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Kenkey, is a maize based sour, stiff dumpling, and it is among the most common fermented cereal food products in Ghana. There are several types of kenkey, and while some are made from whole maize grains others are produced using degermed/and dehulled maize grains. The kenkey types made using dehulled maize grains are less popular and have largely remained at the level of “ethnic food”, restricted to very few socio-cultural communities. Current trends in urbanization, and the increasing popularity of kenkey among consumers, require larger scale production with consistent quality. The study was carried out to examine the traditional white kenkey process and to optimize the key processing variables in order to obtain reproducible quality white kenkey that will be acceptable to native and non-native consumers. A survey was conducted in three white kenkey production districts to collate information on production, vending and consumption practices. The sensory profile and consumer acceptance of different types of kenkey and other fermented maize products in Ghana were investigated. A total of two hundred consumers including 110 Ghanaians and 90 internationals were used for the consumer test. Traditional white kenkey types were analyzed for their physicochemical, textural, microstructure and sensory characteristics. Physicochemical analysis involved determination of pH, titratable acidity, sugars, lactic acids, minerals, vitamins and amino acids using high performance liquid chromatography procedures. The textural characteristics of white kenkey randomly obtained from traditional processors were determined using instrumental (texture analyser) and consumer assessments. The effects of processing variables of steeping time (12, 30 and 48 h) and dough fermentation time (0, 12 and 24 h) on the physicochemical properties of white kenkey were determined. A (three variable) Box-Behnken design was used to optimize the processing variables of steeping time, steeping temperature, and fermentation time on white kenkey quality parameters of moisture, pH, titratable acidity, glucose and lactic acid content. The optimum region of the process variables was obtained by hedonic tests on the white kenkey using balanced incomplete block design (for k= 5, b= 21, λ=2, r =7) Quantitative Descriptive Analysis (QDA) was conducted on white kenkey made from within and outside the optimum region of the process variables, as well as white kenkey obtained from vendors using a panel of 18 trained members. Consumer acceptance study was conducted using 65 consumers for white kenkey obtained from the optimum region and traditionally processed white kenkey obtained from vendors. The results of the survey showed that there were two main types of white kenkey, nonsweetened white kenkey and sweetened white kenkey to which sugar is added during production. All three procedures involved steeping of dehulled maize grains which is then milled into a meal. In the (procedure at Atimpoku), the meal was not fermented any further but precooked, moulded into balls wrapped in leaves and steamed. In the (procedure at Anum), the meal was kneaded into dough and allowed to ferment for 12hours, the fermented dough (70%) is precooked and mixed with the remaining dough, moulded into balls and steamed. Three classes of behaviours of consumers were identified. Those who liked all the products 'all likers' (36%), those who preferred the white kenkey 'white likers' (30%) and those who preferred Banku 'banku likers' (34%). Sensory attributes important for the white likers were whitish colour, fruity odour, smooth and nonsticky texture, a less sour product without a pronounced fermented odour, and a bland taste. The white kenkey samples randomly obtained from vendors contained 70 – 77 % moisture, 0.58-0.88 g/100 g ash, 0.09-0.19 g/100 g fat, 2.45-2.84 g/100 g protein, vitamin B1 of 17-47 g/100 g, had pH of 4.07 –4.54, titratable acidity 0.42-0.60% lactic acid, 2-28 mg/g glucose, and 0.6-2 mg/g lactic acid. The amino acids lysine, methionine, Gaba and Ornitine values were less than 0.2 g/100g. Steeping time of maize was complimentary to fermentation time since both influenced the conversion of glucose by lactic acid bacteria into lactic acid. Generally, the longer steeping and fermentation times gave higher levels of glucose and lactic acid in the white kenkey. However, whilst steeping increased glucose level, dough fermentation reduced it. The intensity of whiteness (L) in white kenkey diminished as steeping time increased. On the other hand, fermentation time improved whiteness of kenkey. High aflata (i.e ratio of precooked to uncooked dough) produced kenkey with softer texture, whilst reducing the aflata ratio increased the hardness and stickiness of white kenkey. Consumers preferred white kenkey made using high aflata ratio and steamed for longer periods. The optimization studies showed that processing variables had significant effects on the physicochemical and sensory characteristics of white kenkey. The optimum region for the process variables at which the most acceptable kenkey was obtained were steeping time of 30-45 h at 30-35ºC temperature followed by 12 h dough fermentation. Consumer acceptance test indicated no significant difference in acceptance between the traditionally processed white kenkey samples and those obtained from the optimum region. White kenkey samples of higher quality potential has been identified. The process for production of white kenkey has been standardized, saving production time.

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

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.