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BACKGROUND: Consumers of boiled cassava in Africa, Latin America and Asia use specific preference criteria to evaluate its cooking quality, in terms of texture, colour and taste. To improve adoption rates of improved cassava varieties intended for consumption after boiling, these preference criteria need to be determined, quantified and integrated as post-harvest quality traits in the target product profile of boiled cassava, so that breeding programs may screen candidate varieties based on both agronomic traits and consumer preference traits. RESULTS: Surveys of various end-user groups identified seven priority quality attributes of boiled cassava covering root preparation, visual aspect, taste and texture. Three populations of contrasted cassava genotypes, from good-cooking to bad-cooking, in three countries (Uganda, Benin, Colombia) were then characterized according to these quality attributes by sensory quantitative descriptive analysis (QDA) and by standard instrumental methods. Consumers' preferences of the texture attributes mealiness and hardness were also determined. By analysis of correlations, the consumers' preferences scores were translated into thresholds of acceptability in terms of QDA scores, then in terms of instrumental measurements (water absorption during boiling and texture analysis). The thresholds of acceptability were used to identify among the Colombian and Benin populations promising genotypes for boiled cassava quality. CONCLUSION: This work demonstrates the steps of determining priority quality attributes for boiled cassava and establishing their corresponding quantitative thresholds of acceptability. The information can then be included in boiled cassava target product profiles used by cassava breeders, for better selection and adoption rates of new varieties.

Crop breeding in sub-Saharan Africa has made considerable gains; however, postharvest and food-related preferences have been overlooked, in addition to how these preferences vary by gender, social difference and context. This context is changing as participatory approaches using intersectional gender and place-based methods are beginning to inform how breeding programmes make decisions. This article presents an innovative methodology to inclusively and democratically prioritise food quality traits of root, tuber and banana crops based on engagement with food systems actors and transdisciplinary collaboration. The outcome of the methodology is the Gendered Food Product Profile (GFPP) – a list of prioritised food quality characteristics – to support breeders to make more socially inclusive decisions on the methods for trait characterisation to select genotypes closer to the needs of food system actors. This article reviews application of the methodology in 14 GFPPs, presents illustrative case studies and lessons learned. Key lessons are that the transdisciplinary structure and the key role of social scientists helped avoid reductionism, supported co-learning, and the creation of GFPPs that represented the diverse interests of food system actors, particularly women, in situ. The method partially addressed power dynamics in multidisciplinary decision making; however, effectiveness was dependent on equitable team relations and supportive institutions committed to valuing plural forms of knowledge. Actions to address power asymmetries that privilege particular types of knowledge and voices in decision making are crucial in techno-science projects, along with opportunities for co-learning and long-term collaboration and a transdisciplinary structure at higher level.

Recent developments with the CGIAR have led cassava variety development to increasingly focus on assessing clones based on end-user acceptance of the crop and of finished product(s). Consumer testing of boiled cassava was carried out in rural areas (Luweero and Apac) and urban areas (Kampala) of Uganda. Consumers were invited to test boiled products from several cassava varieties and give their opinion about the products using various methods including overall liking (9-point hedonic scale), Just-About-Right (JAR) and Check-All-That-Apply (CATA) tests. Using these methods, consumers indicated their preferred sensory attributes for boiled cassava. Results showed that consumers preferred local varieties Bao, Bwanjule and Nabwangu, which possessed good quality attributes namely; 'mealiness', 'sweetness', 'softness', 'nice aroma', 'whiteness', 'firmness' and 'sticky'. Newly improved varieties and Alanyo Deri- a local variety - were least preferred because boiled cassava product resulting had poor qualities such as; 'dry', 'bitterness', 'watery', 'hard', 'tastelessness', 'yellow', 'fibrous' and 'odourless'. This information gathered in this activity will be key for WP2 to determine appropriate physicochemical evaluations to assess cassava clones' qualities.

Cassava breeding programs in Uganda do not currently select materials based on flour making quality, explaining in part the low adoption rates of many released varieties. In this study, we describe end user trait preferences, processing qualities and physicochemical properties of cassava flour. We found that higher proportion of women than men showed preference for most attributes of cassava flour quality evaluated in this study. Preference for color was 66% and 52% among women and men, respectively, while that for stickiness of Kwon was 26% (women) and 15% (men). Ease of peeling and stickiness of Kwon were key processing traits. Heap fermented flour had higher pasting temperatures, but lower viscosities than sun‐dried flour, and had lower amylose content compared to fresh root starch. The results demonstrate the importance of gender sensitive participatory evaluation of breeding materials, in tandem with physicochemical evaluation during selection of best possible candidate breeding lines.

The sensory evaluation by trained panelists was conducted to establish a standard operating procedure (SOP) for routine undertaking of sensory evaluation to determine the quality of boiled cassava roots by by breeders to improve consumer acceptability of new varieties. Accordingly, we worked with the trained panellists to come up with a list of descriptors that could be used to assess the quality of boiled cassava roots. In total, 21 descriptors associated with appearance, texture, taste and aroma of boiled roots were determined. Having learnt from consumer-testing and surveys, there was need to establish standard descriptors that can be routinely used by sensory panelists to assess quality attributes during varietal development process by breeders. To this end, roots from different clones were harvested and prepared for cooking in a food science laboratory. After cooking, one clone was served to the panelist at a time, and requested to evaluate the sample based on their prior knowledge regarding appearance and texture both in mouth and touch; taste and aroma were also assessed. The panelists were given plain paper to write descriptors, after which a discussion was held with all panelists and the team facilitating the activity. The panelists were requested to highlight the key terminologies they had used to evaluate the attributes of cooked cassava. The highlighted descriptors were written on flip charts that were pinned on the wall of the training room so that everybody could easily follow the discussion. The highlighted descriptors were carefully grouped into categories such as texture by hand, aroma, appearance, taste, and texture by mouth. In the end, after a series of discussions and evaluating a number of cassava clones, a catalogue of 21 descriptors for boiled cassava was developed.

