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The high phenolic content of Palm Oil Mill Effluent (POME) constitutes an environmental concern. In this study, laccase producing microorganisms were isolated from POME samples collected in Cote d’Ivoire for their possible use in POME treatment. Strain showing the highest laccase activity was identified by ITS1-5.8S-ITS2 region sequencing as Trametes polyzona. A maximum laccase production (156.3 U/mL) was obtained after 10 days of incubation under shaking condition, at 37 °C, pH 4, with starch (1%), tryptone (0.3%) and 10 mM of guaiacol. The partially purified laccase of 31 kDa exhibited maximum activity at 50 °C and pH 4.5 with a Km for guaiacol and Vmax of 0.7 mM and 0.04 mM/min, respectively. Metals, SDS and EDTA did not inhibit his activity. Used as biotreatment agent, T. polyzona MPS1-3 reduced COD, total suspended solids, total solids and total phenolics by 16.03%, 70.15%, 38.9%, 50.84%, respectively, for sterilized POME and by 13.09%, 58.07%, 36.53%, 42.05% for unsterilized POME. These results showed the promising application of T. polyzona for bioremediation of phenolics compounds in wastewater and it potentially useful in several other biotechnological applications.

Palm wine, the most commonly consumed traditional alcoholic beverage in Western Africa, harbours a complex microbiota and metabolites, which plays a crucial role in the overall quality and value of the product. In the present study, a combined metagenomic and metabolomic approach was applied to describe the microbial community structure and metabolites profile of fermented saps from three palm species (Elaeis guineensis, Raphia hookeri, Borassus aethiopum) in Côte d’Ivoire. Lactobacillaceae (47%), Leuconostocaceae (16%) and Acetobacteriaceae (28%) were the most abundant bacteria and Saccharomyces cerevisiae (87%) the predominant yeasts in these beverages. The microbial community structure of Raphia wine was distinctly different from the others. Multivariate analysis based on the metabolites profile clearly separated the three palm wine types. The main differentiating metabolites were putatively identified as gevotroline hydrochloride, sesartemin and methylisocitrate in Elaeis wine; derivative of homoserine, mitoxantrone in Raphia wine; pyrimidine nucleotide sugars (UDP-D-galacturonate) and myo-Inositol derivatives in Borassus wine. The enriched presence of gevotroline (an antipsychotic agent) and mitoxantrone (an anticancer drug) in palm wine supports its therapeutic potential. This work provides a valuable insight into the microbiology and biochemistry of palm wines and a rationale for selecting functional microorganisms for potential biotechnology applications.

Palm Oil Mill Effluents (POME) are complex fermentative substrates which habour diverse native microbial contaminants. However, knowledge on the microbiota community shift caused by the anthropogenic effects of POME in the environment is up to date still to be extensively documented. In this study, the bacterial and archaeal communities of POME from two palm oil processing systems (artisanal and industrial) were investigated by Illumina MiSeq Platform. Despite the common characteristics of these wastewaters, we found that their microbial communities were significantly different with regard to their diversity and relative abundance of their different Amplicon Sequence Variants (ASV). Indeed, POME from industrial plants harboured as dominant phyla Firmicutes (46.24%), Bacteroidetes (34.19%), Proteobacteria (15.11%), with the particular presence of Spirochaetes, verrucomicrobia and Synergistetes, while those from artisanal production were colonized by Firmicutes (92.06%), Proteobacteria (4.21%) and Actinobacteria (2.09%). Furthermore, 43 AVSs of archaea were detected only in POME from industrial plants and assigned to Crenarchaeota, Diapherotrites, Euryarchaeota and Nanoarchaeaeota phyla, populated mainly by many methane-forming archaea. Definitively, the microbial community composition of POME from both type of processing was markedly different, showing that the history of these ecosystems and various processing conditions have a great impact on each microbial community structure and diversity. By improving knowledge about this microbiome, the results also provide insight into the potential microbial contaminants of soils and rivers receiving these wastewaters.

