Search

Chocolate is a “pleasure” food whose organoleptic quality is essential to the product's value. The aromatic quality of chocolate comes from many parameters, some are intrinsic to the raw material, and others are driven by the manufacturing process. In the frame of a research project dealing with the management of cocoa fermentation process, we investigated the impact of specific yeasts inoculation on the quality of cocoa beans after fermentation and on the final sensory quality of the chocolate Two different yeasts have been inoculated and fermentations were compared to a spontaneous fermentation (standard cocoa). Then, the beans were transformed into chocolate via a standard process and the sensory characterization of these samples was carried out. The analysis of the volatile fraction and the biochemical composition have also been done on beans and chocolate. The results of the beans fermented by selected yeasts show levels of sugars (sucrose, glucose and fructose) lower than in standard cocoa. The polyphenol contents are also impacted by depending on the fermentation process. The analysis of the volatile compounds were also performed on all fermented beans, and important differences were detected. Among the various chemical families measured, the alcohols and esters are more abundantly present in the fermentations carried out with the yeast starters. The sensory tests also confirm that the quality of these beans are also considered better. In conclusion, these studies confirmed the high interest to better control the fermentation step with specific yeast inoculation, in order to improve the final quality of chocolate.

PAH occurrence in raw cocoa and derivative products is more and more worrying for the health of chocolate consumers. Consequently, European Union has fixed PAH maximal content in cocoa products by EU Standards 835/2011 and 2015/1933. Present research dealt with the impact of post-harvest treatments on PAHs formation in raw cocoa.

In this deliverable the main results of sensory profile of reengineered products from group I are presented. Group I included Akpan and Gowé (Benin), Kenkey (Ghana) and Kishk Sa'eedi (Egypt). In this stage all products were submitted to reengineering process to overcome food safety and product quality issues (identified in the first stage of the project in traditional food) to facilitate their promotion and introduction to EU markets. Although all products were tested in Europe for consumer acceptance, in the case of SENSORY, for Kenkey and Akpan in Europe, the results although not obtained by a trained panel, were generated by Consumers through CATA test. The use of check-all-that-apply (CATA) questions for sensory product characterizations with consumers has been gaining acceptance by several authors (G. Ares and S.R. Jaeger, 2015) and for that we considered an equivalent test to replace the classical descriptive analysis by the trained panel that would take longer time. Due to the restrictions of delayed reengineering processes, we did not have an enough frame time to train adequately the panel. However, the characterisation of product attributes was also achieved. In the case of Gowe, due to restrictions in the productions of reengineered product due to contaminations of raw material, these results for sensory profile could not be obtained, but this was the only case in group I. However, the differences in main attributes were not so far from the traditional ones. In sensory studies of reengineered products, we´ve tried to integrate quantitative characterization of the perceivable product attributes and in consumer studies hedonic profiles (Worch, Lê, and Punter, 2010). So, in the sensory profiling of a specific group of reengineered products, once performed by a trained panel for a specific group of attributes by a specific African or European country panel, it must be considered unique and reproducible for all other panels that can test the product, afterwards. So in our sensory study of Kishk Sa'eedi as it was performed in Africa or Europe by a trained panel performing quantitative and reproducible characterization of the perceivable (Kishk Sa'eedi) attributes, herein will be used the same results for European sensory description of the product. Akpan: In terms of consumer perception of sensory attributes performed in Europe for the three Akpan products did not significantly. If we remove the terms such as “artificial”, “strong in taste”, “floral” due to a manufacturing error (use of a few drops of citronella essential oil instead of citronella infusion as a traditional flavouring of Akpan in Benin), it remains the terms “mealy”, “liquid” “drinking yoghurt” that better describe the product and were previously used for describing traditional Akpan product. This means that sensory properties of traditional Akpan were not totally improved during re-engineering to meet French consumer taste. Kenkey: The results of this study based on CATA testing allowed to provide a basis of understanding on how the reengineered Kenkey (RK) compares to standard commercial Kenkey (SK) in terms of its sensory properties. An interesting finding was that the sensory properties of RK were very different from that of the standard Ga Kenkey (SK): consumers scored differently the new product from the standard one. RK was globally perceived as too weak whilst SK was too strong. RK was perceived as bland and crumbly and SK as sour, salty and fermented. Kishk Sa'eedi (KS) was evaluated by a trained panel by QDA and analysed using QFD and PCA analysis. The results of KS sensory characteristics provide in depth understanding of the sensory quality criteria as perceived by the sensory trained panel. The present study showed that substantial differences in sensory character were noted between the traditional and re-engineered KS in particular, differences in colour, fresh odor, KS taste, fracutability and mouth coating. This work showed that the application of techniques could provide the useful information to KS and helped to identify the importance of product attributes. So in general, it can be observed that sensory properties of reengineered products of Akpan and Kenkey did not differed significantly from traditional ones, however the opposite was observed for the new KS compared to the traditional one.

