Contribution of post-harvest processing in cocoa bean: Chemometric and metagenomic analysis in fermentation step

Cocoa fermentation is a heterogeneous process, exhibiting a high degree of diversity of flavor, aroma, and microbial communities. A study was conducted to examine cocoa fermentations in five municipalities of a region in Mexico, with the objective of associating post-harvest practices, geographic area, and chemical and microbiological profiles. Through the application of high-performance DNA sequencing, the microbial diversity was identified, and the non-volatile and volatile compounds were identified and quantified by UHPLC-RID/PDA and HS-SPME/GC-MS, respectively. Using PCA, PLS regression and Pearson correlation, post-harvest practices, geographical factors, microbial communities, and volatile and non-volatile compounds were made. The absence of control in cocoa fermentation was associated to Aspergillus, Escherichia, and Bacillus, and reduced the production of essential acids for aroma. This study provides data on the diversity of post-harvest practices and their impact on cocoa quality.