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Aims: Contamination with filamentous fungi reduces the quality of cocoa beans and poses a health risk for consumers due to the potential accumulation of mycotoxins. The aim of this study was to develop antifungal Bacillus cultures for cocoa beans fermentation. Methods and Results: Antifungal activity of 7 Bacillus isolates was investigated using overlay technique. Solid culture media inoculated with bacterial and fungal isolates were cultivated under aerobic conditions at 30 ºC for 5 days. The Bacillus strain with strong antifungal activity was studied and inoculated to 18 kg box fermentations cocoa beans in Cote d'Ivoire in three time-independent replications each including a spontaneous control fermentation. The comparison of inoculated and spontaneous fermentation processes revealed that the Bacillus thuringiensis strain ATCC 10792 don't affected the fermentation process and cocoa bean quality. The anti-fungal in vivo assays revealed that the Bacillus thuringiensis strain ATCC 10792 completely inhibited growth of all fungi on the surface of cocoa beans. The result showed that sensory evaluation of chocolates is not significant differences for all treatment. The sensory evaluation of control and chocolates made from the inoculated cocoa beans with Bacillus showed excellent sensory quality, demonstrating that Bacillus thuringiensis strain ATCC 10792 did not affect aroma, texture and appearance of chocolate. Conclusion: From this study, it is revealed that the addition of Bacillus thuringiensis strain ATCC 10792 during fermentation cocoa beans suppress fungal growth and improve the quality of cocoa beans. Therefore, the anti-fungal culture Bacillus thuringiensis strain ATCC 10792 is recommended for future applications and its capacity to limit fungal growth during industrial-scale cocoa bean fermentation should be investigated in further studies.

Aims: Mold contamination of foods especially by mycotoxin producing fungi is not only a global food quality concern for food manufacturers, but it also constitutes a high risk for human and animal health resulting in massive economic losses globally. This study investigated the effect of Lactic Acid Bacteria (LAB) on the growth of Aspergillus carbonarius strains and their production of ochratoxin A (OTA). Methodology: Seven fresh coffee cherry and 9 dry coffee cherry samples were collected from Man, Daloa and Akoupé 3 main coffee producing regions in Côte d’Ivoire. LAB were isolated from fresh coffee cherries while mold strains were from both fresh and dry coffee cherry. The inhibitory effect against mold growth and the ability for OTA removal of selected LAB strains were tested successively in vitro and then during coffee cherry primary postharvest processing before evaluating their influence on sensory quality of beverage. OTA production ability of molds strains are studied using both solid (CYA) and liquid (CYB) Cazapeck Yeast medium. Results: About 34 fungal isolates belonging to Aspergillus and Penicillium genus were studied for their OTA production using the agar plug technique and HPLC-FD. Five A. carbonarius strains were capable of OTA production between 15.9 and 83mg.kg-1.Out of seven isolates of Lactobacillus plantarum, two were successful in inhibition of mycelial growthproduced fungicidal activity; five were successful in retarding it produced fungistatical activity All of L. plantarum isolates exhibited OTA reduction ability at about 99 %. The inoculation of two highest anti-ochratoxigenic LAB to fermenting coffee cherries resulted in great inhibition of mold growth and OTA contents reduction varying from 63.2 to 82.2%. The addition of LAB to coffee cherries did not influence the sensory attributes of the beverages produced thereof. Conclusion: This study highlighted that LAB are very promising biological candidates for reduction of mold contamination and removal OTA from coffee cherry during primary postharvest processing.

Fungal toxins can have various adverse health effects, including carcinogenic, teratogenic or hepatotoxic impacts. In addition, fungal alteration has also a negative impact on agricultural plant production. The use of chemical fungicides to control mycotoxin contamination is increasingly controversial and regulated. More environmentally friendly methods are therefore being explored. Essential oils, as compounds extracted from plants, are liquids whose specific aromatic compounds give each essential oil its own unique characteristics. Due to their rich chemical composition, essential oils (EOs) have many interesting properties, including antifungal activities. The objective of the present study was to analyze volatile chemical composition of EOs (Cymbopogon schoenanthus, Cymbopogon nardus and Eucalyptus camaldulensis) by GC/MS and to investigate their effects on the growth, sporulation and mycotoxin production of Aspergillus flavus, Aspergillus carbonarius and Fusarium verticillioides (aflatoxin B1, ochratoxin A and fumonisin B1, respectively). In addition, EOs influence on aflatoxin B1 (AFB1) and fumonisin B1 (FB1) biosynthesis pathways was explored using real-time qRT-PCR. The results obtained in vitro, by direct contact with the EOs and by diffusion of their volatile compounds, showed that the essential oils had inhibitory effects on the growth and the production of mycotoxins of the 3 fungal strains and modified the expression of some toxin synthesis genes. We conclude that the recorded effects were dependent on the combined effects of the EOs type, the fungal strains and the doses studied.

