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The seeds of lesser-known species - Cucumeropsis mannii, Lagenaria sicceraria varieties 1 and 2 and Telfairia occidentalis, of Cucurbitaceae family were studied. The protein content of C. mannii was 36.1% and the varieties 1 and 2 of L. sicceraria had 32.1% and 33.3% respectively. Telfairia occidentalis had protein content of 33.2%. The fat contents of C. mannii, L. Sicceraria var. 1 and 2 and T. occidentalis were 44.4%, 44.6%, 46.9% and 42.3% respectively. The crude fibre content for each of the two varieties of L. sicceraria was 3.6% and T. occidentalis had 5.5%. Cucumeropsis mannii had the lowest (2.4%) fibre content. The carbohydrate contents for L. Sicceraria var. 2, C. mannii, and T. occidentalis were 12.6%, 13.2% and 14.4% respectively. Lagenaria sicceraria var. 1 had the highest value of carbohydrate (15.8%). The species were relatively rich in potassium and magnesium with range of values of 0.56% to 0.68% and 434 ppm to 444 ppm respectively. Cucumeropsis mannii and Lagenaria sicceraria var. 2 had relatively high contents of calcium (117 ppm) and iron (109 ppm) respectively. The kernels of these species exhibited lipase activity. Telfairia occidentalis showed the highest degree of lipase activity.

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Summary The kinetics of the thermal degradation of thiamine in periwinkle‐in‐brine (PIB), periwinkle‐in‐sauce (PIS) and periwinkle‐in‐egusi soup (PES) were investigated in the temperature range 104–121.1 °C (5–40 min). Thiamine degradation could be modeled as a first order rate reaction with the rates being higher in the brine than the formulated food systems. The temperature dependence of the rates of destruction gave highly significant correlations when analyzed by the thermal resistance, Arrhenius and absolute reaction rate methods. Ea‐values ranged from 107.2 kJ mol–1 in PES to 111.5 KJ mol–1 in PIB. The ΔH# and ΔS# values ranged from 103.9 kJ mol–1 and 52.4 J deg–1 mol–1 respectively in PES to 108.3 kJ mol–1 and –40.5 J deg–1 mol–1 respectively in PIB while the z‐values were 26.3, 25.5 and 25.3 °C for PES, PIS and PIB respectively.

The physicochemical properties of fractionated maize flour and the textural characteristics of a maize-based nonfermented food gel (maize tuwo) prepared from the respective fractionated flours were evaluated. The maize flour was fractionated into four fractions: <75 lm, 75-150 lm, 150-300 lm, 300-425 lm and whole meal (<425 lm). There were variations in the selected chemical constituents of fractionated maize flour including protein (2.9-4%), ash (0.80-0.97%), crude fibre (0.73-0.91%) and damaged starch (10.1-17.4%). The fractionated maize flour gave variable bulk density (0.80-0.93 g cm )3 ), water absorption capacity (1.9-2.1 g g )1 ) and oil absorption capacity (1.7-2.1 g g )1 ). The colour characteristics of the fractionated maize flour and the pasting properties were all affected by the fractionation. The cohesiveness index (strain at peak compressive force) of the food gel from the flour fractions ranged between 15% and 19.5% while the softness index of the food gel ranged between 16.7 and 17.5 mm. The relative high cohesiveness and softness indexes (i.e. 19.5% and 17.4 mm respectively) of maize tuwo prepared from the flour fraction of 75-150 lm can predispose the food gel towards easier hand-mouldability and swallowability respectively; being important quality indicators for its acceptability.

The flour from cassava tubers contains about 2.5 % of lipids, of which only half is extractable with conventional solvent systems. Extractable lipids are mainly polar in character, the principal group of components being galactosyl diglycerides. A new galactolipid, tetragalactosyl diglyceride, is described for the first time. The component fatty acids are relatively saturated in character in comparison with those of other structural lipids, such as those of the potato.

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Aspergillus flavus, Aspergillus fumigatus, Aspergillus niger, Helminthosporium oxysporium, and Penicillium frequestans isolated from common Nigerian agricultural residues like cassava, yam, banana, and plantain peels and brewery spent grains (BSG) were screened for their ability to produce β-amylase and amyloglucosidase using submerged and solid-state cultivation regimens. Enzyme activity (EU) was determined by estimating the amount of reducing sugars produced as a result of the action of crude enzyme solutions on buffered starch solution. Results showed that A. niger liberated the highest level of β-amylase (33.2 EU) on plantain peels medium using the static cultivation method, while it produced the highest amount of amyloglucosidase (29.8 EU) on yam peels substrate with solid-state cultivation regimen. Plantain peels favored β-amylase production more than the other tested wastes supporting production of 33.2 and 9.8 EU of the enzyme in A. niger under solid-state and static cultivation methods, respectively. Yam peels favored liberation of 15.3 EU amyloglucosidase in each of the solid-state and the static cultivation regimens. Production of β-amylase on BSG, yam, banana, and plantain peels was not significantly facilitated by static cultivation method (p>0.05), while solid-state cultivation regimen favored amyloglucosidase production on cassava peels and BSG (p<0.05). Optimal production yield of β-amylase and amyloglucosidase were 16.6 and 14.9 EU g −1 on plantain and yam waste media by the mold.