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Akpan is a traditional ready-to-drink fermented yoghurt-like cereal beverage consumed in urban and rural areas in Benin. With the aim of adapting the product to new local and export markets, this work maps African and European consumer preferences for different types of Akpan. RESULTS A sensory profile of Akpan was created and consumer tests were conducted with 103 consumers of African origin and 74 consumers of European origin. Consumer acceptance was significantly correlated with fermented odour (r = −0.94) and milky taste (r = 0.92–0.97) attributes. Cluster analysis revealed different behaviour by African and European consumers with respect to acceptability of Akpan; European consumers did not like the sour taste and African consumers liked an intense sweet milky taste. CONCLUSION This study provides information on how Akpan, and other fermented yoghurt-type cereal products, could be adapted to African and European consumer preferences. © 2014 Society of Chemical Industry.

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

In this deliverable, the reengineered products relating to groups 1 to 3 are tested by consumers in Africa in order to test whether the acceptance meets consumer needs. The summaries are by group. These products were widely different and tested in differing cultures and situations. A common feature, however, is that all products are already commonly consumed by the communities and accepted, particularly with respect to the baseline products. Some products were found to be more acceptable (Gowe and Akpan in Benin, Kenkey in Ghana, Kong and Lanhouin in Senegal, Bissap and Baobab in Senegal), some of similar acceptance (Kitoza in Madagascar) and some were less acceptable (Kishk Sa'eedi in Egypt and Jaabi in Cameroon). Ways forward are discussed in all cases. Group 1: The reengineered group 1 products had mixed acceptance to consumers. Ones that were highly accepted were the reengineered Akpan which was highly accepted regardless of age, gender, socio- professional category and possessions (goods) and the majority (84.9%) expressed an interest for purchasing the reengineered Akpan and the reengineered gowe (n=100 consumers) in Benin, which was strongly accepted and more so than the traditional gowe. However, the reengineered Kenkey in Ghana while being comparable acceptance to the traditional white kenkey this would only meet a niche market. However, for the reengineered Kishk Sa'eedi, it was less acceptable and the difference was due to sour taste and spicy flavour. Group 2:The group 2 products had mixed acceptance among consumers. In the case of Kong in and Lanhouin in Senegal, the reengineered products had improved acceptance while for kitoza in Madagascar, there was no improvement in acceptance apart from those in terms of quality and safety. More specifically, Kong made using liquid smoke novel technique (RLK) had by far the highest acceptance and could easily be integrated as part of the Senegalese cuisine. This shows that there is a potential for RLK on the Senegalese market. Two types of reengineered Lanhouin types (Lanhouin dry powder, Lanhouin dry fillet) were greatly acceptable and the powdered form more than the fillet. In the case of Kitoza, consumer acceptance studies showed that there was no significant difference between all samples tested. Group 3: Group 3 reengineered products had mixed acceptance among consumers. Re-engineered bissap (hibiscus drinks) in Senegal were positively appreciated by consumers in Senegal and better accepted than the traditional commercial infusion used as baseline comparison. However, the new drinks were not perceivably different from the baseline drink to consumers concerning both the traditional character and the nutritional and healthy attributes. The reengineered baobab drinks were positively appreciated by consumers in Senegal and significantly better appreciated than the traditional commercial ones earlier tested. Jaabi (Ziziphus mauritiana). The result is the proposition of a reengineered Yaabande presenting fine texture well appreciated by consumers. However, particle size was critical and this needed to be lower than 125μm. Due to this limit, processors have adopted the manual production of flour of particle size 250μm>Ø>125μm, which is less tiresome, though it appears in second rank in the preference of consumers. The detailed methodology for each product is given for Groups I, II and III respectively. Common to all of the methodologies is the Ethical assessment and consent which is listed as follows: Ethical assessment and consent. The studies have been assessed and approved by the University of Greenwich Research Ethics Committee and the Ethics Committee at CIRAD. Consent was sought from sensory panellists and from adult consumers participating in this study. Enumerators informed participants about the study and explained that their participation was entirely voluntary, that they could stop the interview at any point and that the responses would be anonymous.