The antifungal and antiaflatoxinogenic activities of the essential oils (EOs) from the leaves of

The aim of this study was to evaluate the interactions between wheat plant (spikelets and straws), a strain of mycotoxigenic pathogen Fusarium graminearum and commercial biocontrol agents (BCAs). The ability of BCAs to colonize plant tissue and inhibit the pathogen or its toxin production was observed throughout two phases of the life cycle of pathogens in natural conditions (colonization and survival). All evaluated BCAs showed effective reduction capacities of pathogenic traits. During establishment and the expansion stage, BCAs provoked an external growth reduction of F. graminearum (77–93% over the whole kinetic studied) and mycotoxin production (98–100% over the whole kinetic studied). Internal growth of pathogen was assessed with digital droplet polymerase chain reaction (ddPCR) and showed a very strong reduction in the colonization of the internal tissues of the spikelet due to the presence of BCAs (98% on average). During the survival stage, BCAs prevented the formation of conservation perithecia of the pathogen on wheat straw (between 88 and 98% of perithecia number reduction) and showed contrasting actions on the ascospores they contain, or perithecia production (−95% on average) during survival form. The mechanisms involved in these different interactions between F. graminearum and BCAs on plant matrices at different stages of the pathogen’s life cycle were based on a reduction of toxins, nutritional and/or spatial competition, or production of anti-microbial compounds.

This research describes on-farm-inoculated cocoa bean fermentation with two selected strains of high aroma-producing Saccharomyces cerevisiae isolated from wine fermentation and their effects on volatile profile of resulted raw cocoa material and sensory characteristics of chocolates produced. Both strains produced suitably flavour-active esters, aldehydes, ketones and pyrazines in raw cocoa. Inoculation of S. cerevisiae at 0.5 g kg−1 significantly improved the volatile profile of raw cocoa beans and enabled production of chocolate with enhanced intense fresh fruits and floral notes. Chocolate produced thereof presented better overall quality attributed whatever the fermentation time in comparison to the chocolate issued from spontaneous fermentation. Our results suggested the ways of using selected enhanced yeasts as S. cerevisiae for on-farm implementation of bean fermentation as promising alternative possibilities to improve the cocoa fermentation process, desirable flavourful raw cocoa material and high-aroma-quality chocolates produced.

International audience; Ochratoxin A (OTA) in coffee is associated with serious health problems and significant economic loss. The state of Chiapas is the top coffee producer in Mexico, accounting for 41.3% of the national production, and the second largest organic coffee-producing area worldwide. Due to the lack of information about the OTA content in Chiapas coffee, 100 coffee samples from Chiapas were collected and classified according to their variety, type (roasted or nonroasted), processing and cultivation, in the 2017/2018 cycle. The average OTA concentration in 97 of the analyzed samples was 0.41 μg/kg. OTA was not detected in 52% of the samples; in 45% of the samples, the concentration ranged between 0.05 and 3.4 μg/kg, below the limit of European regulations (

Most of volatile flavour compounds occurred during the cocoa postharvest operations including pod storage and fermentation whom effects on these metabolites were aimed by the present study. Three different spontaneous fermentation treatments were performed on the farm, and the main isolated yeasts were identified using PCR-DGGE technique. Fermented cocoa beans were solar-dried, and their flavour compounds were identified using solid phase microextraction technique–gas chromatography–mass spectrometry. The main results showed that Pichia kudriavzevii was common yeast involved in the cocoa fermentation. Thirty flavour precursor compounds grouped into six chemical families including alcohols and pyrazines were identified in raw cocoa samples. ACP showed that short durations of pod storage and fermentation promote the formation of flavour precursors of cocoa. No spontaneous cocoa fermentation treatment influenced the occurrence of aroma compounds. The generation of flavour compounds depends only on the pod storage and the fermentative microorganisms of cocoa.

The objective of this study was to identify the dominant bacterial flora linked to the hygiene of dried and smoked fish in different geographical locations and to determine the presence of pesticide residues on the processed fish. Fish species were listed and collected. The bacterial ecology of dried and smoked fish from the northern zone of Cameroon was probed using a molecular technique employing variable regions of 16S rDNA profiles generated by PCR-DGGE (Polymerase Chain Reaction-Denaturing Gradient Gel Electrophoresis). The bacterial species were obtained by sequencing the PCR-DGGE bands and the pesticide residues by Chromatography coupled with mass spectrometry (GC-MS / MS), tested on 11 fish samples. Fifty three percent of the fish were smoked. Three types of pesticides have been identified on the dried fish samples. Among them, there were Cypermethrin (15 to 3600 µg/kg), Chlorpyrifos (19 to 8800 µg/kg) and Profenophos (62 to 92 µg/kg). The analysis of 16S rDNA profile and DNA sequencing revealed the presence of 32 bacterial species grouped into 22 genera. Dried fish were the most contaminated. Species such as Vagococcus carniphilus, Kurthia gibsonii, Lysinibacillus endophyticus, Macrococcus caseolyticus and Bacillus atrophaeus were present in the samples from all the locations. On a general note, the fish samples are of poor microbiological and sanitary quality.

