Preparation of a synbiotic low lactose non-fermented and fermented drinking dessert containing lactic cheese whey

In this study, a synbiotic drinking dessert containing lactic cheese whey was prepared using Lactobacillus paracasei and Lactobacillus rhamnosus GG as low-lactose non-fermented and fermented forms. The results showed that the fermentation process of these two bacteria is too slow, compared with other probiotic bacteria. After about 24 hours of incubation, the pH of samples containing L. paracaei was 5.2 and L. rhamnosus GG was 5.6. The results of pH and acidity analysis showedsucrose in both samples and glucose produced by enzymatic hydrolysis in non-fermented samples caused acid production and consequently reduction of pH of samples during cold storage. The most reduction in pH of both fermented and non-fermented samples was related to samples containing L. paracasei. As pH decreased, acidity increased, indicating that the drinking dessert compounds had no buffering properties. The reduction of the probiotic population in non-fermented samples after 7 days of storage in the refrigerator was not significant (p>0.05). In fermented samples, the probiotic count was almost constant in the refrigerator after 21 days of storage. In both fermented and non-fermented samples, the probiotic count was higher than108CFU/ml, indicating that the composition and nature of drinking dessert which had high viscosity, could support the survival of probiotic bacteria. The sensory evaluation also showed in both fermented and non-fermented groups, the sample containing L. rhamnosus GG had a higher overall acceptability and the overall acceptability of non-fermented samples was higher than overall acceptably of fermented form.