In order to phenotypically characterized Saccharomyces cerevisiae strains isolated from sorghum beer and palm wines for a possible selection of a starter culture, 30 strains were tested for killer activity, temperature resistance, ethanol tolerance, carbohydrate fermentation, enzyme profile and sorghum wort fermentation. Of the tested strains, three showed a killer profile, while four showed a neutral profile and 23 were found to be sensitive to K2 toxin. Temperatures of 40 °C and 44 °C allowed to distinguish strains into four thermal groups with only three strains may grow at 44 °C. Almost tested strains were tolerant to 5% ethanol with viability rates up to 73%. But at 10% and 15% ethanol, respectively 18 and 7 strains were tolerant. Carbohydrate fermentation revealed 13 fermentation profiles, including one typical and 12 atypical profiles. The typical profile strains (16.13% of the strains) fermented glucose, galactose, fructose, sucrose, maltose, trehalose and raffinose. Most of the strains secreted lipases (mainly esterase and esterase-lipase), proteases (mainly valine and cysteine arylamidase, chrymotrypsin) and phosphatases (mainly acid phosphatase and naphthol phosphohydrolase). On contrary, only five strains isolated from sorghum beer exhibited glucosidase activity, mainly α-glucosidase. The analyse of fermented sorghum wort revealed that fermentative performance is strain dependent. Furthermore, the Hierarchical Cluster Analysis showed that the strains were separated in three distinct clusters with the strains from sorghum beer clustered separately.

The study was carried out to analyse volatile compounds (VOCs) associated to sensory changes during the storage of traditional sorghum beer at ambient temperature and 4 °C. Tchapalo samples were collected and stored at ambient temperature (27–30 °C) for four days and at 4 °C for six days. Volatile and sensory changes were monitored during the storage period. VOCs were extracted and detected using HS-GC/FID and SPME-GC/MS. These methods allowed to identify 68 volatile compounds. The use of SPME fiber permitted to obtain 63 volatile compounds, while simple headspace (HS) was able to extract only 10 compounds. The proportions of isoamyl alcohol, phenylethyl alcohol, ethyl lactate, isoamyl acetate, ethyl hexanoate, ethyl DL-leucate, ethanol, diethyl succinate, phenethyl acetate and benzene acetaldehyde observed significant variation during the storage at ambient temperature. For Tchapalo stored at 4 °C, the proportions of ethanol, ethyl lactate, isoamyl acetate, ethyl hexanoate, ethyl octanoate and phenylethyl alcohol presented significant variation. Principal component analysis based on quantitative changes of these volatile compounds showed three groups among Tchapalo samples which reflected to the differences observed during the sensory evaluations.

This study identified biogenic amines, fatty acids, and volatile compounds in adjuevan, an Ivorian traditionally salted and fermented fish. Samples were obtained from two processing methods (method 1: entire fish adjuevan; method 2: both sides filleted adjuevan) with the fish species Galeoides decadactylus. Biogenic amines found in freshly produced adjuevanwere histamine, putrescine, cadaverine, tyramine, -phenyl ethylamine, and spermidine. Among these, the most prevalent were -phenyl ethylamine and cadaverine. Biogenic amine contents varied according to the processing method but re-mained lower than levels considered hazardous for human health. The major fatty acids present in adjuevan from method 1 were docosahexaenoic acid, palmitic acid, and oleic acid. In adjuevan from method 2, the major fatty acids were oleic acid, stearic acid, and palmitic acid. The omega ()-3/-6 ratio was 8.87 and 4.12 for adjuevan from methods 1 and 2, respec-tively. Most of the fatty acids are considered healthy fats, making adjuevan a useful food for treating and preventing life-style diseases. The volatile compounds found composed of 19 aldehydes, 12 alcohols, 7 esters, 7 ketones, 3 furans, 10 aro-matic compounds, and 7 acids with aldehyde, alcohol, and ester compounds as the predominant groups. Among the alde-hydes, 2,4-heptadienal (E,Z), octanal, and 2-octenal (E) were most prevalent in adjuevan from method 1, whereas 2-none-nal (E), 2,4-heptadienal (E,Z), and octanal were most prevalent in adjuevan from method 2.

