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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: Free fatty acids (FFA) result from hydrolysis of cocoa butter triacylglycerides due to various abiotic and biotic factors. The resurgence of high FFA contents above 1.75% in cocoa beans depended on Ivorian geographical origin. High FFA contents have become a serious quality problem because they induced serious consequences for some beneficial properties of cocoa butter and chocolate. This study investigated the improvement of quality of Ivorian cocoa beans by reducing their FFA contents. Methodology: Samples: 240 cocoa beans batches were sampled from cocoa farmers of some big cocoa producing regions for their FFA contents analysis. Also, influence of primary post-harvest processing such as pod’s sanitary status, pod opening delay, fermentation duration and dry cocoa beans storage under various relative humidity (RH) ranged 80-90% on FFA’s formation of Ivorian cocoa beans was investigated. Data interpretations were performed according to the Fisher’s test. Results: Main results showed that dry cocoa beans recorded FFA content varying from 0.99 to 14% in function of the geographical origin. Beside, 53% of tested cocoa bean samples exhibited FFA content up to 1.75%. Poor sanitary status of pods and 7-days fermented cocoa beans recorded FFA content above 1.75%. Dry cocoa beans stored at RH above 85% promoted more the FFA’s formation (14%) than those stored under lower RH values. 53% of tested cocoa beans samples presented FFA contents up to 1.75%. Controlled primary post-harvest processing highlighted that poor sanitary status of pods, 7-days fermentation and storage of dry cocoa beans at RH above 85% lead to FFA content above 1.75%. Conclusion: So, in order to produce fermented and dried cocoa beans containing a suitable FFA content in the context of climate change, mitigation strategies need to integrate good crop conditions regarding postharvest processing and to improve beneficial ones.

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 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.

Roasting is an important process that could influence the quantity of butter extracted. Central Composite Design (CCD) approach was used to study the influence of the couple temperature/duration of roasting on the quantity of extracted butter. The roasting conditions used were temperatures in the range of 110–197 °C and time ranging from 10 to 57 min. A total of 13 couple was tested. The result highlight that roasting conditions significantly affected the quantity of obtained butter. The best couple temperature – duration were 125 °C/57 min and 140 °C/40 min with an extraction yield of about 25%. However, obtained cocoa butter presented a wide diversity with respect to texture, colour and odour characteristic. Physicochemical properties of extracted butter were not function to the roasting conditions. Iodine and saponification indices were within the norms. However, the humidity rates of the studied cocoa butter were largely above the standard rates. Findings of this research are useful to food industries, and the impact of cocoa roasting on the extracted butter properties could help developed new products. Keywords: Cocoa beans, Roasting conditions, Cocoa butter, Physicochemical properties, Sensorial properties

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.

To characterize the street food sector in Yaounde, an inventory of 197 culinary preparations available in its seven major markets was conducted. The main offerings included: boiled rice, wheat donuts, cassava sticks (Ebobolo), groundnut sauce, boiled plantains, corn donuts, fried beans, and fufu corn. The analysis of variances highlighted their variation in the markets, with the predominance of certain culinary dishes in one market relative to another. Two important aspects were looked into: geographical location and specialization in street food consumption. Then those markets were grouped into four homogeneous classes: [Essos, Acacia, and Mvog-Ada], [Etoudi and Nkolbisson], [Mokolo], and [Mvog-Mbi] markets. Markets belonging to the same class had high probability of having the same culinary preparations. Principal component analysis confirmed that Mvog-Ada and Acacia markets were the closest, as well as Nkolbisson and Etoudi markets. Yaounde’s markets culinary preparations, despite their diversi...

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

Every year, large quantities of husk resulting from the dry method of treatment of robusta coffee are dumped into nature. This generates multiple harmful ecological effects. The downward trend of coffee prices and the rise in the cost of manure has urged coffee farmers to better exploit the by-products of coffee transformation. Thus, a test for the mineralization of coffee husk to obtain soap factory raw material was carried out in the coffee – cocoa technology laboratory at Nkolbisson in Cameroon. To start and improve combustion, three types of fuel namely; cocoa husk, palm bunches and palm nut cake was used. After 16 h of combustion, the highest rate of mineralization was obtained with the palm nut cake (86%) followed by cocoa husk (55%) and the palm bunches (43.4%).This first result turns out to be interesting for further research.Key words: Coffee husk of coffee, mineralisation, fuel.

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 (

In order to fight malnutrition, functional cookies fortified with baobab pulp flour at partial substitution rates of 10, 20 and 30% were evaluated for consumer acceptability and nutritional quality. Consumer acceptability was evaluated in terms of taste, aroma, color and texture (hedonic characteristics) while nutritional quality was evaluated in terms of macro- and micro-nutrient compositions. Results showed that composite flours exhibited good functional properties. Twenty percent fortification cookies produced the most acceptable cookies which were rich in calories (490.24 kcal per 100 g), total fibre (8.65%), and total fat (27.52% DM). According to the National Agency of Sanitary Security recommendations concerning the contribution of each macromolecule to the total energy, crude protein intake was lower, polysaccharide intake was within the recommended value, while total fat intake was largely beyond that value. Mineral profile showed that cookies enriched with 20% of baobab pulp flour were rich in iron (15.6 mg/100 g), calcium (30 mg/100 g), magnesium (20 mg/100 g), potassium (930 mg/100 g), and vitamin C (60 mg/100 g). Thus, incorporation of baobab pulp flour at 20% improved sensory and nutritional qualities of rice cookies. Baobab fortified cookies can therefore be an alternative non costly and accessible snack to alleviate malnutrition in general and micronutrient deficiencies in particular. Keywords: Rice cookies, Baobab pulp flour, Nutritional properties, Sensorial quality

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).

The cultivation of plant such as cocoa, coffee and rice is practised by a large number of rural Cameroonian populations. Unfortunately, they are the most suffering of malnutrition, food insecurity and poverty. To improve their livelihoods, the Food Technology Laboratory (FTL) has developed some simple and innovative techniques to transform cocoa, coffee and rice and transferred them to producers. This study aims to evaluate the adoption of those innovations by producers. The survey was conducted in five most important markets in Yaoundé and in one pilot village named Bialanguéna. Data were analysed based on a comparison of the state before and after the acquisition of innovative technologies by producers. Changes observed in the food and economic habits were evaluated. The results show that cocoa products are the most adopted ones. Bialanguena women and Yaounde cocoa producers convert some cocoa beans to cocoa powder and cocoa butter for their therapeutic and nutritive needs. Yaounde cocoa producers go further to commercialize them and generate incomes. This is now their main source of financial income. Therefore, they can afford for food and housing of quality. These innovative technologies could be considered as an alternative to ensure food security in rural area. But the vulgarisation of technologies must continue to reach a large number of producers.