to evaluate the effect of adding a probiotic culture (L. casei) and/or adding oligofructose and polydextrose as prebiotic components to pure grape juice. The products were analyzed for the physicochemical characteristics and sensory acceptance during refrigerated storage (28 days at 7 °C). Natural grape juice (Prat's); oligofructose (P95, Orafti®); polydextrose (Tate & Lyle®); probiotic culture Lactobaciilus paracasei ssp. paracasei (L. casei-01, Christian Hansen®); and plastic containers (60 mL, PET) were used in the experiment. The juices added with probiotics and/or prebiotic fibers showed physicochemical characteristics (pH, titratable acidity, L*, a*, b*, firmness, cohesiveness, consistency and viscosity index) similar to the pure juice (p>0.05). The probiotic culture had a significant influence on the acceptance of the products, decreasing it for most of the evaluated attributes. The product added with polydextrose was the least accepted juice. The addition of oligofructose caused an improvement in the acceptance of the probiotic product in the aroma and flavor attributes, making it similar (p> 0.05) to that of the pure product. However, the juice with oligofructose was still less accepted than the pure product in texture and general attributes (p≤0.05). The scores obtained were greater than 6 on a 9-point scale for all attributes and formulations, indicating that consumers liked the products slightly. The acceptability index was higher than 70%, indicating potential commercialization. All formulations presented counts higher than 106 CFU/mL during the 28 days of refrigerated storage and may be considered probiotic products. It is concluded that it is possible to develop grape juice added with L. casei as a probiotic culture and prebiotic fibers that present physicochemical characteristics, viability of the probiotic culture and adequate sensorial acceptance and that can be stored for 28 days at 7oC in plastic packages.