Effect of Fermentation Methods and Turning Interval on the Quality of Cocoa Beans (Theobroma cacao)

Abstract

Cocoa (Theobroma cacao L.) is the main ingredient in the manufacture of chocolates and confectionery undergoes different unit operations, viz. fermentation, drying and roasting for a quality product. Fermentation followed by drying is an important farm level processing of cocoa. Fermentation studies were conducted by holding the cocoa beans (mixed F1 progeny varieties) in the bamboo basket, heaping on the floor and wooden box, and allowed to ferment for 6 days. During fermentation, the fermenting mass was manually turned at 12, 24 and 48h interval with a control. During the fermentation, pH of the pulp and beans, quantity of sweat collected temperature of the fermenting mass, moisture content of the mass and microbial population were determined following the standard procedures. After fermentation, the beans were dried by sun-drying, and the physical and biochemical qualities of dried cocoa beans, viz. bean count, number of beans per 100 g, bean texture, cut test, pH, titratable acidity and free fatty acid were determined. The method of fermentation and tuning intervals were non-significant on pH of pulp, moisture content, sweat produced, microbial population and free fatty acid. The method of fermentation and tuning intervals were significant on temperature profile, bean count, cut test and pH of bean. The microbial population varied with fermentation duration in all fermentation methods. In heap method with 48-h turning interval, pH, temperature and hardness (texture) were found higher than other fermentation methods. The per cent brown beans, considered as healthy beans, were at par with the turning interval and significant with the method of fermentation and were higher under the heap method at 12 and 24 h of turning intervals. Turning at 12h interval in heap method resulted in less acidic nature (titratable acidity) and desirable quality attributes, which is considered as optimum.