High-performance liquid chromatography with diode array (HPLC-DAD) and liquid chromatograph triple quadrupole mass spectrometry (HPLC-MS/MS) were used to characterize raw and fermented coffee pulps in terms of their phenolic composition and caffeine content. The qualitative analysis showed no significant differences between the raw and the fermented pulps. Free hydroxycinnamic acids (HAs) were mainly chlorogenic acids, with 5-caffeoylquinic acid as the major compound. Bound HAs released caffeic acids during alkaline hydrolysis, and no bound ferulic and p-coumaric acids were detected. The fermentation process allowed the detoxification of the pulp from caffeine by 50%, while significantly reducing the amounts of residue by 64%. Moreover, the fermented products could be further processed to provide high added-value molecules with potential industrial applications, providing a new source of income for the small coffee producers.

The management of microbial contamination is an important issue in spice trade. For common domesticated black pepper (Piper spp.), the control relies mainly on post-process decontamination. The aim of the present study was to examine microbial contamination of wild pepper (Piper borbonense) from Reunion Island and investigate the effects of different processing paths on microbiological quality and fungal ecology. The fresh pepper microbial counts ranged from 4.6 to 6.8 log CFUg−1. Blanching had a positive significant impact on the microbiological quality of pepper whereas sweating led to microbial growth up to 5 log CFUg−1 and, therefore, should be avoided. Microbial counts for dried pepper were 1.33 log CFUg−1; 3.37 log CFUg−1; 1.67 log CFUg−1 and 1.3 log CFUg−1 for coliforms, TAMB, Staphylococcus, yeast and moulds, respectively. Potential mycotoxin producers were identified from pepper samples but aflatoxins and ochratoxin A levels detected were far below the regulation limits. The initial diversity of fungal contamination is prominent for the final quality of pepper in contrast to the impact of processes. The revisited wet process (blanching then drying), which positively affected all microbial loads, could be a good option for pepper transformation.

Ochratoxin A (OTA) is a secondary metabolite produced by fungal pathogens such as Penicillium verrucosum, which develops in food commodities during storage such as cereals, grapes, and coffee. It represents public health concerns due to its genotoxicity, carcinogenicity, and teratogenicity. The objective of this study was to evaluate the ability of actinobacteria and their metabolites to degrade OTA and/or to decrease its production. Sixty strains of actinobacteria were tested for their ability to prevent OTA formation by in vitro dual culture assays or with cell free extracts (CFEs). In dual culture, 17 strains strongly inhibited fungal growth, although it was generally associated with an increase in OTA specific production. Seventeen strains inhibited OTA specific production up to 4% of the control. Eleven actinobacteria CFEs reduced OTA specific production up to 62% of the control, while no substantial growth inhibition was observed except for two strains up to 72% of the control. Thirty-three strains were able to degrade OTA almost completely in liquid medium whereas only five were able to decrease it on solid medium, and two of them reduced OTA to an undetectable amount. Our results suggest that OTA decrease could be related to different strategies of degradation/metabolization by actinobacteria, through enzyme activities and secretion of secondary metabolites interfering with the OTA biosynthetic pathway. CFEs appeared to be ineffective at degrading OTA, raising interesting questions about the detoxification mechanisms. Common degradation by-products (e.g., OT&alpha, or L-&beta, phenylalanine) were searched by HPLC-MS/MS, however, none of them were found, which implies a different mechanism of detoxification and/or a subsequent degradation into unknown products.

The endogenous alpha-galactosidase activity of cowpea seeds was characterized and modelled assuming Michaelian behavior. The aim is to use the resulting knowledge to optimize alpha-galactoside degradation during the soaking-cooking process. In this study, the alpha-galactosidase enzyme from Wankoun cowpea was extracted and its enzymatic activity was analyzed as a function of temperature, pH and the presence of some inhibitors. Enzymatic activity was optimal around 35 °C and a pH of 5.8. Activation and inactivation energy was evaluated at 50 ± 3 and 103 ± 9 kJ.mol−1, respectively. The strongest inhibitor was galactose with an inhibition constant KI of 0.28 ± 0.03 mM. Incubation of the enzyme extract with alpha-galactosides revealed a 10-h lag phase in the early stages that could be due to low pH, the action of inhibitors including galactose and the biosynthesis of alpha-galactosides. After the lag phase, the degradation of each alpha-galactoside occurred without the appearance of any intermediary product. The degradation of alpha-galactosides was observed with a Km of 1.7 ± 0.3 mM for raffinose; 3.6 ± 0.6 mM for stachyose and 15.9 ± 0.1 mM for verbascose. A long soaking step around 35 °C is suggested to maximize the alpha-galactosides enzymatic degradation.

A simple, fast and ecological analytical method using a semi-automatic fat extractor and HPLC-FLD (fluorescence detection) for determination of polycyclic aromatic hydrocarbon markers i.e. benzo(a)anthracene (BaA), chrysene (Chr), benzo(a)pyrene (BaP) and benzo(b)fluoranthene (BbF) in cocoa butter has been validated. Validation's procedure performed out in concordance with French standard NF V03-110 (2010) was based on existing polycyclic aromatic hydrocarbon (PAH) determination methods in various smoked foodstuffs and edible vegetable oils. Determination of correlation coefficients for specific PAHs ranged from 0.9992 to 0.9998. Respective values of limits of detection were 0.010, 0.011, 0.033 and 0.029 μg kg−1 and those of quantification were 0.035, 0.038, 0.111 and 0.098 μg kg−1 for BaA, Chr, BbF and BaP. Both values of repeatability and intermediary precision tests coefficients of variation were less than 5%. Recovery scores of four PAH markers matched EU standard 836/2011 recommendations. Sum of four PAH markers (BaA, Chr, BbF, BaP) contents varied from 5.42 ± 0.58 to 11.37 ± 0.01 μg kg−1 whereas those of BaP was comprised between 0.26 ± 0.00 and 1.75 ± 0.13 μg kg−1 in 20 cocoa butter samples extracted from raw cocoa bean stored at Ivorian cocoa farmer levels.