Objectif : Evaluer trois équipements pour la fermentation de la pâte destinée à préparer l'ablo (pâte cuite à la vapeur) puis, l'influence de la température, de la durée de fermentation et du taux de levure ajoutée à la pâte. Méthodologie et résultats : La pâte semi-solide a été fermentée durant quatre heures à température ambiante (26-27 °C) dans du bac en verre, glacière et bassine en aluminium (Témoin). En outre, l'effet de la température, de la durée de fermentation et du taux de levure a été évalué à travers un dispositif factoriel complet dont les niveaux bas et hauts des facteurs rangeaient entre 2 et 6 heures, 22 et 30 °C et 1 et 3 g/Kg de farine. La pousse, le pH, l'acidité titrable et la charge en levures/moisissures ont été déterminés. A l'exception de la quantité de mousse produite et de la matière sèche, aucun effet significatif (P>0,05) du matériel de fermentation n'a été mis en évidence sur les paramètres mesurés. Le taux de levure, la température et la durée de fermentation avaient une influence positive significative (P

The sensory profile and consumer acceptance of a traditional flavouring agent and taste enhancer (FATE) locally referred to as Lanhouin, which is a salted fermented fish product made from two types of fish (king fish and cassava fish) through three different fermentation processes (aerobic, semi-aerobic and anaerobic conditions) were explored. The sensory testing was performed by 17 semi-trained panellists, and the acceptability of FATE was tested by consumers (n=200) in Cotonou and Abomey-Calavi municipalities. Traditional FATE were sensorially different, with king fish FATE having the strongest odour (ammoniacal odour) and cassava fish FATE being whitish in colour. Three classes of consumer behaviour were identified; primarily those who liked all the FATE samples (35% of consumers); those disliking FATE made from anaerobically fermented king fish (37%); and those disliking FATE made from aerobically fermented cassava fish (28%). Consumer acceptance was significantly associated with fish size, whitish colour, dried fish odour and ammoniacal odour. In terms of consumer preference, FATE made from semi-aerobically fermented king fish and FATE made from cassava fish (except for aerobic fermentation) were the most preferred and would be the most suited for further product development suited to markets in West Africa and export to the EU. The similarity in taste attributes for cassava fish and king fish when used for cooked rice dishes will be helpful in designing the form in which FATE can be marketed for wide acceptance.

French consumer acceptability of Akpan, a traditional Beninse yoghurt-like product, was carried out in Montpellier, France. A sort of “All in one” method was used comprising an hedonic scoring (appearance, odour, taste, texture and overall liking using a 9-point scale, but also sweetness and acidity using a JAR scale), a Check-All-That-Apply (CATA) question with 25 sensory and 6 perceptions descriptors, and a questionnaire on the views about the product with some socio-demographic information. Four Akpan products were tested by 104 consumers: Natural Akpan AN, and Natural Akpan added with three ingredients (sugar AS; condensed milk AM; condensed milk and sugar AMS). The overall acceptability of Akpan products significantly differed. Only Akpans added with sugar were on average acceptance (mean score around 5-6) but found too sweet by most of consumers. The two others, with no sugar added, were the least liked, with a mean score lower than 5. Acidity was perceived differently by the consumers depending of the products and their sensibility. Three groups of consumers were identified: the Akpan dislikers (25%), the sweet Akpan likers (32%) and Natural Akpan dislikers (44%). Through a MFA analysis of CATA results, AN was described as tasteless, watery, mealy, sour, with fermented taste, pasty consistency, neutral odour and was associated to bitter, astringent and rough perceptions. AMS was related to cereal and yoghurt taste, creamy consistency, milk odour, smooth appearance and to nutritious perception. AS was related to Bulgarian yoghurt appearance, citrus or floral taste and odour, homogenous consistency and, to artificial perception. AM was related to compact appearance, cereal and fermented odour, milk taste, and to natural perception. Sensory terms were found close to perception terms in MFA plan and both were highly correlated to overall acceptance. Most of the consumers disliked by the Akpan products and would not buy them (86%). For the least liked product, 44% of consumers would like to change everything except colour. For the most liked product, 37% would like to change odour, taste and texture. 42% thought that Akpan could not replace any product they know well and 36% thought that it could replace soy yoghurt. 30% of the respondents could buy this product for intolerance to dairies and pleasure and 60% for all the reasons except pleasure and diet.

