Microbiological and Physicochemical Variations during Spontaneous Fermentation of Plantain Must.

Major losses are recorded every year in the plantain production sector in Côte d'Ivoire. These losses are mainly due to poor harvesting, transport, and storage conditions. Local processing of this food crop into other products could help limit postharvest losses. The aim of this study was to evaluate some microbiological and physicochemical parameters during the fermentation of plantain must for the production of an alcoholic beverage. Physicochemical parameters such as pH, titratable acidity, and reducing sugars were measured using a pH meter by titration and the Bernfeld method, respectively. Refractometric dry extract and alcohol content were measured using a refractometer. Loads of mesophilic aerobic germs, total coliforms, streptococci, and yeasts were determined by standard microbiological methods. Values for refractometric dry extract (10°B-4.5°B), reducing sugars (8.25-0 mg/mL), and pH (4.37-3.36) decrease during fermentation. The highest alcohol content (11%) is obtained after four days of fermentation of plantain must. In contrast to total coliforms (5.27-3.61 log10 cfu/mL), loads of mesophilic aerobic germs (4.84-9.8 log10 cfu/mL) increase during fermentation. Yeast and streptococci loads reach their peaks at 7.81 log10 cfu/mL and 8.15 log10 cfu/mL, respectively, after six (6) days of fermentation before dropping off. Plantain must could be used to produce distilled alcoholic beverages.

Microbiological and Physicochemical Characterization of Irrigation Water in Market Gardening in Korhogo.

Several sources of water are used by farmers without concern for quality, which can have consequences on the health of the consumer of market garden products. The aim of this study is to evaluate the microbiological and physicochemical qualities of irrigation water. Microorganisms were counted using the membrane filtration and incorporation into the agar methods. The physicochemical parameters were measured using multiparameter and spectrophotometric methods. The average values of the physicochemical parameters are between 6.46 and 6.9 (pH), 27.15 and 29.9°C (temperature), 170 and 760 µS/cm (electrical conductivity), 70 and 380 mg/L (total dissolved solids), 3.85 and 77.59 mg/L (nitrates), and between 0.13 and 2.35 mg/L for ammonium. Irrigation water in market gardening is highly contaminated by microorganisms. Loads ranging from 3.64 to 4.35 log10 cfu/100 mL, 2.44 to 3.31 log10 cfu/100 mL, 2.44 to 2.9 log10 cfu/100 mL, and 2.07 to 3.63 log10 cfu/100 mL were obtained for total coliforms, E. coli, fecal enterococci, and sulphite-reducing clostridia, respectively. Mean loadings ranging from 4.95 to 5.98 log10 cfu/100 mL, 1.8 to 2.08 log10 cfu/100 mL, and 1.5 to 1.98 log10 cfu/100 mL were obtained for mesophilic aerobic germs, moulds, and yeasts, respectively. Four different mould strains were identified in irrigation water. These strains belong to the genus Aspergillus. Shallows water was more contaminated with microorganisms. These results show that water should be treated before being used for irrigation; market garden products must be properly washed and disinfected before consumption.

Microbiological and Physicochemical Characteristics of Three Types of "Soumbara" from Seeds of African Locust Bean in Korhogo Markets, Côte d'Ivoire.

"Soumbara" is a fermented product sold in the markets of several West African countries. In the markets, it is sold in several formats (granulated, powder, and paste). The objective of this study was to evaluate the microbiological and physicochemical characteristics of these three types of "Soumbara" sold in the Korhogo markets. For this purpose, a preliminary survey followed by a sampling of 54 samples of "Soumbara" was carried out. The microorganism load count was carried out according to microbiological standards. The pH, titratable acidity, and moisture content were measured, respectively, with a pH meter, by dosing with sodium hydroxide solution and by differential weighing after passing the sample through the oven. The pH of the different samples is around 6. The moisture content is higher in "Soumbara" paste (20-24.7%) than in powdered (7.3-9.3%) and granulated (8.6-10.7%) "Soumbara." The acidity rates are between 0.07 and 0.13%, 0.2 and 0.3%, and 0.08 and 0.1%, respectively, for the granulated, powder, and paste types. Mesophilic aerobic germ loads (6.17-8.38 log10 cfu/g) for all three types of "Soumbara" are above the standard. Total coliform (1.13-2.96 log10 cfu/g), mould (0.86-2.52 log10 cfu/g), and yeast (0.33-1.53 log10 cfu/g) loads are below standard. The microbiological quality of the three types of "Soumbara" is unsatisfactory. Overall, "Soumbara" powder is the most contaminated, followed by granulated and paste "Soumbara." "Soumbara" must be added during culinary preparations in order to avoid possible public health problems.

Prevalence of Virulence Genes Associated with Diarrheagenic Pathotypes of Escherichia coli Isolates from Water, Sediment, Fish, and Crab in Aby Lagoon, Côte d'Ivoire.

This study was conducted to characterize virulence genes of Escherichia coli isolates from water, sediment, fish, and crab in Aby Lagoon. Serogrouping was performed by EPEC antisera in 113 E. coli strains. The presence of diarrhea-associated genes (eae, stx, AggR, elt, and est) was assessed by multiplex PCR using specific primers. Based on the multiplex PCR, sixty-two isolates (42 from water, 19 from sediment, and 1 from crab) were positive for virulence genes, including 34 positive for elt (ETEC), 46 positive for est (ETEC), 24 positive for both elt and est, 6 positive for stx (EHEC), 1 positive for both stx + est, and 1 positive for both stx + elt. Genes eae (EPEC) and AggR (EAEC) were not detected. Nine serogroups (O114, O127, O55, O111, O86, O119, O126, O128, and O142) were identified. This study revealed the presence of diarrheagenic and nondiarrheagenic E. coli and potential public health risks if fishery products are not appropriately cooked.