In a sustainable development concern, the agricultural practices notably those to control the pathogenic and/or mycotoxigenic fungi that maintain the quality and the abundance of crops with respecting the ecosystems and public health are indispensable. Our study focuses on evaluating the biocontrol potential of the actinomycete microflora of some organic amendments against the phytopathogenic and mycotoxigenic Fusarium verticillioides. The inhibitory effect was assessed in term of growth and mycotoxin production (fumonisin FB1 and FB2) of F. verticillioides in the presence of amended soils and selected antagonist agents from the amendments. Results demonstrated that the amended soils with different organic amendments exhibited a higher inhibition rate of Fusarium verticillioides growth than the reference soil. They were able to inhibit the fungal pigment and spore productions which are the major mean of survival and dispersion of this fungus. The fumonisin production was strongly reduced by the metabolites produced by the amended soils’ microbiota, up to 68.7% and 92.5% for FB1 and FB2 respectively. Actinomycete strains isolated from these amendments were identified as Streptomyces and were also tested for their antifungal potential. The fungal growth was reduced up to more than 60% in the presence of extracellular metabolites of several Streptomyces strains. In confrontation assays, most of the Streptomyces strains inhibited strongly both fungal growth and fumonisin production. The FB1 and FB2 amounts were decreased at best, by up to 87.5% and 98.2% respectively, depending on the actinomycete strains and fungal culture time. These results are promising for the use of these biocontrol agents, and especially some actinomycete strains, as tools to reduce fumonisin contamination in cereal crops and derived products.

Gowe is a very popular traditional fermented and non-alcoholic cereal beverage in Benin. The purpose of the present study was to characterize the physical-chemical properties, nutritional and anti-nutrient composition, microbiological safety and mycotoxin occurrence in the various types of gowe. Six to nine samples from four types of technologies were analyzed for the various aspects of quality. Proximate composition, physical properties (particle size, viscosity), nutritional (amino-acid profile) and anti-nutritional (tannin, phytate, and cyanide levels) properties of gowe resulting from the different traditional processes are quite similar except for the physical properties, the differences of which originate from the raw materials and the diverse cooking conditions. The main hazard of traditional gowe are potential mycotoxin contamination, and presence of cyanogenic compounds, which are linked to raw material contamination and the malting step, and occurrence of E. coli and Enterobacteriacae (gowe is free from other pathogens), linked to inappropriate handling and to the packaging material. The main defects are low α-amylase activity of malt linked to poor control of the malting process, low content of several essential amino-acids in the raw materials and which is deteriorated by the cooking step. Several potential solutions are discussed for paving the way for upgrading and re-engineering this process.

Cereals products enriched with leguminous or oleaginous are used in Burkina Faso as food complement or to avoid infant malnutrition. Infant formulas from cereals are consumed as food supplements after the weaning age. They are produced in Burkina Faso with a mixture of several cereals (maize, millet, rice, or sorghum), leguminous (bean), oleaginous (peanut, soya or sesame), sugar or salt and sometimes milk powder. The production is artisanal or semi-industrial. These infant foods from cereals should be free from mycotoxins and pathogenic bacteria. The objective of this work was to determine the occurrence of mycotoxins like aflatoxins, ochratoxin A and fumonisins in infant formulas and grains in Ouagadougou (Burkina Faso). The mycotoxins (aflatoxins, ochratoxin A and fumonisins) were determined by HPLC-FLD in 248 samples of infant formulas produced by the Recovery and Nutrition Education Centers (CRENs) and sold on the market places in Burkina Faso. Results showed that the majority of samples of infant formulas presented high levels of mycotoxins. The frequency of contaminated samples by aflatoxin B1, ochratoxin A and fumonisins in analyzed samples were 83.9% (167/199), 7.5% (15/199) and 1.5% (3/199), respectively. The highest values registered in infant formulas were 900, 6 and 3 times higher for aflatoxin B1 (EU limit: 0.1 μg/kg), ochratoxin A (EU limit: 0.5 μg/kg) and fumonisins (EU limit: 200 μg/kg), respectively, than the EU regulation limits (1881/2006). This study presents the first results concerning the safety assessment of infant formulas regarding mycotoxins in Burkina Faso.