Concerning re-engineering, based on deliverables from WP1 (D1.1.2.1-survey results, D1.2.4.1-results for sensory, physical and textural analysis) and WP5 (D5.1.2.1- marketing and regulatory opportunities, D 5.3.2.1 – sensory and consumer tests), a first diagnostic of product opportunities, processing problems and re-engineering options has been obtained for each product (gowé, akpan, kenkey and Kishk Sa'eedi “KS”). The main objectives and actions that will be followed for re-engineering are listed in Annexes. First results concerning re-engineering are then presented, followed by a plan of work for each product The main conclusions for reengineering options are as follows: (a) re-engineering will with in particular deal improving shelf life and sanitary level of the traditional products. This will go through controlling fermentation by using in particular specific functional inoculums combined with re-engineering of the other unit operations (malting, milling pre-cooking, etc) that interfere with fermentation control. (b) Several options of re-engineering will be targeted: improvement of the “homemade” processes and traditional products, involving low capital investment processes and few modifications of the form of the original products that are targeted to the local market, and deeper process modifications and new formulations and ways of presentations of the products for larger processors and national and international markets; this includes in particular ready to prepare dried Akpan, Gowé and kenkey and new ready to drink/eat products (for all products).

The sensory profiles and acceptability of Akpan, Gowe, Akpan and Kishk Sa'eedi were tested using a focus group discussion, a quantitative descriptive panel and consumer panels comprising African and/or European consumers as indicated in the table below. It should be noted that consumer testing of Kishk Sa'eedi was delayed because of the current social unrest in Egypt. The number of consumers interviewed by product and country is summarised in the table below. Consumer Class (and number): Country Benin Product Akpan African: 103Non-African74 Country Ghana Product Kenkey African: 110 Non-African90 Country Benin Product Gowe African: 141Non-African- Country Egypt Product Kishk Sa' eedi : African- Non-African- Sensory testing indicated that for each product, the sensory profiles widely differed. This was influenced by the raw material (Kenkey, Gowe, Akpan, KS), process (Kenkey, Akpan and KS) and addition of sugar/milk (Akpan and Gowe). The products also differed according to acceptance. Akpan - African and non-African consumers behaved differently with respect to acceptability. Europeans generally had a lower acceptability of Akpan products compared to Africans. This was probably due to the fact that most Europeans were not familiar with the product since when Europeans did report consuming Akpan, there were no differences in acceptability. Consumers' acceptance was significantly associated with fermented odour and milky taste. African consumers were more sensitive to the thick/concentrated texture and cereal taste whilst Europeans were more positively influenced by sweet taste but negatively by acidic taste. Kenkey – African and non-African consumers differed in acceptance of Kenkey. Non- African consumers mostly preferred the white kenkey and to a lesser extent banku. Ghanaian consumers generally liked all of the samples or preferred banku. Sensory attributes important for the white likers were whitish colour, fruity odour, smooth and non-sticky texture, a less sour product without a pronounced fermented odour, and a bland taste. Salty taste correlated significantly with acceptance for the banku likers, Gowe - The commonly consumed gowe were sensorially distinct products with differences between the sorghum and maize samples of gowe, but no significant difference was noted with sugar was added. Regarding consumer testing, three distinct patterns of consumer acceptability were observed, which were grouped as 'Sugary Gowe likers' or “Natural sorghum Gowe dislikers” (63.1%) followed by 'Sugary sorghum Gowe likers' (20.6%) and 'Indifferent Gowe likers' (16.3%). Saccharified malted and no-malted sorghum Gowe without sugar were the least preferred. Kishk Sa'eedi (KS) has distinct sensory attributes and variation. Consumer acceptance has still to be completed. The conclusions for reengineering are as follows: Akpan – there are two options being products suited to a) Akpan from Maize Ogi containing Sugar and Milk (OMsm) or b) Akpan from Ogi Sorghum containing Sugar and Milk (OSsm). However, since they are representative of classes of akpan type, any of these two classes could be suited for the reengineering. That is the case of OMs or OSs membership of OMsm and OSsm respectively. Kenkey - Two products should be considered, one adapted to both the European and the Ghanaian consumer 'white likers' and the second adapted to only the Ghanaian consumer 'all likers and 'banku likers'. Important sensory attributes which should guide re-engineering of the first product are whitish colour, fruity odour, smooth and nonsticky texture, a mildly sour product, and a bland taste. This may be achieved by a combination of processing factors including dehulling of maize kernels, use of mixed lactic acid bacteria/yeast starter culture containing high concentration of yeasts cells (for fruity odour), reduced fermentation period (to reduce sourness and fermented odour) and elimination of the aflata step (to reduce sticky texture). The second product should be a refinement of Ga/Fanti Kenkey and should also focus on improved packaging. Gowe - Gowe made from saccharified malted sorghum with sugar (SSaSFs) was the most accepted and appears to be the most promising for reengineering. KS – the consumer testing will take place later in 2012 These findings should be considered in combination with other AFTER deliverables relating to market and regulatory issues and technical feasibility.

