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RATIONALE - Coffee is one of the main agricultural crops in the world. Raw coffee cherries can contain the mycotoxin ochratoxin A (OTA). OTA is produced by several species of Aspergillus and Penicillium. International coffee organizations pay more and more an attention on statutory limits for OTA in Coffee products (FAO, 2006). OTA contents need to be reduced in coffee cherries to as low as technologically control of mycotoxin by avoiding fungal growth and OTA production. METHODS - Identification of lactic bacteria (LAB) and Aspergillus carbonarius strains isolated from Ivorian coffee cherries were carried out using microbiological and molecular methods. Study of effect of cells and supernatant of liquid culture of L. plantarum strains were investigated on the growth of ochratoxinogenic A. carbonarius strain using various confrontation tests in vitro. Then, the best potential fungal growth inhibitor and OTA content reducing strains were inoculated with coffee cherries during post-harvest processing on farm. Fungal growth was measured by weighing the biomass during the incubation and at the end of coffee cherries drying. Samples of OTA contents reduction experiments were analysed by HPLC-FLD method (Sueck et al., 2019). RESULTS - Five OTA-producing A. carbonarius strains were detected. Sixteen isolates of LAB including 12 Lactobacillus plantarum strains, 2 Weissella confusa strains, 1 L. pentosus strain and 1 W. paramesenteroides strain. Ten strains of LAB showed potential activity with rates (17.3-79.1 %) against fungal growth and capacities to reduce OTA contents (6-96 %). Among these LAB, 7 strains of L. plantarum showed highest antifungal activities. Cells of LAB strains had highest inhibitory effect on fungal growth and reduction of OTA contents. On the farm, only the inoculation of L. plantarum D12 with coffee cherries result in reduction of OTA content without inhibition of fungal growth. CONCLUSION & PERSPECTIVES - The inoculation of specific L. plantarum with the coffee cherries on the farm results in decrease of OTA level without inhibition of fungal growth. Using L. plantarum D12 strain could allow to control and reduce to as low as biotechnologically promising and excellent way in coffee cherries and probably in other foodstuff. The further study may be performed on the comprehension of OTA reduction mechanism.

RATIONALE - Near infrared spectroscopy (NIRS) has been widely used for green coffees characterization and especially for the quantification of the main chemical constituents. The CIRAD database contains more than 2210 spectra and efficient calibrations for major constituents. However, this database is mostly constituted of Coffea arabica and C. canephora, which limits its representativeness. In order to enhance the database robustness, the analysis of wild coffee species has been undertaken. METHODS - Over 4 years, 462 seed samples, from 32 species, were collected on individual trees from the Coffea Biological Resources Centre in Réunion. Ground dried samples were analyzed for their absorbance spectrum using a FOSS 6500 monochromator (FOSS, Hillerod, Denmark). A selection, based on spectra, of the 90 most representatives samples was done using PCA and Mahalanobis neighborhood distances. The selected samples were analyzed for their caffeine, trigonelline, fat and chlorogenic acids (CGA) contents using standard analytical chemistry protocols. RESULTS - The distance threshold corresponding to the neighborhood was 0.55. The 90 samples came from 22 different coffee species. The caffeine content ranged from 0 to 3.3%, trigonelline from 0.25 to 1.52%, CGA from 0,22% to 10,53% and fat from 7.12% to 34,45% (dmb). The enhanced predicted models using this new data set present standard errors of 0.08%, 0.07%, 0.58% and 0.48% for respectively caffeine, trigonelline, CGA and fat. These performances are close to original models ones, with an increase of the content ranges, especially for fat. CONCLUSIONS & PERSPECTIVES - This study demonstrated the efficiency of the use of genetic diversity to enhance the robustness of the database. This approach lead to a real increase of the range for caffeine and fat contents. Thus, the resulting calibrations cover a larger range of values without significant losses of accuracy. The use of Mahalanobis distances permitted an efficient improvement of the calibrations representativeness with a limited number of samples. The new calibrations will be applied to the whole database in order to describe biochemical diversity in wild coffee species. The study will also be pushed forward to other chemicals such as fatty acid composition and diterpenes profiles.

