Fungi and mycotoxins in cocoa: From farm to chocolate

Abstract

Cocoa is an important crop, as it is the rawmaterial fromwhich chocolate ismanufactured. It is grownmainly in West Africa although significant quantities also come fromAsia and Central and South America. Primary processing is carried out on the farm, and the flavour of chocolate starts to develop at that time. Freshly harvested pods are opened, the beans, piled in heaps orwooden boxes, are fermented naturally by yeasts and bacteria, then dried in the sun on wooden platforms or sometimes on cement or on the ground, where a gradual reduction in moisture content inhibits microbial growth. Beans are then bagged and marketed. In processing plants, the dried fermented beans are roasted, shelled and ground, then two distinct processes are used, to produce powdered cocoa or chocolate. Filamentous fungi may contaminate many stages in cocoa processing, and poor practices may have a strong influence on the quality of the beans. Apart from causing spoilage, filamentous fungi may also produce aflatoxins and ochratoxin A. This review deals with the growth of fungal species and formation of mycotoxins during the various steps in cocoa processing, aswell as reduction of these contaminants by good processing practices.Methodologies for fungal and mycotoxin detection and quantification are discussed while current data about dietary exposure and regulation are also presented. © 2014 Elsevier B.V. All rights reserved.