Enhancing fermented cocoa bean quality and flavor through short secondary fermentation using Candida tropicalis as starter and Citrus limon peel

Secondary fermentation can reduce variability in cocoa bean quality caused by the spontaneous, uncontrolled nature of primary fermentation. However, its optimization remains unexplored. This study evaluated the improvement of secondary fermentation through the combined use of Citrus limon peel and inoculation with Candida tropicalis H1Y4-1 as a starter. Concentrations of 2%, 4%, and 6% (w/w) lemon components (dried slices and peel) and 10% (v/w) C. tropicalis were assessed in small-scale (250 g) and large-scale (2000 g) secondary fermentation. Optimal conditions - 4% (w/w) lemon peel, 10% (v/w) C. tropicalis, and a 30 min fermentation period - improved bean quality significantly. Well fermented beans increased from 60% to 85%, total phenolics rose by 38%, and levels of key amino acids increased, including phenylalanine (+14.29%), alanine (+10.21%), and aspartic acid (+11%). Sensory profiles also exhibited pronounced chocolate, fruity, and nutty notes. This rapid, cost-effective method has the potential to enhance the quality of fermented cocoa beans and create unique flavor profiles, benefiting the chocolate industry. © 2025 Society of Chemical Industry.