ABSTRACT
Food nutrients such as carbohydrates, fats, proteins and vitamins are essential for growth and development of man. Cocoyam (Colocasia esculenta), family: Araceae, is a common tropical root crop cultivated in many parts of the world for food formulation and consumption by man. This study was conducted to asses various aspects of nutritive value and storage chemical changes in cocoyam and soya bean flours and their various blends.
The sun-dried samples were milled to size (sieve with 25µm aperture size) to obtain homogenous flours. Blends were obtained with various ratios according to the percentage of soybean/cocoyam flours (10% (10g: 90g), 20% (20:80), 30 %( 30:70), 40 %( 40:60), 50% (50:50). The proximate compositions (moisture, crude protein, crude fat, ash, crude fibre and nitrogen-free extract) were determined using standard methods. Qualitative and quantitative phytochemical screenings were evaluated while mineral elements (Na and K) were determined by flame photometry method and Mg, Ca, Fe, Zn and Cu by atomic absorption spectrophotometry (AAS) method. Amino acid and fatty acid profiles were determined using gas chromatography (GC), while vitamins were determined using high performance liquid chromatography (HPLC). Nutritional evaluation of the various food products were done by animal feeding trials, which involved protein efficiency ratio (PER), net protein retention (NPR), weight gain and biological value (BV). In addition, storage changes in the samples at different water activities of 0.11, 0.33 and 0.75, were monitored.
