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Seeds of Parkia biglobosa, also called African locust bean seeds (ALBSs), are used to produce a condiment by subjecting them to cooking, alkaline fermentation, and drying. The objective of this work was to monitor the evolution of the composition of ALBS during spontaneous fermentation. Results showed that the seeds at initial time contained mainly proteins (45%) and lipids (36%). During fermentation, the conversion of this initial composition took place to produce ammonium, free amino acids, and short‐chain fatty acids (SCFAs) that accounted for 2%, 10%, and 1.5% dry basis, respectively, which explains the typical flavor of fermented ALBS. This release was also concomitant with biogenic amine production. Along with ammonium and SCFA release, pyrazines were the major volatile organic compounds. Composition modulation was well represented by a Verhulst equation in which the dynamic could be modified by the initial composition of the seed, the pre‐cooking step, and the fermentation conditions (temperature and aeration). Practical applications: For nutritional and sustainability reasons, re‐integration of vegetable in general and legumes, in particular in our diet, is a current trend. However, only dish that are appealing to consumers are concretely adopted. Fermentation of legumes is interesting in more than one way. It does not involve heat, so thermolabile molecules can be preserved and the financial and energetic costs are low. Biological interesting molecules are produced from the metabolism of microorganisms, and among them, volatile organic compounds that contribute to enhance the flavor of legume dishes. Soumbala is a meal and/or condiment obtained from the fermentation of African locust bean (Parkia biglobosa) seeds (ALBSs), a legume widely spread in west Africa. The final typical sensory properties are known to be due to the alkaline fermentation step by Bacillus species. This paper presents the kinetics of release of various compounds during spontaneous fermentation that may impact the sensory and nutritional properties of the final product. More precisely, the dynamic of the production of free amino acids, free fatty acids, volatile compounds, and biogenic amines are presented and discussed to give insights into the succession of important reactions to control the sensory and nutritional qualities of fermented ALBS (FALBS). This paper shows that further research are necessary to better understand and control the quality of not only FALBS but also similar protein‐rich legumes to modulate the quality of the final products. [ABSTRACT FROM AUTHOR]

Acetic acid bacteria are involved in many food and beverage fermentation processes. They play an important role in cocoa bean fermentation through their acetic acid production. They initiate the development of some of the flavor precursors that are necessary for the organoleptic quality of cocoa, and for the beans' color. The development of starter cultures with local strains would enable the preservation of the microbial biodiversity of each country in cocoa-producing areas, and would also control the fermentation. This approach could avoid the standardization of cocoa bean fermentation in the producing countries. One hundred and thirty acetic acid bacteria were isolated from three different cocoa-producing countries, and were identified based on their 16S rRNA gene sequence. The predominate strains were grown in a cocoa pulp simulation medium (CPSMAAB) in order to compare their physiological traits regarding their specific growth rate, ethanol and lactic acid consumption, acetic acid production, and relative preferences of carbon sources. Finally, the intraspecific diversity of the strains was then assessed through the analysis of their genomic polymorphism by (GTG)5-PCR fingerprinting. Our results showed that Acetobacter pasteurianus was the most recovered species in all of the origins, with 86 isolates out of 130 cultures. A great similarity was observed between the strains according to their physiological characterization and genomic polymorphisms. However, the multi-parametric clustering results in the different groups highlighted some differences in their basic metabolism, such as their efficiency in converting carbon substrates to acetate, and their relative affinity to lactic acid and ethanol. The A. pasteurianus strains showed different behaviors regarding their ability to oxidize ethanol and lactic acid into acetic acid, and in their relative preference for each substrate. The impact of these behaviors on the cocoa quality should be investigated, and should be considered as a criterion for the selection of acetic acid bacteria starters. [ABSTRACT FROM AUTHOR]

Ablo is a rice or maize-based steam-cooked bread-like product, very popular in Benin, Togo and Ghana. This study optimized the processing steps of rice ablo using response surface methodology. The effect of precooking (proportions of flour and water, duration), kneading (wheat level, duration), fermentation (yeast level, temperature, duration) conditions to dough (gelatinization level, fluidity, proofing) and ablo (ethanol content, pH, density, cooking expansion, firmness, alveolar structure) properties were studied. It was demonstrated that ablo texture can be controlled by the fluidity of the fermented dough. Fluid fermented dough (at least 0.5 cm/s) expands adequately during steam-cooking and results in a less dense ablo in line with commonly consumed ablo. The optimal dough fluidity comes from a low gelatinization level of the precooked dough (less than 20%) and an intense fermentation (high yeast dose and long fermentation). Surprisingly, dough proofing appears to have no effect on final ablo expansion. [ABSTRACT FROM AUTHOR]