Investigation of volatile compounds during fermentation of Elaeagnus moorcroftii Wall.ex schlecht. juice by Bifidobacterium animalis subsp. lactis HN-3 and Lacticaseibacillus paracasei YL-29

The influence on and biotransformation of volatile compounds (VOCs) during fermentation of Elaeagnus moorcroftii Wall.ex Schlecht. juice (EWSJ) through single inoculation and co-inoculation of Bifidobacterium animalis subsp. lactis HN-3 (B.an3) and Lacticaseibacillus paracasei YL-29 (L.cp29) were analyzed through headspace-solid phase microextraction-gas chromatography-mass spectrometry. Compared with the B.an3- and L.cp29-fermented EWSJ, the B.an3 + L.cp29-fermented EWSJ had more increased 9 desirable flavor compositions and less decreased in or even elimination of 12 undesirable flavor compositions, and 3 new characteristic VOCs, formed through the interaction between B.an3 and L.cp29 were detected. In addition, biotransformations that led to an increase and a decrease in VOCs mainly involved 3 oxidation, 3 reduction, 1 hydrolysis, and 1 isomerization reactions. This study offers a theoretical basis for investigating the interaction effect of Lactobacillus and Bifidobacterium species on VOCs and developing lactic acid bacteria-fermented plant-based juices with lower sugar content and better flavor.