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The potential uses of starches and flours depend on their physicochemical and functional properties. The chemical composition, functional and pasting properties of starch and flours obtained from some newly developed yam varieties from the Crops Research Institute (CRI), Ghana were evaluated, and compared with the existing local varieties. The results showed that the physicochemical and functional properties varied among the varieties studied. The CRI varieties were grouped in a principal component analysis as moisture (afase pa), amylose content (ahodenfo, soanyinto, afase biri), high starch content, bulk density and water absorption capacity (kukrupa, Mankrong pona, CRI pona). Starch pasting characteristics showed that Mankrong pona, CRI pona and afase pa exhibited stable pastes whereas afase biri, Mankrong pona and, afase soanyinto could be utilized for high-temperature processing. Overall, the new CRI varieties showed considerable functionalities that could be explored for potential food and industrial applications as compared to the existing local varieties.

The texture of yams is a key determinant in the selection of yams for boiled and pounded yams. This study was conducted to quantify pectin from local and newly developed yam varieties and to correlate pectin and its degree of esterification (DE) with instrumental textural profile parameters of boiled and pounded yam. Isolation of pectin from yam cell wall material (CWM) was achieved with citric acid and the degree of esterification (DE) was determined. The textural parameters were obtained using a texture analyzer. All the new D. rotundata (Poir) varieties had low CWM which varied from 11.88 to 18.95% compared to the D. alata varieties which ranged from 27.60 to 32.79%. Pectin yield (%) for CRI D. alata varieties ranged from 4.47 to 11.35 while CRI D. rotundata (Poir) varieties ranged from 5.18 to 5.50%. Generally, CRI D. alata yam varieties had higher pectin than D. rotundata (Poir) varieties. The DE for all samples ranged from 22.54 to 51.37%, making yam pectin low methoxy. Positive correlations existed between the textural parameters and pectin content as well as the DE but were not significant (p > .05). This study shows that low methoxy yam pectin has no effect on textural characteristics of boiled and pounded yam.

Gender-disaggregated sensory evaluation has become an essential element that could enhance breeding activities by increasing the adoption of new varieties. The effect of age, sex and geographical location on descriptor preferences for boiled and pounded yam were studied using descriptive and consumer testing. Attributes with definitions and measurement scales were used to generate lexicons for boiled and pounded yam. Analytical tools employed for the inferential statistics were the independent t-test, analysis of variance, Kruskal–Wallis test, Mann–Whitney test and relative importance index (RII). Descriptive testing showed that all the D. rotundata varieties were good for boiling and pounding. The D. alata varieties afase soanyinto and afase biri were most liked, while afase pa and ahodenfo were disliked. Age had no significant effect on descriptor preferences. Being a female or male, however, influenced preferences for pounded yam descriptors such as mouldability, lumpiness and colour. The RII for the D. rotundata varieties (0.22–0.28) showed that they are all good varieties for boiling and pounding. The local D. alata varieties were still highly acceptable compared the new CRI varieties due to the aroma. Rural consumers preferred all the descriptors of boiled D. rotundata than urban consumers, whereas urban consumers liked the pounded yam varieties better than the rural consumers. Availability of the new yam varieties on local markets could therefore increase consumption and improve adoption.