The sensory profile and consumer acceptance of Lanhouin, a traditional salted fermented fish made from two types of fish (king fish and cassava fish) and three different fermentation processes (aerobic, semi aerobic and anaerobic condition) were explored. Traditional Lanhouin were sensorially different, with king fish Lanhouin having the highest smell (score of putrid odour) and cassava fish Lanhouin being the whitish. Three classes of consumers' behaviour essentially, those who like all the Lanhouin samples (Lanhouin likers; 35 % of consumers), those who does not prefer king fish Lanhouin from anaerobic fermentation (Lanhouin KFAN dislikers; 37 %) and those who does not like cassava fish Lanhouin from aerobic fermentation (Lanhouin CFA dislikers; 28 %) were identified. Consumers' acceptance was significantly associated with size of fish, whitish colour, dried fish odour and ammoniacal odour. Considering consumers' preference, Lanhouin from king fish with semi aerobic fermentation and Lanhouin from cassava fish (except for aerobic fermentation) were more accepted and could be interesting for reengineering. The similarity in tasting attributes for cassava fish and king fish when used for cooked rice will be helpful to design the form in which Lanhouin can be marketed for large acceptance Considering Kong, no prior work has explored sensory tasting. Four samples were produced for the sensory test: Kong was smoked with wood only and or with wood/coconut. For the sensory evaluation, smoked kong only and smoked kong in sauce and were scored by a semitrained sensory panel. Then, 109 consumers were interviewed. Acceptability was only evaluated on smoked kong. The results show that all four samples were quite distinctive from each other but not when in sauce. Most of the Kong products were on average acceptable but moist kong had a better acceptability than dried kong samples submitted to the same processes of smoking. Consumers were segmented into two three groups as: “indifferent likers” (27%), “dry kong dislikers” (15%), and “dry Kong less preferred” (59%). Clusters really differed in terms of professional activity in fish sector but did not significantly differ in the frequency of consumption. Therefore it appears that, smoked Kong is a main product of consumption in the Senegalese market. Since more than 50% of consumers consumed smoked Kong at least once a week, it appears that Kong is a main product of consumption with a strong potential for the Senegalese market but also for the international market.

Sensory evaluation and consumer testing of Hibiscus, Baobab and Jaabi (Yaabande) was undertaken with African and EU consumers in Senegal and Cameroon. The sensory profile and consumer acceptance of Bissap (Hibiscus sabdariffa L.) drink (commercial and traditional) made from infusions of red calices of either local or Sudanese origin, pure or mixed, and either as syrup or a juice (infusion) was explored. There were significant correlations between the sensory perceptions of the drink by panellists. The acceptability of the drink was tested by two consumer groups: Europeans (n=60) and Africans (n=100) in Dakar. Three classes of behaviour from the consumers were identified. There were a) those who preferred syrup (syrup likers; 43% of consumers) b) those who prefer juices (juice likers; 36% of consumers) and c) those who preferred all of the samples (indifferent likers; 21% of consumers). The liking by African and EU consumers was similar but European consumers were more likely to prefer syrup, consume bissap the least often and purchase bissap juice in bottles. African consumers were more likely to prefer juice, consume bissap more frequently and purchase it in sachets. Both groups preferred to purchase natural bissap drinks rather than ones with added flavour. The sensory characteristics important to each class of consumers differed. There were significant correlations between acceptability, bissap taste for the cluster of the group of the juice likers. There were significant correlations between acceptability, sweet taste, acidic taste for the syrup likers. The study shows that the distinctions between the acceptability groups are very clear from a sensory perspective. The market study should take these preference groups into account when launching Hibiscus drinks on a new market. The sensory profile of seven samples of bouye (baobab) drinks (syrup and juice) was evaluated by 17 panellists. Consumer testing was investigated at four different locations in Dakar using the central location metho. These were the following: ESP high school (n=32); Grand Yoff (n=36), Guediawaye (n=12), and Gueule Tapée (n=26) areas. The acceptability of the drink was tested by African consumers (mainly Senegalese) (n=104) in Dakar who tested five different drinks from the seven first samples. A cluster analysis demonstrated that consumers behave differently with respect to acceptability. Three classes of behaviour from the consumers were identified. There were a) those who clearly preferred the juice from FWS (27% of consumers) b) those who preferred all of the samples (indifferent likers) (31% of consumers), c) those who liked the juices but not the syrups (juice likers) (42% of consumers). With respect to acceptance, the reengineering approach appears to have two options being products suited to a) milk taste or b) taste and odour characteristic of baobab with a good concentration for the two products. The reengineering approach should also explore ways to increase the shelf life with optimum quality regarding the sensory attributes and consumer acceptance. Optimizing scales for pasteurization shall be conducted in order to have a product without caramel smell. Sensory profile and consumer acceptability was undertaken for Jaabi, a wild fruit commonly used in savannah region of Africa, and its processed product, a cake locally called: Yaabande. The study took in the northern part of Cameroon through collection of two varieties of Jaabi (Dakamji and Lamouji) from four origins (Garoua, Maroua, Mokolo, Mora), and processed Yaabande from these samples, using three baking techniques (Sun baking, vapour cooking, under earth stewing). Sensory and consumers tests indicated that the taste of the products constitutes the main criteria for consuming the products. The Dakamji variety of Jaabi appeared more homogenous whatever the origin than the Lamouji variety. Meanwhile, all samples were acceptable at comparable level corresponding to pleasant character. With respect to acceptance, the main option of reengineering approach is based on standardisation of process procedures in order to guarantee the taste of the products. Inclusion of therapeutic aspects of the products may be coupled to this option for market development.