To document and speed up research on the usefulness and selection of potential health-promoting bacterial starter cultures from unexplored fermented saps of various palm species in Cote d'Ivoire, benchmark tapping processes were successfully developed and implemented at field level. Therefore, spontaneously fermented saps of three palm species (Elaeis guineensis, Raphia hookeri, Borassus aethiopum) were collected throughout tapping process and lactic acid bacteria (LAB) diversity and dynamics were studied through a multiphasic approach. Overall microbiological analysis revealed a LAB species diversity throughout tapping process. LAB isolates belonged to two main (GTG)5-PCR clusters, namely Fructobacillus durionis (40.33%) and Leuconostoc mesenteroides (45.66%), with Leuconostoc pseudomesenteroides, Lactobacillus paracasei, Lactobacillus fermentum Weissella cibaria, Enterococcus casseliflavus and Lactococcus lactis occurring occasionally. LAB diversity was higher in fermented saps from E. guineensis (8 species) than those of R. hookeri (5 species) and B. aethiopum (3 species). Dynamic study revealed that F. durionis and L. mesenteroides dominated the fermentations from the beginning until the end of tapping process in all palm wine types. But the earlier stages of the process were also populated by some species like W. cibaria, L. pseudomesenteroides and L. fermentum, which population decreased or disappeared after some days. Also, species of Enterococcus and Lactococcus genera were sporadically detected uniquely in sap from E. guineensis. This study is the first to investigate extensively the LAB diversity and dynamics throughout palm trees tapping process in Cote d'Ivoire and is relevant for future selection of health promoting bacteria.

Production of attieke in Cote d'Ivoire requires the use of inputs such as the cassava traditional inocula, palm oil and water. These three inputs are involved in the entire production process. Contamination of these ingredients will result in a finished product of uncertain health quality. For the implementation of HACCP (Hazard Analysis Critical control Point) in the production of attieke in Cote d'Ivoire, it is therefore necessary to identify the microbiological hazards in these ingredients (cassava traditional inocula, palm oil and the water used for the production of attieke). The imputs contained pathogenic microorganisms. Bacillus subtilis, Bacillus cereus, Staphylococcus aureus, Citrobacter freundi, Enterobacter amnigenus, Citrobacter youngae, Enterobacter aerogenes, Klebsiella pneumoniae, Enterobacter agglomerans and Klebsiella oxytoca were the bacteria isolated, and Rhizopus spp., Mucor spp., Thamnidium spp., Fusarium spp., Moniliella spp. were the fungi isolated.The occurrence of some bacteria and fungi illustrate that cassava traditional inocula, water and palm oil used in attieke proccess collected in Côte d’Ivoire may act as a reservoir of potential pathogenic micro-organisms for human.The finished product which is the attieke must undergo a particular treatment in order to ensure its microbiological quality.

Despite the increasing importance of palm wines as a key element in Ivorian socio-cultural practices, and the high involment of yeasts in the production of these beverages, no studies have been devoted to aroma production of yeasts and their potential uses in biotechnological applications. In this work, aroma profiles of 20 non pathogenic yeast strains (11 from raffia and 9 from ron, representing 13 species) among the 21 yeasts isolated were established using HS–SPME–GC/MS analysis. A total of 50 Volatile Organic Compounds (VOCs) produced by these yeasts were identified and grouped into five main families, namely higher alcohols, aldehydes, ketones, organic acids and esters. Among these VOCs, esters were the most abundant (28 compounds). Some strains produced specific compounds of technological interest which could be used for diverse applications, such as beverages, ice creams, baked goods and desserts and synthetic flavouring ingredient. Among them, Hanseniaspora jakobsenii CLIB 3083 produced the highest number of VOCs.

