Abstract: Grapefruit juice was debittered by cleaving the bitter compound naringin through fermentation with lactic acid bacteria with strong ability to metabolize functional oligosaccharide. The experimental results showed that the content of naringin in the fruit juice was reduced by Lactiplantibacillus plantarum 1-1-2 fermentation, while the content of naringenin was significantly increased, and the content of total phenols and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging capacity were also significantly increased. DPPH radical scavenging activity was positively correlated with the contents of total phenols and naringenin. These findings prove that L. plantarum 1-1-2 can hydrolyze naringin into naringenin, with significantly higher antioxidant activity. The sensory evaluation score of fermented grapefruit juice was higher than that of unfermented grapefruit juice. This study can provide a theoretical basis for improving the taste of grapefruit juice and developing functional probiotic fermented products.

Key words: grapefruit; Lactiplantibacillus plantarum 1-1-2; debittering; naringin; naringenin; antioxidant capacity