Investigation of potential prebiotic activity of rye sprout extract

Rye (Secale cereale) is one of a number of cereal species that grow wild in the northwest of Iran, Turkey, and Central Asian countries. It is revealed that sprouts possess higher vitamins, antioxidant, flavonoids and fiber than grains. For evaluation of the potential prebiotic activity of rye sprout extract (RSE), the grains were soaked in water, germinated and dried by a freeze-dryer. The in-vitro viability and relative growth ratio (RGR) of probiotic bacteria, as well as their antimicrobial activities and their retention in synbiotic yogurt during 56 days cold storage in presence of RSE, were investigated. The sensory properties (odor, color, texture, taste and overall acceptance) of symbiotic yogurt with different amounts of RSE in comparison with control group were evaluated. The results showed that adding various concentrations of RSE increased the viability of both Lactobacillus acidophilus and Bifidobacterium animalis (p<0.05), although this increase in B. animalis was better than L. acidophilus. Comparison of RGR of treated samples indicated that adding RSE even 0.25% can increase the growth and survival of probiotic in comparison with control. The results also showed that adding of RSE promoted the antimicrobial activities of probiotics. In synbiotic yogurt, probiotic populations remained higher than the minimum recommended therapeutic dose for an extended period of cold storage. There was no significant difference between sensory parameters of control specimens and synbiotic yogurt. According to our results, the synbiotic effect of RSE and probiotics highlights the potential application of RSE as a prebiotic in dairy and other functional products.