Under and fully fermented fine and bulk cocoa: A comparative study of volatile profile in different stages of...

The aroma profile and flavor of cocoa and chocolate is correlated with genotype, postharvest practices, and chocolate processing. To better understand the under-fermentation influence on the volatile compounds during bean-to-bar stages and to compare results with full fermentation, raw seeds, under-fermented and fully fermented cocoa beans, dried cocoa beans, cocoa nibs, and chocolate from bulk cocoa (Forastero and Pará), and fine cocoa (Scavina) were analyzed by solid-phase microextraction headspace gas chromatography-mass spectrometry (HS-SPME-CG-MS). Additionally, sensory acceptance test was conducted on under-fermented chocolates to verify consumer perception. A total of 131 volatile compounds were identified during processing. Under-fermentation contributed to the preservation and development of desirable volatile compounds, such as pyrazines, esters, and alcohols, especially after roasting and conching. Forastero cocoa had the highest number of volatiles (107), followed by Para (106) and Scavina (104), which exhibited high diversity and complexity of volatiles, reinforcing its classification as fine-flavored cocoa. In contrast, Forastero and Pará (bulk cocoa) showed a simpler and more intense profile. Despite differences in genotype and fermentation time, 26 key-aroma volatiles were common to all varieties, suggesting that under-fermentation can improve or maintain key-aroma markers with elevated total content (relative area percentage). Principal component analysis (PCA) and hierarchical cluster analysis (HCA heatmap) indicated distinct volatile groups associated with cocoa genotype and processing stage. Sensory evaluation revealed significant differences between under-fermented chocolate varieties. Pará achieved the highest acceptance scores for all attributes, followed by Scavina and Forastero. This study is one of the first to compare the fine-flavor Scavina with bulk cocoa through under-fermentation conditions. It sheds light on better understanding of how processing and genetics affect chocolate aroma characteristics and sensory acceptance.