title: Influence of turning and environmental contamination on the dynamics of populations of lactic acid and acetic acid bacteria involved in spontaneous cocoa bean heap fermentation in Ghana.
abstract: 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.
authors.affiliation: Research Group of Industrial Microbiology and Food Biotechnology, Department of Applied Biological Sciences and Engineering, Vrije Universiteit Brussel, Pleinlaan 2, B-1050 Brussels, Belgium.
authors.forename: Nicholas
authors.initials: N
authors.lastname: Camu
authors.forename: Angel
authors.initials: A
authors.lastname: González
authors.forename: Tom
authors.initials: T
authors.lastname: De Winter
authors.forename: Ann
authors.initials: A
authors.lastname: Van Schoor
authors.forename: Katrien
authors.initials: K
authors.lastname: De Bruyne
authors.forename: Peter
authors.initials: P
authors.lastname: Vandamme
authors.forename: Jemmy S
authors.initials: JS
authors.lastname: Takrama
authors.forename: Solomon K
authors.initials: SK
authors.lastname: Addo
authors.forename: Luc
authors.initials: L
authors.lastname: De Vuyst
mesh_terms: D019342:Acetic Acid / Q000378:metabolism; D000091:Acetobacter / Q000145:classification / Q000235:genetics / Q000302:isolation & purification* / Q000378:metabolism; D044822:Biodiversity; D002099:Cacao / Q000737:chemistry / Q000378:metabolism / Q000382:microbiology*; D016000:Cluster Analysis; D016172:DNA Fingerprinting; D004269:DNA, Bacterial / Q000235:genetics; D005285:Fermentation; D005869:Ghana; D019344:Lactic Acid / Q000378:metabolism; D052197:Limosilactobacillus fermentum / Q000145:classification / Q000235:genetics / Q000302:isolation & purification* / Q000378:metabolism; D048191:Lactiplantibacillus plantarum / Q000145:classification / Q000235:genetics / Q000302:isolation & purification* / Q000378:metabolism; D013649:Taste
chemical_list: D004269:DNA, Bacterial; D019344:Lactic Acid; D019342:Acetic Acid