Lipidomic profile in cocoa (Theobroma cacao L.) beans with different clones and postharvest conditions

This study aimed to assess both fat content and fatty acid composition of the most common cocoa clones cultivated in Cameroon under the influence of different postharvest practices. The cocoa clones were selected from Mengang (3°53′ NL, 12°03′ EL), Center region of Cameroon and subjected to four postharvested conditions namely: fresh, fermented, unfermented dried and fermented dried cocoa beans. Physicochemical parameters (pH, cut-test, and fermentation index) of all samples were assessed. Total fat content was estimated by differentiating the nonfatty and fatty fractions. Gas chromatographic (GC-FID) analysis was applied to cocoa butter to determine lipid classes and fatty acids methyl esters (FAMEs). Stistical analysis (two-way ANOVA, HeatMap and ACP) were carried out. Total fat content was clone-dependent, ranging from 47 to 56 % of bean weight, and varied with postharvest practices. Lipidograms highlighted that cocoa butter accounts for over 97 % triacylglyrols. On the other hand, the descending order of fatty acids based on their fat content is stearic, oleic, palmitic and linoleic acids. This order is the same for all clones for fresh beans but changes depending on postharvest practice. The Lipid relative abundance and composition are correlated to each genotype. Statistical analysis shown that different cocoa in different postharvest practices can have the same fat content and a relatively similar composition. Therefore, the relative abundance of fats and their composition could be used to describe cocoa variety and posthavest stage.