'Kankankan' is a popular spice powder used to season roasted meat in Côte d'Ivoire. However, produced in a traditional way, the conditions of production and storage of kankankan favour the proliferation of mycotoxin-producing fungal strains. The aim of this study was to carry out an inventory of mycotoxin contamination of this spice powder and to assess risk exposure to consumers. In total, 75 samples of kankankan were collected from wholesalers (6), sellers of kankankan in the markets (35) and sellers of roasted meat (34) across three municipalities of Abidjan, the economic capital of Côte d'Ivoire. Ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) was used to detect and quantify nine different mycotoxins. Dietary exposure was calculated by using estimated daily intake (EDI), whereas risk characterisation was assessed using the margin of exposure (MOE) approach. Aflatoxins and fumonisins were found in 99% of samples assessed, while contamination with beauvericin was proportionally lowest (28%). At all the three types of actors within the food production chain (wholesalers, kankankan sellers and roasted meat sellers) the mean concentrations of aflatoxin B1 (AFB1) in samples exceeded the European standard for spice mixtures, with concentrations reaching up to 502 µg/kg. The estimated daily intakes of aflatoxins observed in the different populations were above the recommended level of 0.017 ng kg−1 b.w. day−1. The MOES values for adolescents and adults were 8.10 and 12.78, respectively, well below the safe margin of 10,000. The co-occurrence of mycotoxins in kankankan samples together with high aflatoxin exposure to consumers represent a potential risk to public health, calling for immediate risk management and education of kankankan producers and consumers.

The actinobacteria Streptomyces sp. AV05 appears to be a potential biocontrol agent (BCA) against mycotoxigenic fungi. It was found to significantly inhibit F. verticillioides growth and mycotoxin production during their co-cultivation. F. verticillioides growth was durably affected while the decrease of the toxin production levels was reversible, suggesting different BCA actions. The study of both transcriptomes brought useful information on the microbial interaction. RNA-seq data indicated that the dual interaction modified genetic expression of both microorganisms as 18.5 % of the genes were differentially expressed for the fungus against 3.8 % for the actinobacteria. Fungal differentially expressed genes (DEGs) were equally up and down regulated while bacterial ones were mainly upregulated. We especially focused the analysis of DEGs on fungal defense reaction to bacterial attack. For example, if this potential BCA implements a strategy of antibiosis with the over expression of 'siderophore-interacting protein' linked to the production of bacteriocins, the fungus in a state of stress is able to adapt its metabolism by up-regulation of amidase. It could correspond to the induction of resistance gene clusters and suggest a detoxification process. Moreover fumonisins-related pathway appears underexpressed in the presence of Streptomyces that explain the reduction of fumonisin accumulation observed.

In this study, coffee pulp was used as carbon source in solid-state fermentation to produce a phenol-rich extract for industrial applications. Fermentations were carried out at laboratory (0.4 kg), semi-pilot (12 kg) and pilot (90 kg) scales in presence of 2.5 g kg−1 yeast strains and with three different coffee pulp materials. The extract stability was investigated using different stabilizing agents: SO2, ascorbic and acetic acids. Then, a study was conducted to determine the effect of ultrasound treatment on extraction yields. Results showed that higher concentrations of chlorogenic acids were obtained with fermentation without ultrasound treatment and by adding sulfite at 0.5 wt% at 8 h of fermentation. Despite of variations in coffee pulp composition, the process was validated at semi-pilot and pilot scales, providing an extract 400% richer in chlorogenic acids (600 mg kg of coffee pulp) and with lower sugar amounts to separate during the downstream processing. Universidad de Costa Rica/[735-A2-502]/UCR/Costa Rica UCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Agroalimentarias::Centro Nacional de Ciencia y Tecnología de Alimentos (CITA)

The effects of light at different wavelengths and photoperiod on growth and ochratoxin A production of Aspergillus carbonarius and Aspergillus westerdijkiae were studied: far-red (740 nm), red (625 nm), blue (445 nm), and UV-A (366 nm). Fungal growth was not significantly affected by photoperiod or light wavelength; the only exception was A. westerdijkiae which showed reduced growth under UV-A light (366 nm). Short-wavelength blue light (445 nm) and UV-A light caused a reduction in ochratoxin A production of both fungal species. However, long-wavelength red light (625 nm) and far-red light (740 nm) reduced ochratoxin A production only in A. westerdijkiae but not in A. carbonarius. It is believed that this difference in reactivity to light is due to differences in the melanin content of the two fungal species: A. carbonarius is a black fungus with higher melanin content than A. westerdijkiae, a yellow fungus. Other possible explanations for the reduction of ochratoxin A production by light were also discussed.

White Kenley is a traditional stiff dumpling produced from fermented dehulled maize grains in Ghana. The physico-chemical modifications which occur during combination of various steeping (12, 30 and 48 h) and fermentation (0 h, 12 h and 24 h) times were assessed to study the impact of these unit operations on the quality of white kenkey . Water uptake by soaked grains and the release of metabolites were followed during grains steeping and particle size distribution after milling was determined. Steeping time exceeding 24 h was required to produce a fine wet milled flour while water uptake was completed after 8–10 h. This was parallel to hydrolysis of proteins and/or hemicelluloses which occurred after 16 h. Changes in acidity and glucose content were determined in the grain after steeping and in the dough after fermentation. The texture of the kenkey was determined using a texture analyzer. Increases in acidity were higher during dough fermentation than in steeping. Stickiness of the white kenkey decreased consistently with steeping time. Principal Component Analysis showed that a combination of long steeping and short fermentation times gives white kenkey with low stickiness (and high fineness), low acidic taste and low fermented odour.