This deliverable concerns the sensory evaluation of the reengineered group 1 African products in the AFTER project. Specifically, it related to reengineered akpan and gowe from Benin, kenkey from Ghana and Kishk Sa'eedi in Egypt. Concerning reengineered akpan from Benin, the sensory evaluation was undertaken in Montpellier, France. Re-engineering of akpan has focused primarily on improvement of sanitary properties of the product, which was a great achievement and will allow producing Akpan on a larger scale in SMEs in Africa. Sensory evaluation of the Akpan products was carried out using CATA and JAR techniques that have been developed for use with consumers instead of a trained panel. Three Akpan products were tested by 102 consumers: Akpan added with 10% sugar (AS10), Akpan added with 3% spray-dried milk and 8.7% sugar (AMS8.7) and Akpan added with 3% spray-dried milk and 15% sugar (AMS15). Independently of the Akpan tasted, Acidity or Sweetness attributes were scored “Just About Right, as I like” by 56 to 77% of consumers. Odour perception was perceived differently, depending on consumers. However, Texture was found “Too weak”, too liquid by the majority of consumers (49 to 55%) and Taste “too strong” (46 to 54%). The most frequently CATA descriptors checked by consumers which better described Akpan products were: “Artificial”, “Floral”, “New/Different”, “Strong in Taste”, “Mealy”, followed by “Liquid”, “Drinking yoghurt”, “Sweet”, “Acidic”, and “Rough”. At the opposite, an ideal-yoghurt was described as Creamy, Natural, Good for health, Refreshing, Homogeneous, with a texture of a Bulgarian yoghurt-type, Thick, Sweet, Attractive, Nutritious and Milk taste. In terms of sensory evaluation, the three Akpan products did not significantly. If we remove the terms such as “artificial”, “strong in taste”, “floral” due to a manufacturing error (use of a few drops of citronella essential oil instead of citronella infusion as a traditional flavouring of Akpan in Benin), it remains the terms “mealy”, “liquid” “drinking yoghurt” that better describe the product and were previously used for describing traditional Akpan product. This suggests that sensory properties of the reengineered Akpan may not be acceptable to French consumers who prefer a product with a creamy, homogeneous, Bulgarian yoghurt-type taste. Gowe in Benin was not tested using sensory evaluation. Sensory testing of Gowe in Benin was not undertaken because this was planned to be undertaken in Europe. The reason is because the methodology used in sensory evaluation is independent of the location provided the samples are the same. However, the particular samples provided for French sensory testing contained a concentration of aflatoxin that was higher than the minimum EU allowable limit. It was not possible to repeat the sensory test in France because it would have taken too long to obtain a replacement supply from Benin and to repeat the processing (takes one week). In which case the samples would have been took different to enable a comparison. The sensory evaluation of kenkey was carried at the Food Research Institute, Ghana. Current trends in urbanization, and the increasing popularity of kenkey among consumers, require larger scale production with consistent quality. Testing was conducted to determine the sensory profile of white reengineered kenkey made using the optimum pre-process conditions of steeping time (30 and 45h), steeping temperature (30ᵒC and 35ᵒC) and dough fermentation time of 12 hours. The qualitative descriptive analysis showed that the sensory profile of white kenkey was dependent on preprocessing variables. Thus merely optimizing the pre-processing variables with regards to acid production and other readily measurable constituents though could shorten the production process could not guarantee the best product sensory quality. The results show that all the descriptors generated were appropriate for differentiating sensory qualities among samples and could be used for basic research and product development for white kenkey. Soft and sticky texture in white kenkey was highly appreciated. Sensory evaluation of Kishk Sa'eedi (KS) was undertaken in Egypt. KS is an Egyptian indigenous wheat-based fermented food prepared traditionally according to the method applied by Upper Egyptians. This work is done to characterize sensory properties and sensory profile of the reengineered KS. Quantitative descriptive analysis (QDA) coupled with principal component analysis (PCA) was used to study the interrelationship among and between sensory attributes. 14 terms regarding appearance, odour, flavour and texture of the samples, was selected and a glossary describing each descriptor was developed. Three KS samples were profiled by 11 assessors using the chosen 14 sensory descriptors. Mean intensity ratings of the descriptive attributes showed that there were significant differences (p