The evolution of cyanide content and colour were monitored during the processing of lafu, traditional flour and improved flour from five cassava cultivars from Benin. In addition, the total phenol, polyphenoloxidase (PPO), peroxydase (POD) and linamarase activities were assessed. The processing of cassava in lafu and improved flour proved superior for producing safe and white non-fermented and fermented cassava flours with total cyanide mean values of 16.6 and 11.4 mg HCN/kg, db and DE values of 9.2 and 12.1, respectively. Detoxification appeared to be only linked to processing, in particular to the size reduction level of cassava roots, regardless of the initial cyanide level and the linamarase activity of the fresh roots. Cassava flour yellowness was closely linked to the phenol content (r = 0.95) that decreased after steeping and pressing. The PPO and POD activities did not appear to be linked to flour discoloration.

Afin de tester l'effet du format sur la qualité (couleur et texture) des produits dérivés, des cossettes d'igname (Dioscorea rotundata-cayenensis, cultivars deba et gnidou) de différentes tailles (bâtonnets de 5 mm de diamètre, rondelles de 10 mm d'épaisseur et coupe traditionnelle; tubercule entier ou en grosses tranches L = 28cm; Ø = 2,6 cm) ont été soumises à une pré-cuisson dans l'eau à 65°C pendant respectivement 10 min, 20 min et 45 min puis séchées en étuve à 40°C pendant 1-5 jours. Les produits les plus clairs ont été obtenus avec les bâtonnets qui, réduits en farines, ont un indice de brunissement de 16,3 (cv. deba) et 16,1 (cv. gnidou) contre 19,3 et 24,6 pour les farines correspondantes issues des coupes traditionnelles. Parallèlement, la teneur en phénols totaux, principaux responsables du brunissement, est plus faible dans les farines de bâtonnets que dans les farines de coupes traditionnelles (en moyenne 1,6 [mu]M/g MS contre 2,2 [mu]M/g MS). En revanche, l'activité de la polyphénoloxydase, une des enzymes impliquées dans le mécanisme de brunissement, bien que fortement réduite au cours de la pré-cuisson, reste cependant plus élevée dans les farines issues des bâtonnets. En cours de cuisson, ces farines présentent par ailleurs des valeurs de viscosité et de gonflement plus élevées que pour les autres formats.