In order to assess the genetic diversity and population structure of indigenous S. cerevisiae from Côte d'Ivoire, a total of 170 strains were isolated from four traditional alcoholic beverages through nine regions. Microsatellite analysis performed at 12 loci revealed that strains of palm oil and raffia wine were genetically related, unlike those of tchapalo and ron wine which formed two s from palm oil wine and raffia wine were clearly inbred. In comparison with the European, North American, Asian and others West African populations, Ivorian population was well defined, although most of these strains were admixed. Among these strains, only isolates from raffia wine appeared to have alleles in common to all populations.

Yeasts, lactic and acetic acid bacteria are responsible of microbial spoilage of alcoholic beverages. However species involved in deterioration of sorghum beer produced in Cote d’Ivoire has not been investigated. This study was carried out to identify species of yeast, LAB and AAB during spoilage of tchapalo in order to define the best strategy for beer preservative. Thus, a total of 210 yeasts, LAB and AAB were isolated from samples of tchapalo stored at ambient temperature and at 4 °C for 3 days. Based on PCR–RFLP of the ITS region and the sequencing of D1/D2 domain, yeast isolates were assigned to seven species (Saccharomyces cerevisiae, Candida tropicalis, Rhodotorula mucilaginosa, Trichosporon asahii, Kluyveromyces marxianus, Meyerozyma guilliermondii and Trichosporon coremiiforme). During the storage at ambient temperature and at 4 °C, S. cerevisiae was the predominant species (> 76%). Excepted R. mucilaginosa, occurrence of non-Saccharomyces species was sporadic. LAB species detected in fresh samples using molecular methods were Pediococcus acidilactici, Lactobacillus paracasei, Lb. curvatus, Lb. fermentum and Weisssella paramesenteroides. P. acidilactici was the dominant species (47.8%) followed by Lb. paracasei (17.5%). W. paramesenteroides and Lb. fermentum were not detected during the spoilage at ambient temperature while at 4 °C W. paramesenteroides and Lb. paracasei have not been detected. For AAB, the species found were Acetobacter pasteurianus sub paradoxus and Acetobacter cerevisiae. These species were common to all samples during spoilage and A. pasteurianus sub paradoxus was the most frequently detected.

In order to extend shelf life of traditional sorghum beers, it is of importance to evaluate their spoilage characteristics. Therefore, the microbiological, biochemical, and sensory changes of the Ivorian sorghum beer tchapalo during storage at ambient temperature (28 to 30 °C) for four days and at 4 °C for six days were assessed. The aerobic mesophilic bacteria and the yeast counts remained stable during the storage time. However, variations were observed in the lactic acid bacteria and acetic acid bacteria counts. The deteriorating tchapalo acidity did not show significant variations. In contrast, the total soluble solids decreased at ambient temperature and remained stable at 4 °C. Lactic acid was a major compound during storage, and acetic acid was found at a detectable level of 1.26 mg/mL after the third day at ambient temperature. The ethanol contents increased significantly at ambient temperature after two days and then decreased but showed a fair decrease at 4 °C. Evaluating the beer’s appearance, odor, and taste, a panel considered the beers to be spoiled after two days when stored at 28 to 30 °C and after three days when stored at 4 °C.

The aims of this study were to investigate the food safety knowledge and practices of food handlers and to assess the sanitary conditions of attieke production units in the South of C?te d’Ivoire. A cross-sectional study was conducted during 4 months in 2012 in 7 localities and data were collected using questionnaire and observation checklist and microbiological analysis of hands. A total of 775 attieke production units were involved in this survey. Seventy-one percent (71%) were located on public domains and only 70 production units (9%) used septic tank as a mean of final deposal for liquid waste. Hygiene conditions and practices of food handlers in attieke production units were inadequate. The presence of specific microorganisms such as Staphylococcus aureus, Klebsiella pneumoniae, Enterobacter agglomerans, Citrobacter youngae, Klebsiella oxytoca and Citrobacter freundi was indicative of a degree of ignorance on the part of food handlers towards proper hygienic practices.