This study aimed to assess aflatoxin and fumonisin intake through corn tortilla consumption in Veracruz city. Between October 2013 and February 2015, a total of 120 corn tortilla samples (2 kg samples, 40 samples per year) were randomly collected. Aflatoxins and fumonisins were quantified by high performance liquid chromatography coupled with a fluorescence detector. A probability density function (PDF) was used for describing corn tortilla intake, body weight of the Veracruz city population, mycotoxin content of corn tortilla samples and estimated mycotoxin daily intake. The Monte Carlo method with 10,000 iterations was employed to assess the population exposure risk. The highest level of total aflatoxins (AFT) was 22.17 μg kg−1, and 526.6 μg kg−1 for fumonisins B1 plus B2, with 85% and 90% of contaminated samples respectively. Up to 69.7 % of the population was estimated to consume a higher aflatoxin dose than that recommended by the JECFA (1 ng kg−1 of body weight per day); it was found that the recommended dose was exceeded to a greater extent in the male population, due to higher consumption of corn. The risk of fumonisin intake was less than 5 % due to the low presence and levels of these toxins in corn tortillas. The results suggest that corn tortilla consumers are at dietary risk caused by AFT contamination; this information should be considered when taking action to protect public health.

The study investigated the occurrence of natural fungal contaminants in food commodities The prevalence of diarrheal diseases in children aged from 6 to 24 months in Burkina Faso is 38%. These diarrheas may be due to the consumption of contaminated weaning food. Therefore, the microbiological quality of follow up infant flours used as supplement foods is a key-point to reduce children diseases. In this study, the microbiological safety of locally-produced infant flours was investigated. One hundred and ninety-nine (199) samples were collected mainly in retails outlets and in Recovery and Nutrition Education Centers. According to the Burkina Faso regulations, microbiological analyses were carried out for Total Aerobic Mesophilic Flora (TAMF), thermotolerant coliforms, Salmonella spp. and yeasts/molds. The bacterial and fungal isolates were identified using phenotypic and genotypic methods and the study of the production of mycotoxins was carried out from the fungal isolates. In collected samples, the TAMF count ranged from 0 to 1.8 × 106 CFU/g with a total average of 6.3 × 104 CFU/g. About 2% of the samples had a microbial load exceeding the standards (105 CFU/g). No Salmonella spp. was isolated in the final infant flours. However, the presence of Enterobacteriaceae (Klebsiella spp. Enterobacter spp. and Cronobacter spp.) was detected and molecular characterization revealed also the presence of fungal species of the genus Aspergillus spp., Penicillium spp. and Fusarium spp. Some of these species were found to produce aflatoxins, ochratoxin A and fumonisins, which are potential carcinogenic toxins. These results demonstrated the need for a preventive approach based on the application of Hazard Analysis Critical Control Point in the food industry to ensure food safety of infant flours in Burkina Faso.

Ochratoxin A (OTA) is a nephrotoxic, teratogenic, immunotoxic, and carcinogenic mycotoxin which is produced in tropical zones mainly by Aspergillus carbonarius, A. niger, A. ochraceus, and A. westerdijkiae. A. ochraceus and A. westerdijkiae species are phenotypically and genomically very close but A. westerdijkiae produce OTA at a very higher level than A. ochraceus. These species have been differentiated recently. The DNA primer pairs which were drawn so far are not specific and a genomic region of the same size is amplified for both species or they are too specific, and in this case, the DNA of a single species is amplified. To help preventing OTA contamination of foodstuffs, the PCR‐DGGE (Denaturing Gradient Gel Electrophoresis) method was used to discriminate between A. ochraceus and A. westerdijkiae DNA fragments of the same size but with different sequences and thus faster access to a diagnosis of the toxigenic potential of the fungal microflora. The proposed methodology was able to differentiate A. westerdijkiae from A. ochraceus with only one primer pairs in a single run. A calibration based on initial DNA content was obtained from image analysis of the DGGE gels and a method of quantification of the two strains was proposed.

Various chemical compounds in green coffee beans are precursors of coffee beverage sensory attributes. The hypothesis was that those chemical compounds would vary with microclimate over the vertical plant profile of coffee plants. The plants of the cultivar IAPAR 59 were grown in two high plant densities (6000 and 10,000 plants ha−1) under rectangular and square planting patterns. Coffee beans were collected from three canopy strata. Chemical compounds and chlorogenic acid isomer (CGA) contents were determined by near infrared spectroscopy and ultra-performance liquid chromatography, respectively. The free-choice profile technique was employed to estimate the sensory attributes of coffee beverage. Brightness, transparency appearance, typical coffee color and aroma, tastes as sweet, acid, astringent and bitter, and full-bodied texture were attributes detected by panelists. Plants cultivated under lower plant density had lower leaf area index indicating lower self-shading than under higher plant density. Coffee beans originated from the inferior stratum of higher density had the lowest concentrations of 5-caffeoylquinic acid (5-CQA), while the inverse situation occurred in their upper strata. Strata of lower planting density were associated to high levels of all CGA isomers. The coffees cultivated under higher density showed high lipids and CGA isomers contents. Under lower density, beans had low concentration of sucrose, proteins, and caffeine and high of CGA isomer contents. The beverage sensory attributes depended on the concentration of proteins, lipids, and sucrose in combination to CQA isomers in beans, varying over the vertical profile and planting designs of coffee plants.