Les travaux précédents ont établi que l'indice de brun de l'amala est tributaire des phénols totaux de la farine des cassettes et de l'activité de la peroxydase du tubercule frais. Afin d'affiner ces relations, cette étude a été entreprise pour tenter d'identifier les composés phénoliques responsables et préciser leur évolution et celle des activités enzymatiques au cours du procédé de fabrication. Ainsi, les extraits phénoliques ont été analysés par la Chromatographie en Phase Liquide (HPLC). Leur évolution et celles des activités polyphénoloxydasiques (PPO), et peroxydasiques (POD) ont été suivi pour des blanchiments à différentes températures (60, 65, 70 et 75°C) pour deux variétés, Deba (D. rotundata) et Florido (D. alata). Florido possède une activité PPO initiale significativement plus élevée que Deba. Mais pour les deux variétés, l'activité de la PPO décroît progressivement au cours du blanchiment ; l'activité résiduelle est proche de 50 % après 50 mn à 60°C ou 65°C contre moins de 20 % à 70 ou 75°C L'énergie d'inactivation calculée est similaire pour les deux variétés (180 KJ Mot1) Par ailleurs, la POD est très rapidement inactivée, dès les 5 premières minutes du blanchiment, quelle que soit la température de traitement. Les phénols totaux diminuent durant le blanchiment jusqu'à 40 % du taux initial, indépendamment de la température. Les extraits phénoliques se composent essentiellement de flavanols et de composés cinnamiques. Parmi la quinzaine de composés séparés par HPLC, 3 ou 4 composés · majeurs représentent près de 50 % de l'aire des flavanols et plus de 70 % de celle des composés cinnamiques. La catéchine (flavanol) et l'acide férulique (acide cinnamique) font partie des composés majeurs. L'indice de brun de l'amala est lié à l'aire du pic détecté à 17 min pour l'igname fraîche. Ce pic serait ainsi l'un des précurseurs des corps bruns de l'amala. Une régression multiple révèle par ailleurs que l'aire des pics observés à 9 min et à 28 min dans la farine des cassettes expliquent plus de 86 % de la variabilité de l'indice de brun de l'amala.

La couleur et la texture sont deux attributs majeurs de qualité de l'amala, pâte obtenue à partir de la farine des cossettes d'igname. Ces attributs varient d'une production à l'autre. Afin d'évaluer l'effet de la variété et du procédé sur la qualité des farines de cossettes d'igname, des échantillons ont été préparées à partir de huit (8) cultivars en faisant varier les paramètres technologiques tels que les conditions d'épluchage et de découpage des tubercules, les conditions de blanchiment et de séchage. Le blanchiment réduit de façon significative l'activité de la peroxydase (POO) à 20 % de sa valeur initiale et celle de la polyphénoloxydase (PPO) à environ 50 % de l'activité initiale. Le trempage après blanchiment contribue aussi à baisser l'activité de la PPO. En outre, le séchage a considérablement fait chuter l'activité de la PPO et a accru la teneur en phénols totaux et l'indice de brun de la pâte amala. L'indice de brun de l'amala apparaît lié, d'une part, à la teneur en phénols totaux de la farine (r=0.84) et d'autre part, à l'activité initiale de la POO du tubercule frais (r=0,75). Le brunissement serait ainsi lié à une oxydation enzymatique (POO) des phénols durant la première phase de transformation (épluchage, début blanchiment) puis à une oxydation chimique et/ou enzymatique (PPO) durant le séchage.Le séchage a également fait chuter les viscosités des suspensions des farines ce qui serait lié à un phénomène de recuit de l'amidon qui diminue la capacité de gonflement à 95°C et la solubilité de la farine au cours de la cuisson. Par ailleurs, le découpage des tubercules (en bâtonnets ou en disque) a raccourci la durée de séchage et a entraîné une réduction de l'indice de brun et une augmentation de la viscosité des suspensions. Ceci peut être lié à une réduction des phénomènes d'oxydation des phénols et de récuit de l'amidon du fait de la réduction du temps de séchage.

