Abstract
Lactic acid bacteria (LAB) fermentation has been shown to improve the nutritional and functional activity of grains. The aim of this study was to investigate the changes in physicochemical properties, antioxidant activity, hypoglycaemic activity and metabolites of maize juice after fermentation with two species of Lactobacillus L. plantarum HH-LP56 and L. acidophilus BNCC336636. The non-targeted metabolomics analysis based on UHPLC-Q-TOF-MS metabolomics method was performed to reveal the metabolic mechanism of corn juice. Compared with the unfermented sample, lactic acid fermentation increased corn juice's antioxidant activity and hypoglycemic activity. Both fermented samples and their unfermented counterparts yielded a total of 2890 metabolites, of which 296 differential metabolites were detected. These metabolites were primarily concentrated organic acids and derivatives, lipid-like molecules, and organic oxygen compounds. Lactic acid fermentation significantly changed the metabolite composition and enhanced the biological activity of corn juice, which provides a theoretical basis for the processing and utilisation of maize. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s10068-025-01853-8.