Improving the taste of Ougan ( Citrus reticulate cv. Suavissima ) juice by slight fermentation with lactic acid bacteria

Lactic acid fermentation was applied to Ougan juice (OGJ) for the first time. This study was conducted to improve the taste of OGJ by slight lactic acid fermentation. OGJ was separately fermented at 37°C using Lactobacillus plantarum and Lactobacillus paracasei. Results showed that lactic acid bacteria strains can utilize malic acid as a carbon source, without the consumption of sugar. The observed sugar:acid ratio was highest in the L. plantarum group (3.9) that fermented for 6 hr, and in the L. paracasei group (4.5) that fermented for 12 hr, which resulted in improved sensory acceptance (taste, acidity, aroma, color) of OGJ. Moreover, compared with unfermented OGJ, there were no significant changes (p > 0.05) in total phenolics, total flavonoids, and ascorbic acid (Vc) content in the fermented Ougan juice (FOGJ). Slight lactic acid fermentation also improved the antioxidant activity of OGJ. In particular, neohesperidin and poncirin significantly decreased in L. plantarum group (p < 0.05), while neohesperidin significantly increased in the L. paracasei group (p < 0.05). Overall, slight fermentation with lactic acid bacteria can be used to improve the taste of OGJ, enhancing its quality to a certain extent. Practical applications This study made full use of the metabolic characteristics of lactic acid bacteria and developed a taste balanced fermented Ougan juice, which were an extension of fruits and vegetables deep processing technology and an exploration of new ideas for the research of fermented fruits and vegetables.