Effect of inoculation with <em>Weissella paramesenteroides</em>&amp;nbsp;and <em>Lactiplantibacillus plantarum</em>on soy sauce fermentation

This study aimed to investigate the effect of inoculation with <em>Weissella paramesenteroides&nbsp;</em>and <em>Lactiplantibacillus plantarum</em>&nbsp;on the quality of soy sauce. Three inoculation strategies were evaluated, the analysis&nbsp;results&nbsp;of flavor&nbsp;components&nbsp;and&nbsp;biogenic&nbsp;amine&nbsp;(BA)&nbsp;levels&nbsp;suggested&nbsp;that&nbsp;the&nbsp;optimal strategy&nbsp;for&nbsp;soy&nbsp;sauce&nbsp;fermentation&nbsp;was&nbsp;to&nbsp;inoculate <em>W. paramesenteroides</em><em>&nbsp;</em>on&nbsp;day 1&nbsp;(1.0 × 106&nbsp;CFU/g),&nbsp;and&nbsp;<em>L. plantarum</em><em>&nbsp;</em>on&nbsp;day&nbsp;7&nbsp;(1.0 × 106 CFU/g).&nbsp;This&nbsp;enhanced&nbsp;its&nbsp;organic acids (1.47-fold), volatiles (1.29-fold), and free&nbsp;amino&nbsp;acids&nbsp;(1.21-fold)&nbsp;flavors. It demonstrated a superior 2-Methoxy-4-vinylphenol production capacity and characteristic flavor&nbsp;components such as lactic acid, 1-octen-3-ol, benzeneacetaldehyde, and glutamic acid were increased by 1.38-, 1.45-, 4.10-, and 1.37-fold, respectively.&nbsp;Besides, the content of BA was reduced by 42.26%, and most of them were positively correlated with their precursors, suggesting that the addition of <em>W. paramesenteroides </em>and <em>L. plantarum</em>&nbsp;inhibited the growth of microorganisms involved in BA synthesis or degraded it.&nbsp;This work provides valuable information for the exploration and industrial application of functional microorganisms in soy sauce fermentation.