Two lactic acid bacteria strains (At1BEAE22 and At344E21) isolated during tchapalo production were identified on the basis of phenotypic analyses. Bacteriocins produced by these strains were tested for their antimicrobial activities using well diffusion agar method. Heat resistance, pH sensitivity and enzyme treatments were also analyzed. Results showed that both lactic acid bacteria strains were identified as Pediococcus acidilactici. Their bacteriocins inhibited growth of Lactobacillus delbrueckii F/31, Listeria innocua ATCC 33090, Enterococcus faecalis, Enterococcus faecalis ATCC 29212, Streptococcus sp, Enterococcus faecalis CIP 105042 and Enterococcus faecium ATCC 51558. These bacteriocins were heat stable at 60&degC for 30 min for all indicator bacteria. However, they remained active only against Lactobacillus delbrueckii and Listeria innocua at 121&degC for 60 min. Moreover, they were active in a wide range of pH (3 to 9) with a maximum activity observed at pH 5 and 6 on all indicator bacteria. But, bacteriocin from Pediococcus acidilactici At34E21 was more stable at acidic pH than basic one. The fact that the bacteriocin was inactivated by proteinase K and α-chymotrypsin indicated its proteinaceous nature, a general characteristics of bacteriocins.

Objectif: Cette etude vise a degager l’originalite de la fermentation lactique au cours de la production de l’ attieke (semoule de manioc cuite a la vapeur) dans les espaces ethnoculturels Adjoukrou , Ahizi et Ebrie . Methodologie et Resultats: Une caracterisation des ferments a ete realisee a travers la composition en bacteries lactiques (charge, type morphologique et especes de bacteries lactiques) des ferments traditionnels de manioc Adjoukrou, Ahizi et Ebrie . Il ressort de cette analyse preliminaire que la population des bacteries lactiques des ferments Ahizi est composee de 58,34 % de coccobacilles, 25 % de bacilles et 16,66 % de cocci. Dans les ferments Ebrie , les cocci et les bacilles sont deceles dans des proportions respectives de 58,34 % et 41,66 %. Les ferments Adjoukrou et Ahizi sont domines par une espece du genre Weissella et le ferment Ebrie par une espece de Leuconostoc . En ce qui concerne la dynamique des bacteries lactiques au cours de la fermentation de la pâte de manioc, pour la production de l’ attieke Adjoukrou , sur les trois sites de Debrimou, les fermentations sont initiees et conduites par des CCG+(Coccobacilles Gram+) representees par quatre especes de Weissella . Par contre, la fermentation de la pâte de manioc de type Ahizi presentait deux phases. La premiere phase est marquee par la croissance des bacteries BG+ (Bacilles Gram+) ( Lactobacillus plantarum et lactobacillus fermentum ). La deuxieme est dominee par la croissance des Enterococcus italicus . Quant a la production de l’ attieke Ebrie est initiee et conduite par des CCG+ (Coccobacilles Gram+) representes par des especes de Weissella . Ce n’est qu’apres huit heures de fermentation que la croissance des CG+ (Cocci Gram +) ( Leuconostoc mesenteroides et Leuconostoc subsp mesenteroides ) est plus activee. Conclusion et principales applications de la recherche: Cette etude a permis de degager les specificites de la fermentation lactique pour chacune des zones d’etude. Ces ferments serviront de bases de donnees pour la mise en place d’un starter typique a chaque type d’ attieke en Cote d’Ivoire. Mots Cles: Fermentation, Dynamique, Bacterie lactiques, Attieke English Abstract Objective: This study aims to identify the originality of lactic fermentation during the production of Attieke (steamed cassava fermented semolina) in the spaces ethnocultural Adjoukrou , Ahizi and Ebrie. Methodology and Results: A characterization of the ferments was carried out through the lactic acid bacteria composition (load, morphological type and species of lactic acid bacteria) of the traditional cassava ferments Adjoukrou , Ahizi and Ebrie . This preliminary analysis showed that the lactic bacteria population of Ahizi ferments was composed of 58.34% coccobacilli, 25% bacilli and 16.66% cocci. In the Ebrie ferments, cocci and bacilli were detected in respective proportions of 58.34% and 41.66%. Adjoukrou and Ahizi ferments were dominated by a species of the genus Weissella and Ebrie ferment by a species of Leuconostoc . With regard to the dynamics of lactic acid bacteria during the fermentation of cassava dough, for the production of Adjoukrou attieke , at the three Debrimou sites, fermentations were initiated and conducted by GCC+ (Coccobacillus Gram+) represented by four species of Weissella . On the other hand, the fermentation of the Ahizi cassava dough evolved in two phases. The first phase was marked by the growth of BG + (bacilli Gram +) bacteria ( Lactobacillus plantarum and Lactobacillus fermentum ). The second was dominated by the growth of Enterococcus italicus . For the production of Attieke Ebrie the cassava dough fermentation was initiated and conducted by CCG+ ( Coccobacillus Gram +) represented by Weissella species. But only after eight hours of fermentation that the growth of CG + (Cocci Gram +) ( Leuconostoc mesenteroides and Leuconostoc subsp. Mesenteroides ) was activated the most. Conclusion and main applications of research : This study made it possible to identify the specificities of lactic fermentation for each of the study areas. These ferments will serve as databases for the establishment of a starter typical of each type of attieke in Cote d'Ivoire. Keywords: Fermentation, Dynamics, Lactic Bacteria, Attieke