At NaCRRI, activity four, a component of WP1, involved participatory processing of boiled cassava; this hinged on Step 2 that focused on gendered food mapping. Accordingly, key processing operations important for quality boiled cassava were identified by processors resident in Apac and Luweero districts in Uganda. Survey results indicated that the main processing steps were: peeling, trimming and steaming. However, there were variations in processing roots after trimming. For example, while sliced cassava roots in Luweero were wrapped in banana leaves and steamed, in Apac, sliced roots were immersed in water and boiled. Some consumers in Apac pounded boiled cassava slices into a mash. No significant differences in yield were observed amongst cassava genotypes. Nonetheless, some varieties like “Alanyo dyer” and “Nase 13” which were susceptible to CBSD, had low yield after processing. End-user attributes preferred during processing cassava roots in Apac were: white flesh colour, ease of peeling and a firm root; least preferred attributes included hard to peel, spongy in the middle, and roots which do not cook easily. On the other hand, preferred attributes in Luweero included: easy to peel, white flesh colour, no fibres on the surface of peeled root, a non-lignified/woody ('telina ekitti'), no bitter taste, smooth root surface, and a firm flesh; undesirable attributes included: lignified/woody root and spongy in the middle. This information was consequently incorporated into the consumer questionnaire that was used for Step 4.

Recent developments with the CGIAR have led cassava variety development to increasingly focus on assessing clones based on end-user acceptance of the crop and of finished product(s). Consumer testing of boiled cassava was carried out in rural areas (Luweero and Apac) and urban areas (Kampala) of Uganda. Consumers were invited to test boiled products from several cassava varieties and give their opinion about the products using various methods including overall liking (9-point hedonic scale), Just-About-Right (JAR) and Check-All-That-Apply (CATA) tests. Using these methods, consumers indicated their preferred sensory attributes for boiled cassava. Results showed that consumers preferred local varieties Bao, Bwanjule and Nabwangu, which possessed good quality attributes namely; 'mealiness', 'sweetness', 'softness', 'nice aroma', 'whiteness', 'firmness' and 'sticky'. Newly improved varieties and Alanyo Deri- a local variety - were least preferred because boiled cassava product resulting had poor qualities such as; 'dry', 'bitterness', 'watery', 'hard', 'tastelessness', 'yellow', 'fibrous' and 'odourless'. This information gathered in this activity will be key for WP2 to determine appropriate physicochemical evaluations to assess cassava clones' qualities.

The sensory evaluation by trained panelists was conducted to establish a standard operating procedure (SOP) for routine undertaking of sensory evaluation to determine the quality of boiled cassava roots by by breeders to improve consumer acceptability of new varieties. Accordingly, we worked with the trained panellists to come up with a list of descriptors that could be used to assess the quality of boiled cassava roots. In total, 21 descriptors associated with appearance, texture, taste and aroma of boiled roots were determined. Having learnt from consumer-testing and surveys, there was need to establish standard descriptors that can be routinely used by sensory panelists to assess quality attributes during varietal development process by breeders. To this end, roots from different clones were harvested and prepared for cooking in a food science laboratory. After cooking, one clone was served to the panelist at a time, and requested to evaluate the sample based on their prior knowledge regarding appearance and texture both in mouth and touch; taste and aroma were also assessed. The panelists were given plain paper to write descriptors, after which a discussion was held with all panelists and the team facilitating the activity. The panelists were requested to highlight the key terminologies they had used to evaluate the attributes of cooked cassava. The highlighted descriptors were written on flip charts that were pinned on the wall of the training room so that everybody could easily follow the discussion. The highlighted descriptors were carefully grouped into categories such as texture by hand, aroma, appearance, taste, and texture by mouth. In the end, after a series of discussions and evaluating a number of cassava clones, a catalogue of 21 descriptors for boiled cassava was developed.

At NaCRRI, activity four, a component of WP1, involved participatory processing of boiled cassava; this hinged on Step 2 that focused on gendered food mapping. Accordingly, key processing operations important for quality boiled cassava were identified by processors resident in Apac and Luweero districts in Uganda. Survey results indicated that the main processing steps were: peeling, trimming and steaming. However, there were variations in processing roots after trimming. For example, while sliced cassava roots in Luweero were wrapped in banana leaves and steamed, in Apac, sliced roots were immersed in water and boiled. Some consumers in Apac pounded boiled cassava slices into a mash. No significant differences in yield were observed amongst cassava genotypes. Nonetheless, some varieties like “Alanyo dyer” and “Nase 13” which were susceptible to CBSD, had low yield after processing. End-user attributes preferred during processing cassava roots in Apac were: white flesh colour, ease of peeling and a firm root; least preferred attributes included hard to peel, spongy in the middle, and roots which do not cook easily. On the other hand, preferred attributes in Luweero included: easy to peel, white flesh colour, no fibres on the surface of peeled root, a non-lignified/woody ('telina ekitti'), no bitter taste, smooth root surface, and a firm flesh; undesirable attributes included: lignified/woody root and spongy in the middle. This information was consequently incorporated into the consumer questionnaire that was used for Step 4.