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White fonio (Digitaria exilis) and California blackeye cowpea (Vigna unguiculata) flours were used in sugar cookie preparation. Formulations were: (1) 100% wheat, (2) 50% wheat/50% fonio, (3) 50% wheat/50% cowpea, (4) 33% wheat/33% fonio/33% cowpea, (5) 25% wheat/75% fonio, (6) 25% wheat/50% fonio/25% cowpea, (7) 75% fonio/25% cowpea and (8) 50% fonio/50% cowpea. The 100% wheat cookies had the greatest spread ratio (5.86) and the 75% wheat/25% cowpea the least (4.39). The 50% fonio/50% cowpea cookies required the most force (720.3 N) to shear and the 50% wheat/50% fonio the least (399.4 N). The 100% wheat and the 50% wheat/50% cowpea cookies had the lightest colour and the 25% wheat/75% fonio the darkest. Sensory panel assessments of appearance, colour and texture were not affected by component flours. Cookies containing 100% wheat or 50% wheat /50% fonio received the highest hedonic ratings for flavour (7.1 and 6.7, respectively) and overall acceptability (6.9 and 6.5, respectively). All other formulations were unacceptable.

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The efficiency of decorticating cowpeas was improved by hydrating to 25%, then drying to -10% moisture. Effects of drying temperature (SO", 70°, 90", llO", and 13O'C) on functional and nutritional properties of cowpea meal were assessed. Extraction rate (yield) was unaffected by heating. Average particle size and water absorption of meal were greatest for intermediate temperatures. Starch was not gelatinized at any temperature. Reduction in protein solubility, which occurred at temperature 2 9O"C, was associated with changes in gel electrophoresis patterns. Protein solubility was negatively correlated with previously reported values for specific gravity and apparent viscosity of cowpea pastes. Increases in drying temperature reduced thiamin content and increased browning of the meal.

Cereal Chem. 77(2):213-219Cowpeas (Vigna unguiculata) were milled through 0.5-, 1.0-, and 2.0mm screens, and the flour was subsequently separated into different particle-size ranges. Such procedures caused only minimal changes in moisture, fat, protein, ash, and total carbohydrate. The amount of extractable starch, however, varied from 34.5 to 52%. The effects of both mill screen and sieve mesh size were significant (P < 0.05). Differences in milling and separation procedures resulted in significant variations in water absorption (0.41-2.81 g of water/g of flour), solids lost (0.34-1.17 g/g of flour), and protein solubility (21.2-37.4%) (P < 0.05). Finely milled flours (91% moisture) had lower initial gelatinization temperatures (70-73°C), as measured by differential scanning calorimetry (DSC) (P < 0.01). Gelatinization peaks in high-moisture flour were similar to that of pure starch. At lower moisture, a second peak was observed indicative of protein. Light-scattering analysis showed that different conditions produced a bimodal particle-size distribution when samples were suspended in water. The small size had relatively constant diameters (19-21 µm) and was associated with starch granules. The latter had a large size distribution and varying peak size and was associated with aggregated flour particles. These results indicate that changes in processing produces cowpea flours with differing chemical and physical properties.

Functional properties of cowpea flour as affected by soaking, soaking/boiling (S/B), and fermentation of seeds with Rhizopus microsporus subsp. oligosporus before milling were investigated. Soaking and fungal fermentation had less influence on functionality of flour compared to S/B, which markedly decreased solubility and impaired emulsifying properties. Solubility of heat-denatured proteins was slightly improved by fermentation. High emulsion capacity was not associated with high emulsion viscosity or solubility. The combined effects of heat treatment and fungal fermentation on equilibrium moisture content were apparent at 75−97% equilibrium relative humidity. Cowpea flours were consistently more hydrophilic than lipophilic, regardless of processing treatment. The least gelation capacity of flours increased as a result of heat treatment. Keywords: Cowpea flour; Vigna unguiculata; functional properties; soaking; heat treatment; fungal fermentation; Rhizopus microsporus subsp. Oligosporus

The relationship between seven types of food safety concerns and the corresponding change in food consumption habits of 236 households in Georgia, USA was evaluated. Results showed a gap between food safety concerns and food consumption habits. Gaps were particularly evident in the cases of pesticide residues, animal drug residues, growth hormones and bacteria. For example, more than 54% of sample households were extremely concerned about pesticide residues, but only 35% actually took extreme precaution in buying items considering this perceived threat. The study indicated that educating consumers about preventive methods to reduce food safety threats will lead to reduced concerns and changes in food consumption habits.

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