One of the most common mycotoxin contaminating feed and foodstuffs is Ochratoxin A (OTA). OTA has a chronic toxic effect and proved to be mutagenic, nephrotoxic, teratogenic, immunosuppressive, and carcinogenic. Aptamer with their specific affinity for OTA was used in this paper to create an analytical technique. Several methods have been reported for the determination of OTA in foods. However, most of these methods could not be applied to a complex food as green coffee because the interfering native fluorescent products made the quantification very difficult. In this work, we mixed two separations based techniques to identify and quantify OTA in green coffee. Aptamer assisted ultrafiltration as separation technique based on the size of molecules was applied to separate the free OTA, the quantification of OTA was established by a high-performance liquid chromatography (HPLC-FD) with a limit of detection (LOD) of 0.05 ng/mL for OTA. Artificially contaminated green coffee displayed a good range of OTA recoveries up to 97.7%. This method can be applied to the quantitative determination of OTA in green coffee at levels below the maximum levels proposed by the European Commission for green coffee. It also confirm that aptamers can be used as biorecognition element in diagnostic assays with commercial application for mycotoxin analysis.

The 3C Ivoire EuropeAid project (2011â2015), set up a coordination committee in Ivory Coast to evaluate the effectiveness of sanitary controls, prevent sanitary risks and coordinate nationwide actions on food safety [1].This paper reports main findings: difficulties to apply regulations in Ivory Coast, to establish a national food safety agency, to implement a national health surveillance system, to set up a potential food safety label, training on food safety systems (HACCP, traceability, good hygiene practices), first experimental committee of national experts.Ivoirians are concerned by food safety hazards. All food samples collected in markets were contaminated by pathogens. Three of the main food consumed in the country: rice, maize, peanut were contaminated with mycotoxins, and aflatoxin levels in peanut paste were well above the EU limits. The decree creating the Ivorian agency was signed in late June 2016. Keywords: Food safety, Foodstuffs, Ivory Coast, National agency, Hazards, 3C Ivoire

Mycotoxins are toxic secondary metabolites synthesized by molds that contaminate many foods of plant origin, including cereals which are the first factor of consumer exposure to these molecules. In particular, the species Fusarium graminearum and Fusarium verticillioides are responsible for the production of mycotoxins belonging to trichothecene and fumonisin classes respectively. To fight against these fungi, an alternative strategy to phytosanitary products is the use of antagonistic microorganisms which by various mechanisms will reduce the progression of these fungi and limit the accumulation of mycotoxins. Actinobacteria show some of the most promising features for the biocontrol applications. Carrying a large toolbox of enzymes and active metabolites that allow them to settle in the soil environment, they are also able to interact directly with the plant. Our studies aim to propose a global approach to evaluate and to characterize the potential of actinobacteria isolated from amended soils. To this aim, our studies will span the control of wheat fungal diseases, from in vitro testing to in planta efficacy, and will also evaluate their technological properties for a future industrial production. Sixty actinobacteria strains were confronted against the mycotoxigenic fungi. Several isolates have shown promising antimycotoxigenic potential and have allowed us to select 10 strains for further investigations. In planta assays will be implemented to challenge our in vitro results. Finally, technological properties such as sporulation yield and resistance to conservation processes will be studied for the most promising strains. This will open new perspectives for the potential formulation of a biocontrol product. Moreover, the implementation of such protection methods requires a good knowledge of the biological mechanisms that govern the interaction between mycotoxinogenic molds and biocontrol agents, in order to favor the antagonistic phenomena but also to facilitate the selection of new biocontrol candidates according to the most promising processes. Thus, at the same time, a toolbox to decrypt the mechanisms of action is under development on 3 commercial agents. The impacts of these BCAs on pathogens are analyzed at the microscopic level, but also on the growth kinetics of the pathogens and their ability to produce mycotoxins under different conditions. Further studies on in vitro pathosystem will use omics to identify the genes and molecules differentially expressed during these interactions. The preliminary results show that in all the interaction combinations (pathogen-BCA), the BCA significantly reduce the growth of the pathogens. However, a great variability of interaction profiles is observed with in particular a strong impact of the nutrient source. For example, with a limiting nutrient source, T. asperellum causes a reduction in specific mycotoxinogenesis, while the opposite phenomenon is observed in a non-limiting nutritive source. Confrontation experiments will then be carried out on wheat spikelets in order to validate the hypotheses observed on synthetic medium and put the plant back at the heart of the experimental setup. In the long term, this highly integrative and multidisciplinary approach will provide elements of answers on the biological mechanisms involved in the biocontrol of mycotoxigenic fungi, the biological pathways involved in this interaction.

