Effect of different killing methods during curing on the phytochemical and bacterial composition of Vanilla planifolia using multi-omic approaches

<i>Vanilla planifolia</i> Jacks. ex Andrews, is cultivated for its aromatic pods, obtaining the primary source of vanillin, a molecule valued for its flavor and bioactivity. Mexico ranks among the top five global producers, and Papantla, Veracruz, contributes 70 % of national production. Developing vanilla's characteristic aroma involves a curing process composed of killing, sweating, drying, and conditioning, which enzymatic reactions and microbial activity play essential roles. This study assessed the impact of four killing treatments: microwave, hot water immersion, sonication, and freezing on the phenolic composition and bacterial communities in vanilla curing through metabolomic and 16S sequencing approaches. Freezing treatment resulted in the most substantial changes in phenolic profiles, including higher vanillin concentrations. <i>Bacillus</i> was the dominant bacterial genus, with hot water immersion and sonication showing the greatest α-diversity. These findings underscore the value of omic sciences in refining curing processes, enabling producers to achieve higher-quality vanilla through more efficient and technical methods.