Analysis of the variation of the main aromatic metabolites present in Vanilla spp. pods from Costa Rica using high-performance liquid chromatography coupled with an ultraviolet detector (HPLC-UV)

The relationship between the physical characteristics of pods from four species of Vanilla spp. (V. planifolia, V. pompona, V. hardii, and the hybrid Costa Rica (HCR hybrid)), the cultivation region (Huetar Norte, Pacifico Central, and Brunca), and the processing state (green or cured) on the main aromatic metabolites present was evaluated, aiming to explore whether these factors can be associated with the quality of the final product. In the first stage, the physical appearance of the samples (dimensions, color, defects, etc.) was characterized and classified using a tool developed for this research. Moisture content was determined, and extracts were made in an ethanolic solution. The following metabolites were quantified by HPLC-UV (High-Performance Liquid Chromatography coupled with Ultraviolet detection): vanillin, p-hydroxybenzaldehyde, p-hydroxybenzoic acid, vanillic acid, anisic acid, p-hydroxybenzyl alcohol, anisic alcohol, vanillic alcohol, and guaiacol. The obtained data, once centered and standardized, were subjected to a Principal Component Analysis (PCA). Nine compounds were found that matched the retention time of the evaluated standards but not in the UV spectrum. Differences were also observed in the Principal Component Analysis (PCA) related to the processing state, but no clear differences concerning the cultivation regions. Samples from the Costa Rica hybrid, particularly those from the Central Pacific region, showed better overall quality, indicating great potential for commercial exploitation