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Uapaca kirkiana ('Masuku') and Strychnos cocculoides ('Kabeza') juices and jams as well as juices from Adansonia digitata (Baobab, 'Malambe') and Mangifera indica (mango) were prepared, evaluated by a trained ten-member panel (seven women and three men) and analysed for their physicochemical and shelf-life characteristics. The physicochemical data indicated that juices and jams are rich sources of zinc, copper and phosphorus. While sensory evaluations of the jams were not significantly different between Uapaca and Strychnos fruits (P > 0.05), significant differences were, however, obtained for the juices, with Strychnos juice being the more preferred. Compared with Baobab and mango juices, Strychnos juice, unlike Uapaca juice, exhibited relatively low fungal, yeast and bacterial contamination. Thus, processing and handling of the products were hygienically undertaken. Therefore, both Uapaca and Strychnos fruits have adequate potential for food product development, and their products are rich sources of trace elements (Zn and Cu).

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The physicochemical properties of native Malawian cocoyam starches vary among the different accessions and differ from those of cassava and corn starches.

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Cassava roots contain cyanogenic glucosides. Malawian farmers classify cultivars into two groups based on the perceived danger of eating raw roots that they associate with bitterness. In the vernacular, cultivars that produce roots with bitter taste are called vyakubaba (bitter), whereas those yielding non-bitter roots are called vyakuzizra (cool). In the scientific literature they are distinguished as 'bitter' or 'sweet'. Roots from 'bitter' cultivars are processed prior to consumption. We studied the ability of farmers to predict the cyanogenic glucoside levels of 492 roots from the 10 most commonly grown cultivars. Twenty-eight farmers predicted the taste of each of the cultivars that they grew, and scored bitterness on a five-point scale by tasting the root tip. Thereafter cyanogenic glucosides were determined on half of the root, while a taste panel scored the taste of the other half. The mean cyanogenic glucoside level in 132 roots from 'cool' cultivars was 29 mg HCN eq kg −1 fresh weight (CI 25-33, range 1-123) and in 360 roots from 'bitter' cultivars was 153 mg HCN eq kg −1 fresh weight (CI 143-163, range 22-661). Farmers' distinction of 'cool' and 'bitter' cultivars predicts glucoside levels. The tasting of the tip of the root improved the farmers' prediction of toxicity. Scoring of bitterness by a trained taste panel showed a stronger correlation with glucoside levels (r 2 = 0.67). This suggests that cyanogenic glucosides confer the bitter taste, notwithstanding the probability of additional modifying intrinsic factors.