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Abstract: To compare the spontaneous cocoa bean fermentation process carried out in different cocoa-producing regions, heap and box (one Ivorian farm) and box (two Brazilian farms) fermentations were carried out. All fermentations were studied through a multiphasic approach. In general, the temperature inside the fermenting mass increased throughout all fermentations and reached end-values of 42–48°C. The main end-products of pulp carbohydrate catabolism were ethanol, lactic acid, acetic acid, and/or mannitol. In the case of the fermentations on the selected Ivorian farm, the species diversity of lactic acid bacteria (LAB) and acetic acid bacteria (AAB) was restricted. Lactobacillus fermentum and Leuconostoc pseudomesenteroides were the predominant LAB species, due to their ethanol and acid tolerance and citrate consumption. The levels of mannitol, ascribed to growth of L. fermentum, were fermentation-dependent. Also, enterobacterial species, such as Erwinia soli and Pantoea sp., were among the predominating microbiota during the early stages of both heap and box fermentations in Ivory Coast, which could be responsible for gluconic acid production. Consumption of gluconic acid at the initial phases of the Ivorian fermentations could be due to yeast growth. A wider microbial species diversity throughout the fermentation process was seen in the case of the box fermentations on the selected Brazilian farms, which differed, amongst other factors, regarding pod/bean selection on these farms as compared to fermentations on the selected Ivorian farm. This microbiota included Lactobacillus plantarum, Lactobacillus durianis, L. fermentum, Lactobacillus mali, Lactobacillus nagelii, L. pseudomesenteroides, and Pediococcus acidilactici, as well as Bacillus subtilis that was present at late fermentation, when the temperature inside the fermenting mass reached values higher than 50°C. Moreover, AAB seemed to dominate the Brazilian box fermentations studied, explaining higher acetic acid concentrations in the pulp and the beans. To conclude, it turned out that the species diversity and community dynamics, influenced by local operational practices, in particular pod/bean selection, impact the quality of fermented cocoa beans. [Copyright &y& Elsevier]

Abstract: Metabolite production due to bacterial outgrowth and oxidation phenomena lead to spoilage development of cooked ham. Artisan-type products, with low salt concentrations and a minimum of additives, are particularly sensitive. Cold chain variations related to distribution and consumer habits have a negative influence on the shelf-life. In this study, sliced, modified atmosphere packaged artisan-type cooked ham was stored at different temperatures (4, 7, 12, and 26°C). The evolution of volatiles over time for the different storage temperatures was monitored with static headspace gas chromatography/mass spectrometry (SH–GC–MS). The latter method was compared to solid phase microextraction (SPME). Several of the detected compounds could be ascribed to bacterial glucose and amino acid metabolism and their production was related to the storage temperature. The compounds 3-methyl butanol and ethanol were related with bacterial cell growth. Maillard-derived compounds, leading to the formation of furans, probably originated from endogenous reactions during cooking. Several detected aliphatic compounds probably originated from fatty acid oxidation reactions, including thermal fat degradation, chemical auto-oxidation, and enzymatic β-oxidation. [Copyright &y& Elsevier]