High-Performance Indigenous Lactiplantibacillus plantarum Strains for Enhanced Malolactic Fermentation and Wine Quality

Malolactic fermentation (MLF), a key enological process for wine deacidification and aroma and flavor development, is predominantly mediated by lactic acid bacteria. This study characterized 342 indigenous <i>Lactiplantibacillus plantarum</i> (<i>L. plantarum</i>) isolates, a potential starter species underexploited for MLF, from China's Jiaodong Peninsula wine regions through polyphasic analysis. Thirty strains with high tolerance to wine stress conditions and efficient malate metabolism were selected. Among these, two high-performance strains, P101 and J43, exhibited superior MLF kinetics. Their applications had almost no effect on the wine's basic physicochemical parameters, color parameters, and individual phenolic contents. Solid-phase microextraction-gas chromatography-mass spectrometry (SPME-GC-MS) analysis revealed that these strains significantly enhance key aroma compound contents in wines, including ethyl acetate, ethyl lactate, ethyl 2-methylbutyrate, and nerol, contributing more floral and fruity aroma characteristics. These indigenous <i>L. plantarum</i> strains, novel microbial starter cultures, demonstrate dual functionality in enhancing wine quality through controlled fermentation while supporting microbial biodiversity through the development of region-specific strain resources.