Starter cultures of Candida tropicalis and Saccharomyces cerevisiae isolated from tchapalo were tested in pure culture and co-culture of four ratios [2:1, 25:4, 1:4, 2:3 (cells/cells)] for their ability to ferment sorghum wort to produce tchapalo. All the starters showed means growth rate between 0.043 and 0.101 h−1. Only C. tropicalis in pure culture showed growth rate lower than that of S. cerevisiae in single culture. During fermentation, according to total soluble solids depletion, yeast starters could be grouped in four different profiles. But in the beer produced, total soluble solids contents were statistically identical. The lowest values were obtained with co-culture C. tropicalis + S. cerevisiae in the ratios of 2:1 and 2:3. Starter cultures with large ratio of C. tropicalis produced a higher organic acids and 2-butanone than S. cerevisiae in pure culture. However, co-culture C. tropicalis + S. cerevisiae (2:1) was the alone starter which produced higher ethanol than S. cerevisiae in pure culture. The beers produced with C. tropicalis + S. cerevisiae (25:4), C. tropicalis + S. cerevisiae (1:4) and C. tropicalis were widely different from those produced with the others starter cultures.

Raffia wine is a traditional alcoholic beverage produced in several African countries where it plays a significant role in traditional customs and population diet. Alcoholic fermentation of this beverage is ensured by a complex natural yeast flora which plays a decisive role in the quality of the final product. This present study aims to evaluate the distribution and the diversity of the yeast strains isolated in raffia wine from four sampling areas (Abengourou, Alépé, Grand-Lahou and Adzopé) in Côte d'Ivoire. Based on the D1/D2 domain of the LSU rDNA sequence analysis, nine species belonging to six genera were distinguished. With a percentage of 69.5 % out of 171 yeast isolates, Saccharomyces cerevisiae was the predominant species in the raffia wine, followed by Kodamaea ohmeri (20.4 %). The other species isolated were Candida haemulonii (4.1 %), Candida phangngensis (1.8 %), Pichia kudriavzevii (1.2 %), Hanseniaspora jakobsenii (1.2 %), Candida silvae (0.6 %), Hanseniaspora guilliermondii (0.6 %) and Meyerozyma caribbica (0.6 %). The molecular characterization of S. cerevisiae isolates at the strain level using the PCR-interdelta method revealed the presence of 21 profiles (named I to XXI) within 115 isolates. Only four profiles (I, III, V and XI) were shared by the four areas under study. Phenotypic characterization of K. ohmeri strains showed two subgroups for sugar fermentation and no diversity for the nitrogen compound assimilations and the growth at different temperatures.