The prevalence of diarrheal diseases in children aged from 6 to 24 months in Burkina Faso is 38%. These diarrheas may be due to the consumption of contaminated weaning food. Therefore, the microbiological quality of follow up infant flours used as supplement foods is a key-point to reduce children diseases. In this study, the microbiological safety of locally-produced infant flours was investigated. One hundred and ninety-nine (199) samples were collected mainly in retails outlets and in Recovery and Nutrition Education Centers. According to the Burkina Faso regulations, microbiological analyses were carried out for Total Aerobic Mesophilic Flora (TAMF), thermotolerant coliforms, Salmonella spp. and yeasts/molds. The bacterial and fungal isolates were identified using phenotypic and genotypic methods and the study of the production of mycotoxins was carried out from the fungal isolates. In collected samples, the TAMF count ranged from 0 to 1.8 × 106 CFU/g with a total average of 6.3 × 104 CFU/g. About 2% of the samples had a microbial load exceeding the standards (105 CFU/g). No Salmonella spp. was isolated in the final infant flours. However, the presence of Enterobacteriaceae (Klebsiella spp. Enterobacter spp. and Cronobacter spp.) was detected and molecular characterization revealed also the presence of fungal species of the genus Aspergillus spp., Penicillium spp. and Fusarium spp. Some of these species were found to produce aflatoxins, ochratoxin A and fumonisins, which are potential carcinogenic toxins. These results demonstrated the need for a preventive approach based on the application of Hazard Analysis Critical Control Point in the food industry to ensure food safety of infant flours in Burkina Faso.

The study investigated the mycological safety of Bambara groundnut (Vigna subterranea (L.) Verdc) from Southern Africa. Conventional and molecular methods identified aflatoxin-producing Aspergillus flavus in Bambara seed while a modified QuEChERS method for mycotoxin detection confirmed the presence of aflatoxin in the flour. Flour samples obtained by milling, roasting and milling, and spontaneous fermentation stored for 30 days at simulated tropical conditions (30 ± 1 °C, 85 ± 2% relative humidity) were analyzed for changes in fungal counts, water activity and aflatoxin production. A co-occurrence of Aflatoxin (AF) B1 (0.13–6.90), AFB2 (0.14–2.90), AFG1 (1.38–4.60), and AFG2 (0.15–1.00) was recorded in the flour samples. Over the storage period, there was significant (p ≤ 0.05) increase in the water activity of roasted Bambara groundnut flour (0.09–0.95), fermented Bambara groundnut flour (0.34–1.02), and Bambara groundnut flour (0.42–0.89); and in the fungal counts irrespective of the processing method. Roasting at 140 °C for 20 min completely degraded aflatoxin in the seeds. Fungal and mycotoxin contamination of Bambara groundnut raises concerns on health of consumers.

International audience

Aims: 104 samples were collected from the west region and the coastal plain of Cameroon during two coffee campaigns, 2009 and 2010. Two coffee processes were evaluated (wet and dry processes) at different stages from harvesting to storage. Study Design: Food contaminants. Place and Duration of Study: Food Microbiology Laboratory, Department of Food Science and Nutrition (ENSAI) University of Ngaoundere; UMR 95 Qualisud, CIRAD of Montpellier, between May 2009 and September 2012. Methodology: Fungi profile was evaluated by direct plating techniques and identified using morphological and molecular tools. OTA levels were analyzed using HPLC technique after extraction and filtration using an immunoaffinity column. Results: Results obtained revealed an overall percentage of fungal contamination between 60-92% in 2009 and 70-90% in 2010. There was no ecological difference in the composition of ochratoxigenic species present in five sites. Coffee beans sampled in 2009 had a colonization incidence of 18-40% A. carbonarius, 12-22% A. niger, 3-15% A. ochraceus while those of 2010 had a colonization incidence of 15-30% A. carbonarius, 35-40% A. niger, and 2-7% A. ochraceus. Fungal diversity was not correlated with the geographical origin, coffee cultivar and processing method. There was no difference between the processes studied in terms of occurrence of ochratoxigenic fungi. OTA levels were mostly below the recommended standards although some isolated cases of extreme contamination were observed in 2009. A higher level of OTA was detected in the presence of A. niger, A. carbonarius and A. ochraceus than when only A. niger was present. Conclusion: The important fungi with the potential to produce OTA in Cameroonian coffee beans are A. carbonarius and A. niger. These two species were predominant on each type of coffee beans. It was also observed that once a toxigenic strain was isolated from a coffee sample, the sample contained OTA. (Resume d'auteur)