La couleur, la texture et le goût sont les principaux attributs de qualité recherchés par les consommateurs d'amala. Cette étude a été entreprise afin de mieux préciser cette demande, de la quantifier par des méthodes instrumentales et d'en déterminer l'origine physico-chimique. Les résultats obtenus serviront d'outils pour l'étude du procédé. Plus d'une vingtaine d'échantillons de cossettes a été fabriquée avec des conditions expérimentales variées de manière à obtenir des échantillons d'attributs de qualité très diversifié.:;. Les amalas préparés à partir des farines de cossettes ont ensuite été testés par un panel de dégustation tandis que parallèlement des mesures instrumentales de texture et couleur ont été réalisées. Les résultats obtenus ont été mis en relation avec les mesures physico-chimiques obtenus sur les farines. Cinq caractéristiques gustatives principales ont été identifiées par le panel : les caractères sucré, amer, acide, fermenté et grillé. Les teneurs en certains composés comme le glucose et fructose, le lactate et les phénols totaux permettent de prédire de manière satisfaisante ces attributs de qualité : l'amertume apparaît en particulier liée à la présence de phénols. Parallèlement, les phénols sont aussi les premiers déterminants de l'indice de brun de l'amala. Trois groupes d'attributs sont mis en évidence concernant la texture de l'amala : les caractères lisse/grumeleux et lourd, élastique et collant, ferme et humide. Les caractères élastique et collant apparaissent en particulier fortement et positivement corrélés : l'attribut "élastique" représente plus un aspect filant de la pâte, propriété fonctionnelle proche du collant. Collant et fermeté peuvent être prédits par une mesure de résistance à la compression ou à l'extrusion. Cette dernière méthodologie, plus facile à mettre en oeuvre, sera privilégiée dans la suite de l'étude.

Samples of dried yam and yam flour obtained from local markets were analysed. Market yam flour and dried tubers had similar proximate composition except that the crude fibre content of the flour was lower. The ratio of load of rupture of dried yam tubers was 180-1630 kg/kg, indicating the resistance of the product to crushing. The yam flour was very fine. There was significant difference in colour between yam flour and amala, a paste made from it. Amala is a whitish to dark brown, elastic, soft, non-sticky, faintly bitter and faintly sweet paste.

Une grande variabilité est observée dans la qualité des mais cultivés au Bénin, et en particulier en ce qui concerne leurs caractéristiques physiques: les variétés locales ont des petits grains à tendance farineuse et tendre tandis que les cultivars améliorés ont plutôt des gros grains vitreux et peu friables. Ces caractéristiques vont conditionner leur aptitude à la transformation; les grains durs sont adaptés aux technologies faisant appel au dégermage (production de gritz de brasserie ou de mawè) tandis que les grains tendres seront facilement transformés en farine complète (lifin) ou en ogui. Un test de friabilité, mis au point au laboratoire, s'avère être un bon descripteur de la qualité technologique et culinaire du mais. Par ailleurs, une calibration selon la méthode en spectroscopie en proche infrarouge pour la détermination des caractéristiques chimiques et physiques des grains de mais entier a été mise au point au CIRAD. Elle permet de prédire l'ensemble des caractéristiques du grain en moins d'une minute avec une précision proche de celle des méthodes classiques tout en préservant intact l'échantillon. Elle peut ainsi être utilisée dans les schémas de sélection précoce sur un grand nombre d'échantillons.

The modifications occurring during the fermentation (at 20 or 35°C) and drying (under the sun or in an oven at 40°C) of maize flour (ogi) and cassava starch along with their expansion ability during baking were characterised and compared. A high temperature accelerated the fermentation but favoured lactic acid synthesis for maize ogi and butyric acid for cassava starch. The increase in acidity was higher for maize, but dried maize ogi did not evidence any expansion ability whatever the experimental conditions. Cassava starch that had been fermented at 20°C then sun-dried presented the highest expansion ability. It was associated with low paste viscosities and high swelling and solubilisation values. When the fermentation was carried out at 35°C, an annealing of cassava starch occurred that delayed starch gelatinisation and which could be involved in its lower baking expansion ability.

L'igname est un aliment très apprécié en Afrique de l'Ouest mais sa consommation sous forme de tubercules frais présente, pour les consommateurs urbains, de fortes contraintes. Celles-ci sont liées aux caractères saisonnier et périssable du produit qui rendent irrégulière sa disponibilité sur les marchés urbains. Avec l'urbanisation, on observe dans certains pays, le développement d'une filière originale de cossettes d'igname. Il s'agit d'un produit stabilisé obtenu à partir de petits tubercules épluchés, précuits et séchés au soleil. Pour mieux estimer l'importance et comprendre le fonctionnement de cette filière encore mal connue, une enquête de consommation sur les produits à base d'igname a été menée en milieu urbain dans trois pays : Bénin, Nigeria, Togo. Les consommateurs expliquent leur consommation de produits dérivés des cossettes par leur qualité gustative, leur constante disponibilité, leur facilité de préparation et leur prix accessible