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Cameroon faces the serious challenge of postharvest losses which is partially due to mycotoxins contamination. In Cameroon, maize is one of the most vulnerable foods to mold contamination, whereas cocoa and coffee are food commodities with high impact on the economy when contaminated. Due to their potential negative impact on health (Mutagenic, hepatotoxic, nephrotoxic, haematotoxic, immunosuppressive, neurotoxic…), norms on the level of mycotoxins in marketed and consumed foods have been established worldwide. Currently, Cameroon does not have national standards or regulatory limits for mycotoxins in food and feed. However, in the absence of national law on mycotoxins, national regulations and initiatives (National Committee of Codex Alimentarius and Food Safety, Legal and regulatory framework of food quality control, Framework Law on Food Safety in Cameroon…) are taken by the government to protect the population. The food safety system in Cameroon involves several institutions and decentralized local authorities, thereby creating other jurisdictional conflicts (legal and organizational component.), which could negatively impact expected results. However, application texts and other specific texts are still awaited for better efficiency of the food safety system in Cameroon.

The objective of this study is to take an inventory of all the sachet water brands sold in Yaounde and to assess their sanitary quality. This study was carried out on 100 samples, representing 20 sachet water brands sold in the urban city of Yaounde, Cameroon. Selected physico-chemical and bacteriological analyses of the sachet water were done. The results showed that their pH values and nitrate level were in line with the WHO guideline values. The chloride ion contents were significantly lower than the limit values for drinking water, Escherichia coli was absent in all brands and 75% of the samples contained intestinal enterococci. Sachet water brands can be grouped into 3 homogeneous classes based on streptococcal contamination, chloride and nitrate content, and the level of pH. Packaging material and storage conditions (exposure to sun) can aggravate this contamination. Sachet water can be contaminated and become undrinkable. Key words: Sachet water quality, potability, Yaounde, Cameroon, physico-chemical parameters, bacteriological analyses.

The identification and use of natural compounds with antimicrobial activity against foodborne pathogens is of major importance. This study quantified, using Liquid Chromatography coupled with Mass Spectrum (LC‐MS), scopoletin in the roots of 20 cassava varieties that had been subjected to different commonly applied postharvest treatments to obtain local cassava‐derived foods. The extracted scopoletins were later characterized for their activity against Aspergillus flavus and Aspergillus niger, some food spoilage fungi. All studied cassava varieties contained scopoletin, with the improved varieties accumulating more of the compound. The compound was also present in all parts of the cassava root, but highest in the root flesh. Traditional processing influenced scopoletin content in derived foods with the chips having the highest content, followed by Gari and then Fufu. Scopoletin from cassava skin better inhibited mycelium growth of studied fungi. The Minimal Inhibitory Concentration ranged between 0.07 ± 0.00 µg/ml and 0.15 ± 0.00 µg/ml. PRACTICAL APPLICATIONS: This study paves the way for the valorization of cassava peelings in the conservation of several foods because of its antifungal activity.

Cyanide is a toxic substance found in several plants roots amongst which cassava. The objectives of this study were to quantify cyanide contents in the roots of the main cassava varieties cultivated in Cameroon and evaluate the effect of some traditional cassava processing methods on their initial contents. Ten local and ten improved varieties of cassava samples were collected in the locality of Mbankomo, Ongot village, Centre region. These roots were processed into traditional foods: “Chips”, “Gari” and “Fufu”. The cyanide content was determined in the parenchyma, cortex, and cassava derived foods. Local varieties had cyanide contents varying from 79.34±3.58 to 181.33±0.48 ppm, while contents in improved varieties varied from 61.03±9.44 to 118.04±7.16 ppm. Cyanide content quantitative classification revealed that studied cassava varieties fell within the range “moderately” to “highly” toxic. Results showed no clear link between morphological characteristic and cyanide contents of the studied cassava varieties. Although cyanide contents were higher in the cortex varying from 117.80±11.32 to 210.07±9.15 ppm for local, and from 98.43±15.49 to 155.44±12.11 ppm for improved varieties. Processing of cassava into different traditional foods contributed to reduce cyanide content. Elimination rates were as a function of the process involved: 47%, 80% and 91%, respectively, for “Chips”, “Gari” and “Fufu”. Cassava processing reduce cyanide content, however extent of reduction varies from one product to another. Keywords: Cyanide, Cassava cultivars, Traditional processing, Detoxification