Biochars were produced from cashew nut shell at 400, 600 and 800°C. Production temperature significantly affected biochar properties and consequently the adsorption mechanisms of ochratoxin A. Biochars produced at higher temperatures had significantly higher specific surface areas, resulting in higher OTA adsorption ca-pacities. The isotherms and kinetics of the adsorption were used to identify the adsorption mechanisms. For the kinetics study, experiments were carried out after adjustment of the parameters influencing the system, such as pH, biochar quantity and OTA initial concentration. Experimental results were modelled according to isotherm equations representing Langmuir model and Freundlich model. Langmuir model matched best with the experi-mental data. The chemical surface reaction was fitted to a pseudo-second order equation, with very high re-gression coefficients.

Biochars were produced from cashew nut shell by pyrolysis on tubular oven at 400, 600 and 800°C.They were thenanalyzed and characterized (CHN, volatiles and pH);andwere tested at different pH (4.15, 6.54 and 9.05) under different adsorption conditions (filtration and stirring) for their ability tocapture aflatoxins and ochratoxin A (OTA). Above 25 mg of biochar in 5 mL of water-methanol mixturecontaining the mycotoxins (aflatoxins and OTA), all biochars adsorbedup to 100% of the aflatoxins at all pH (4.15, 6.54 and 9.05) and under all conditions (filtration or stirring) and pyrolysis temperature.Biochars also showed no effect on aflatoxins adsorption. Great differences were observed for the adsorption rates of OTA in function of the studied conditions. The adsorption efficiency of biochar for OTA increased with the increase of the pyrolysis temperature, which increases the specific surface area. The method used (filtration or stirring) had a strong influence on the adsorption rate, ranging from 29% by filtration up to 52% for 1000 mg of a biochar in 5 mL of water-methanol solution;and stirring increasedthe adsorption rate. In general, pH had less effect on the adsorption rate of OTA (2-5%). OTA best adsorption rate was observed for biochar produced at 800°C. The affinity between biochars and aflatoxins is very strong because atthe same experimental conditions and equal masses, biochars adsorb more aflatoxins than OTA (5 times more).

Governments and international instances are trying to improve the food safety system to prevent, reduce or avoid the increase of food borne diseases. This food risk is one of the major concerns for the humanity. The contamination by mycotoxins is a threat to the health and life of humans and animals. One of the most common mycotoxin contaminating feed and foodstuffs is ochratoxin A (OTA), which is a secondary metabolite, produced by Aspergillus and Penicillium strains. OTA has a chronic toxic effect and proved to be mutagenic, nephrotoxic, teratogenic, immunosuppressive, and carcinogenic. On the other side, because of their high stability, specificity, affinity, and their easy chemical synthesis, aptamerbased methods are applied to OTA biosensing as alternative to traditional analytical technique. In this work, five aptamers have been tested to confirm qualitatively and quantitatively their binding with OTA. In the same time, three different analytical methods were tested and compared based on their ability to detect and quantify the OTA. The best protocol that was established to quantify free OTA from linked OTA involved an ultrafiltration method in green coffee solution with. OTA was quantified by HPLC-FLD to calculate the binding percentage of all five aptamers. One aptamer (The most effective with 87% binding with OTA) has been selected to be our biorecognition element to study its electrical response (variation of electrical properties) in the presence of OTA in order to be able to make a pairing with Radio Frequency Identification (RFID). This device, which is characterised by its low cost, speed and a simple wireless information transmission, will implement the knowledge on the mycotoxins molecular sensors (aptamers), an electronic device that will link the information, the quantification and make it available to operators.

