The influence of turning and environmental contamination on six spontaneous cocoa bean heap fermentations performed in Ghana was studied through a multiphasic approach, encompassing both microbiological (culture-dependent and culture-independent techniques) and metabolite target analyses. A sensory analysis of chocolate made from the fermented, dried beans was performed as well. Only four clusters were found among the isolates of acetic acid bacteria (AAB) identified: Acetobacter pasteurianus, Acetobacter ghanensis, Acetobacter senegalensis, and a potential new Acetobacter lovaniensis-like species. Two main clusters were identified among the lactic acid bacteria (LAB) isolated, namely, Lactobacillus plantarum and Lactobacillus fermentum. No differences in biodiversity of LAB and AAB were seen for fermentations carried out at the farm and factory sites, indicating the cocoa pod surfaces and not the general environment as the main inoculum for spontaneous cocoa bean heap fermentation. Turning of the heaps enhanced aeration and increased the relative population size of AAB and the production of acetic acid. This in turn gave a more sour taste to chocolate made from these beans. Bitterness was reduced through losses of polyphenols and alkaloids upon fermentation and cocoa bean processing.Raw cocoa beans have an astringent, unpleasant flavor and have to be fermented, dried, and roasted to obtain the desired characteristic cocoa flavor (27,30,41,45). Fermentation is hence the first step in cocoa powder and chocolate production. It is carried out spontaneously in heaps, boxes, baskets, or trays in cocoa-producing countries in the equatorial zone, led by the Ivory Coast, Brazil, and Ghana (1, 27). During the last decade, knowledge about the spontaneous cocoa bean fermentation process has been increasing (2,5,26,33,34,37). The microbiota involved in natural cocoa bean fermentation reflects the environmental factors (temperature, pH, and oxygen tension) and the metabolism of substrates of the cocoa bean pulp. This results in production times of significant amounts of ethanol, lactic acid, and acetic acid, representing a succession of yeasts, lactic acid bacteria (LAB), and acetic acid bacteria (AAB) during the cocoa bean fermentation course (2, 5, 36-38).In the last 5 years, the microbiology and biochemistry of Ghanaian cocoa bean heap fermentation processes have been studied in detail (5,18,26,33,34). During early and mid-time spontaneous fermentation of freshly harvested pulp and cocoa beans, piled into a heap, yeasts produce ethanol under anaerobic conditions and cause depectinization of the pulp, enabling the pulp to flow away and air ingress (37, 38). Concerning microaerophilic LAB, citrate-fermenting, acid-tolerant, and ethanol-tolerant Lactobacillus plantarum and Lactobacillus fermentum strains dominate the spontaneous cocoa bean fermentation process (5, 34). Citrate and sugars are converted into acetic acid, lactic acid, and mannitol, enabling a slight increase of the pH of the pulp (5). During the aerobic phase, ...