Effects of fermentation on the quality characteristics and biological activities of citrus juices

In this study, physicochemical, microbiological qualities and biological activities of fruit juices obtained from three different citrus fruits and fermented products obtained as a result of inoculation of nine different lactic acid bacteria were investigated. As a result of the research, was determined that titration acidity, free radical scavenging activity and total phenolic substance values increased due to fermentation process, whereas pH, aw, dry matter, viscosity, brix and L* values decreased. Among the samples, the lowest DPPH value was determined by B. animalis spp.lactis inoculation, and the highest total phenolic content value was found in the samples obtained by L. plantarum inoculation among three citrus species. Moreover, it was determined that the antibacterial and antifungal effects of the obtained products increased on the strains used in the study, especially with fermentation. It was determined that the antibacterial effect is more effective on Gram (-) bacteria in general.