Mitragyna ciliata (Aubrev and Pellegr) (Rubiaceae) is a plant commonly used in traditional medicine in Cote d'Ivoire for the malaria treatment. This plant's extract was obtained by maceration of the powdered leaves in methanol. It was evaluated for its intrinsic antiplasmodial activity, its ability to synergise in vitro the effect of chloroquine against drug-resistant Plasmodium falciparum FcM29 strain using isobologram analysis. The cytotoxic activity was estimated on HeLa cells and the ratio of cytotoxicity/antimalarial activity calculated. As results; the IC 50 values for the antiplasmodial activity were ranged from 14 to 44 μg/ml depending on incubation duration, strains or isolates tested. The extract showed the reversal of chloroquine resistance in FcM29 strain. The mean cytotoxicity/antiplasmodial for this extract was determinated at 13.

Diversity of yeasts was investigated by using a molecular technique employing variable regions of 26S rDNA profiles generated by PCR-denaturing gradient gel electrophoresis (DGGE) in the salted and fermented traditional fish named "adjuevan". This fermented fish was produced in Ivory Coast at ambient temperature (28 to 30°C) following two traditional fermentation methods. Fermentation according to Method 1 was made in jars covered with plastics and stones for 5 days then dried for three days on racks or nets. For Method 2, fermentation and fish drying took place on racks or nets simultaneously for at least 10 days. PCR-DGGE and DNA sequencing was used to compare yeasts from both methods of production, and they were identified as Kluyveromyces marxianus, Hansenula anomala, Saccharomyces cerevisiae, Candida tropicalis, Candida zeylanoides, Pichia fermentans, Debaromyces hansenii, Hanseniaspora osmophilic, and Rhodotorula glutinis which had not been previously described in fermented fish. Yeast diversity was higher for Method 1, while the predominance strains of Debaromyces sp. and Candida sp. with Kluyveromyces sp. were higher for Method 2. This study showed the presence of yeast species and their participation in the fermentation of adjuevan. D. Hansenii and K. marxianus could be used as starter cultures for the standardisation of the fermented fish, adjuevan. (Resume d'auteur)

The production of tchapalo remains more or less an empirical process. For the improvement of the product quality, there is a need of more knowledge on this traditional process and the beer characteristics. The alcoholic fermentation is one of the most steps which most determines the quality of the beer. In this study, the characteristics of the traditional starter and the evolution of temperature, ethanol, sugars and organic acids were assessed at small-scale production during alcoholic fermentation of tchapalo. Brewers used traditional starter at the rate of 0.76-0.88 % when it was dried or at 2.38 % when it was not. When the wort was at 36.6-39.3 °C, the starter was added to initiate the fermentation. Temperature decreased to 34.6-36.5 °C at the end of the fermentation which was concluded after 7.6 h to 8.4 h. Sugars were consumed during the fermentation but it remained 12.9 to 16.57 g/L of reducing sugars and 8.02 to 9.12 °Brix of TSS in the final product. Ethanol content increased from 0.02-0.35 % (v/v) in the wort to 3.5-4.59 % in the beer. The oxalic, citric, tartaric, malic, lactic, fumaric and propionic acids were found in the wort and in tchapalo and increased or decreased during fermentation differently from one site to another. But, the acetic acid was not always detected in both the wort and the beer.

In Côte d’Ivoire, Cassava roots are mainly processed into attiéké, a kind of fermented cassava semolina, dried and steamed. This food, widely consumed, is produced by women according to a traditional technology requiring several hard operations. When the dough is not immediately processed into attiéké, it rots. Therefore, an improved process involving washing and storage of the fermented dough in a closed bucket was tested. This process lead to a stabilized dough which could be preserved for at least four weeks. The cyanide content in this dough represented 25% of the traditional one’s (39.50 ± 0.8 mg/kg). Both dough were safe of Enterobacteria. They mainly contained lactic acid bacteria (1 to 1.7×108 cfu/g) which grew during the stabilized dough storage. Attiéké from this dough was similar to the traditional attiéké. As stabilizing the fermented dough, the new process should encourage the growth of attiéké production efficiency, the producer incomes and cassava production increase.