Ochratoxin A (OTA) is a mycotoxin that contaminates several foodstuffs, including cocoa. It has nephrotoxic, teratogenic and carcinogenic properties in humans. The effect of post-harvest processing and storage on the OTA contamination of cocoa was studied over three successive cocoa seasons (2005, 2006 and 2007) in Cameroon. The type of fermentation (box or heap) did not significantly influence bean OTA content, which varied from undetectable (

Operating conditions affect ochratoxin A (OTA) extraction from roasted coffee. The OTA content found in the beverage can thus be greater than that found in the roasted coffee used to prepare it. Three extraction parameters were studied for roasted coffee: type of extraction solvent (alkaline, neutral, acid), temperature (ambient temperature/23 degrees C, 60 degrees C and 85 degrees C), and extraction time (5, 20, 30, 40, 50, 60 and 80 min). The alkaline solvent used in the method recommended by the European Union extracted OTA better, but a maximum content was obtained at 60 degrees C after 50 min. At least a 100% improvement in extraction was obtained when compared with the European Union usual quantification method that is carried out at ambient temperature. It turned out that the OTA extraction parameters for roasted coffee, as defined by that method, were not optimum and needed to be modified. These results were verified in double-extraction experiments showing that OTA is not completely extracted by this method. Confirmation was obtained by comparison of extraction methods on several commercial samples of roasted coffee.

Ochratoxin-A (OTA) is a mycotoxin that has nephrotoxic, tetragenic, immunotoxic and carcinogenic effects in the human organism. It contaminates several foodstuffs, notably cocoa. The purpose of our study was to compare the incidence of cocoa pod integrity on the fungal microflora and ochratoxin- A production in Cameroon. Irrespective of pod condition, fermented cocoa beans were contaminated by OTA. The maximum mould content was obtained in beans from damaged pod. However, the fungal microflora was more diversified for beans from pod damaged during harvesting than for beans from intact pods, throughout the post-harvest process. The toxigenic strains isolated belonged to the genera Aspergillus. Aspergillus carbonarius isolated from damaged pods, displayed the greatest OTA production which was 110.7 ng.g-1 on cocoa medium and 2772,0 ng.g-1 on official medium. There was a good correlation between OTA presence in the beans and isolated toxigenic strains.

Ochratoxin A (OTA) is the main mycotoxin occurring in cocoa. A study was conducted in Cameroon to assess how filamentous fungi and toxigenesis were affected by the type of cocoa post-harvest treatment (boxes or heaps). The filamentous fungi isolated were almost identical when fermentation was carried out in boxes or heaps, with the presence of abundant black Aspergillus filamentous fungi: A. niger and A. carbonarius. Filamentous fungi were more abundant at the end of the harvesting season. Factors affecting bean integrity (poor handling, deferred processing) resulted in a qualitative and quantitative increase in contamination, when the total number of filamentous fungi could reach a maximum value of 5.5+/-1.4x10(7) CFU g(-1) and black Aspergilli a maximum value of 1.42+/-2.2x10(7) CFU g(-1). A toxigenesis study showed that Aspergillus carbonarius was the main OTA-producing strain isolated. Its maximum production could reach 2.77 microg g(-1) on rice medium. Aspergillus niger strains did not always produce OTA and their toxigenesis was much lower. Fermented dried cocoa from poor quality pods was the most contaminated by OTA: up to 48 ng g(-1).