Cocoa bean fermentation

Fermentation is an important step in processing cocoa beans to make chocolate.

In fermentation, beans that have been removed from their pods are put together in close proximity. Yeasts, lactic acid bacteria and acetic acid bacteria break down pulp surrounding the beans and develop flavor precursors within the bean that create chocolate flavors during roasting. The process also reduces bitterness and gives beans a more brown hue.

Fermentation is divided between on-farm and centralized processing, with the former more common in West Africa and the latter more common in the Americas and parts of the Asia Pacific. In on-farm processing, which is how most fermentation has historically been undertaken, farmers wrap beans in leaves for around five days or move them between wooden boxes daily. In some countries such as Indonesia, cocoa beans undergo minimal fermentation and are sold as bulk filler.