When Arabica coffee undergoes a wet process, the harvested cherries are depulped and the mucilage that is still surrounding the bean is removed by a step of biochemical reactions also called “fermentation”. Previous studies showed the impact of the inoculation of selected Saccharomyces cerevisiae yeast on coffee cup quality and a yeast strain-dependent effect was put into evidence. The aim of the present study was to evaluate two specific strains on different raw materials at pilot-scale and realize a scale-up of the treatments under industrial conditions. Pilot-scale experiments evaluated the selected yeasts that were inoculated during a fermentation step lasting either 12 or 36h in comparison with the spontaneous fermentation. The trials were repeated at industrial scale in order to evaluate the yeast inoculation impact at larger-scale (100 kg to 1 ton batches of depulped cherries) including several factors such as the maceration duration, the raw-material quality and maturity and the production area. The effect on the biochemical composition as well as volatile organic compounds (VOCs) of coffee was measured. Sensory analysis (SCAA method) was performed in order to determine the impact of yeast inoculation on cup quality. Whereas yeast didn't impact the global biochemical composition of the green coffee, the results of the volatile compounds analysis on the pilot-scale trials evidenced a higher amount of esters on the green coffee proceeding from the inoculated pulped coffee; and the sensory analysis revealed a yeast positive impact on coffee overall quality in particular for one of the studied yeast strain. The results from industrial-scale trials confirm the good performance of the selected yeast and its contribution to coffee overall quality.

The isomers of chlorogenic acids (CQAI), and other chemical compounds in green coffee beans, contribute on formation of complex sensorial attributes of coffee beverage. The aims of this study were to estimate the chemical composition, including CQAI, in green coffee beans collected from canopy vertical layers of Coffea arabica L. (cv. IAPAR 59) and to associate this composition to the sensorial attributes of coffee beverage.The plants were grown in two densities (6,000 and 10,000 plants ha-1), and twoplanting patterns (PP),square (Q) and rectangular (R), resulting in four combinations (Q6, Q10, R6 and R10).Two 40cm-thick layers in vertical profile of coffee canopy were considered (upper layer - Luand inferior layer - Li).The concentration of fats, proteins, sucrose, reducing sugars, phenolic compounds (PC), chlorogenic acids and caffeine in green coffee beans were performed by NIRS. The mass/volume ratio was considered as the green beans density. The following isomers: 3-caffeolquinic acid (3-CQA), 4-caffeolquinic acid(4-CQA), 5-caffeolquinic acid(5-CQA), 5-feruloylquinic acid (5-FQA), 3,5-dicaffeoylquinic acid (3,5-diCQA), 4,5-dicaffeoylquinic (4,5-diCQA) and 3,4-dicaffeoylquinicacid (3,4-diCQA) were determined by ultra fast liquid chromatography. Principal component analysis (PCA) was applied to associate the coffee beans physicochemical components to the plant density, planting patternsand canopy layers. The PCA was efficient to discriminate between two PPs, showing that beans originated from rectangular ones contented chemical composition that was associated to better beverage quality. The free-choice profile technique (FCP) was employed to estimate the sensorial attributes of coffee beverage. FCPindicated that the beverage from Liexpressedsweetness, bitterness, browncolorandlow astringency. In PCA those samples were related to high concentrations of 3,4-diCQA, sucrose, caffeine and proteins.The PCA and FCP analysis showed the influence of berry position on plant architecture. The berries maturated in the self-shaded layer (Li) had the chemical composition that resulted in more appropriated beverage attributes than those ones formed and maturated in sun-exposed (Lu) layer. In the second production year, the rectangular PPs originated berries with better chemical and sensory attributes.