The seeds of baobab (Adansonia digitata L.) and the tubers of tigernut (Cyperus esculentus L.) were analysed chemically for their proximate composition and amino acids. The tubers contained 47.9% digestible carbohydrates, 32.8% oil and 3.8% crude protein. The baobab seeds contained 24.1 % digestible carbohydrate, 29.7% oil and 28.4% crude protein. A mixture of the vegetables was prepared from three parts of the tigernuts and one part of baobab seeds, by weight, such that a 10% crude protein meal was obtained. The chemical score of the mixed vegetable was 51%, based on limiting amino acids, i.e. those which contain sulphur. The level of antinutritive substances, such as tannin and tryptic inhibitors, in the raw vegetables were reduced by soaking or boiling.

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The effects of various processing techniques on nutrient composition and anti-nutritional factors in baobab seeds (Adansonia digitata L.) and locust beans (Parkia filicoidea L.) were investigated. The methods used for processing include boiling in water, acid or alkali and fermentation. Using the water treated samples as controls, there were slight decreases in protein and carbohydrate contents of the fermented and alkali-treated meals. However, an increase in extractable oil content was observed in acid, alkali and fermented samples. The alkali treatment appeared to be the most effective method for reducing trypsin inhibitor and tannin contents and has the additional advantage of improving the protein digestibility.

Six grain samples namely barley, maize, millet, rice, sorghum and wheat were tested for enzyme levels (amylase, protease and lipase) in order to assess their malting characteristics, using barley as a standard. The levels of the enzymes were estimated in the whole dry grains, 24h steeped, 24h sprouted and 48h sprouted grains. A combined statistical analysis of linear regression and analysis of variance were used to test for enzyme interaction, similarities and interspecific relationship between the cereals. The estimated interspecific relationship between sorghum and barley was 84% based on the three enzymes, while millet had 75%. All the sprouted cereals with the exception of the standard barley had high lipase levels. This possibly suggests certain limitations as regards to production of off-flavours. Malt prepared from maize, sorghum, rice and millet had comparable protease levels with barley (P>0.05). The malts prepared from maize, millet, rice, sorghum and wheat had comparatively low alpha-amylase levels when compared with the standard barley. Multiple linear regressions showed amylase was dependent on lipase and protease. The relationship was not affected by either soaking (steeping) or sprouting of the grains. The implications of these findings suggest that a combination of these cereals might give good malt for food applications.