Enhancing jujube juice quality through Lactiplantibacillus plantarum fermentation: a metabolomics approach

Jujube, a nutrient-rich fruit high in fructose and glucose, presents a valuable substrate for fermentation by Lactiplantibacillus plantarum. However, the specific metabolic mechanisms influencing L. plantarum's impact on jujube juice quality remain unclear. This study utilized the high-performance strain LP-CWC-Zao for jujube juice fermentation, comprehensively profiling volatile and non-volatile metabolites via gas chromatography-mass spectrometry (GC-MS) and ultra-high-performance liquid chromatography coupled to a Q Exactive TM HF-X (UHPLC-Q Exactive HF-X). The findings revealed that LP-CWC-Zao demonstrated excellent fermentation characteristics and antioxidant activity, with 40 h identified as the optimal fermentation period. Significant metabolic changes occurred at 16-20 h and 36-40 h. Fermentation notably increased (p < 0.05) levels of key volatile metabolites, including acids, esters, phenols, and terpenes, particularly ethyl benzoate. Moreover, it enhanced non-volatile metabolites such as phenylpropanoids and coumarins, enriching the juice's flavor and imparting medicinal, antibacterial, and antioxidant properties while maintaining the stability of bioactive compounds.