Introduction Ochratoxin A (OTA) is a toxic secondary metabolite produced by fungi of the genera Aspergillus and Penicillium. It has been shown to have carcinogenic and immunotoxic properties in rats and to be responsible for human and animal kidney pathologies. OTA content in coffee was shown to be closely link to harvesting conditions, postharvest processing conditions and especially dry processing, storage and transportation conditions. Purpose Fairly little is known about the conditions for contamination by fungi responsible for OTA production, their propagation and conditions for OTA production. Biodiversity and dynamics of fungal populations linked to OTA production could be studied by PCR-DGGE genetic fingerprinting with the aim to understand the effects of postharvest processing on the microbiota. Results DGGE fingerprints analyzed by multivariate analysis showed an evolution of the fungal microflora of coffee during the different stages of the postharvest treatments (wet and dry processes) by extraction and amplification of 26S (yeasts) and 28S rDNA (filamentous fungi). PCR-DGGE stages were optimized: extraction and amplification, repeatability and sensitivity methodology applied to fungi were tested. Conclusion PCR-DGGE is a rapid molecular technique to monitor the dynamics of coffee microbial populations (fungi and yeast). Significance of study PCR-DGGE is a promising tool in order to investigate OTA production in coffee beans.

L’ochratoxine A (OTA) est une toxine cancerogene produite par certaines moisissures. Elle contamine de nombreux aliments et notamment le cafe dans lequel elle est retrouvee a toutes les etapes du parcours technologique du champ a la tasse. Cette etude a pour objet de faire le point sur les etapes critiques des procedes de transformation du cafe, que ce soit durant les traitements post-recolte ou pendant la transformation en produit consommable, en ce qui concerne sa contamination par l’OTA. La qualite et le type de traitements post-recolte ont une influence non negligeable sur le niveau de contamination en OTA des grains verts. Les defauts agronomiques (insectes et attaques fongiques) contribuent egalement a un niveau eleve d’OTA dans le cafe vert. Diverses etudes effectuees sur l’impact de la torrefaction mettent en evidence une degradation thermique de l’OTA. Toutefois, la contamination initiale des feves, le procede utilise et le degre de torrefaction influencent fortement cette degradation thermique et donc la concentration residuelle en OTA dans les grains torrefies. Finalement, il apparait que c’est la maitrise de la contamination en amont par de bonnes pratiques agricoles et par les traitements post-recolte qui est le plus sur gage de salubrite pour la boisson.

Attieke is produced and consumed throughout the entire territory of Côte d'Ivoire. It is a food made by lactic fermentation of cassava and prepared in advance. It is the first ready-to eat meal sold in the towns of Côte d'Ivoire and increasingly in other African countries. For those reasons, we studied the quantitative assessment of the microbiological risk associated with this product. The objectives were firstly to appreciate the microbiological quality of attieke sold on the markets of major cities, and secondly, to quantitatively assess risk for Clostridium perfringens in attieke. To achieve these objectives, a microbiological analysis of attieke samples sold on the open markets was carried out in order to enumerate C. perfringens and some indicator microorganisms of the microbiological quality of the food: Aerobic mesophiles, total coliforms, Escherichia coli and Staphylococcus aureus. A household survey was also conducted to estimate the daily attieke consumption per individual. Statistical analysis of the average concentration for each microorganism in attieke reveals a great variability generally highly significant (p < 0.01) between the markets. Some concentrations were exceeded the acceptable microbial limits. This was the case for E. coli (>102 cfu/g) at Daloa and Abengourou, and S. aureus on all areas or towns (>105 cfu/g) except Yamoussoukro. Concerning the results about the quantitative risk assessment for C. perfringens, 38% of servings sold contain concentrations exceeded the acceptable limit of 105 cfu/g for the readyto eat meals. Using Monte-Carlo simulations, the probability of ingesting a dose greater than 109 bacterias of C. perfringens varied between 1.27% and 2.80%. This means that for every 100 000 individuals consuming per day attieke sold in retail, 1270 to 2800 could be potential victims of foodborne illness outbreaks caused by C. perfringens only.

International audience

The recent public health issues affecting food chains have prompted health authorities to increase their vigilance concerning the presence of contaminants in staple foods. This change in position has led to the introduction of regulations (Regulations (EC) No. 1881/2006 and 149/2008 of the European Commission). Coffee, being one of the most widely consumed beverages in the world, is no exception and is now subjected to these provisions. The known origins of coffee contamination are: on one hand, pesticides used during culture and storage and, on the other hand, mycotoxines and polycyclic aromatic hydrocarbons (PAH) that arise from processes of drying and roasting.Pesticides are used in modern agriculture to reduce the impact of pests and diseases in crops. Nevertheless, pesticide residues in green coffee remain relatively limited during agricultural treatments. The maximum risk of contamination occurs during transportation and storage. Mycotoxins are toxic chemicals produced by certain fungi that grow on foodstuffs. Ochratoxin A (OTA) is the main mycotoxin found in coffee. It is a secondary metabolite produced by several toxigenic species of Aspergillus and Penicillium. It has been shown to have nephrotoxic, carcinogenic, teratogenic and immunosuppressive effects. The presence of OTA in coffee beans may be linked to environmental conditions and to post-harvest processing conditions. The polycyclic aromatic hydrocarbons found in coffee may be exogenous (contamination during drying) or endogenous (formation during roasting). PAHs are toxic and/or carcinogenic compounds. For each family of contaminants, the current knowledge, regulations and effective ways of limiting their contents are discussed.