Effect of Processing Techniques on Levels of Minerals and Antinutritional Factors of Canavalia ensiformis

Abstract

Proximate composition and effect of boiling, roasting and fermentation on mineral elements, Phytate, Oxalate, Tannin and Cyanide in Canavalia ensiformis seeds were evaluated. Raw sample was analyzed for proximate composition. The results show that the seed is high in protein and carbohydrates (23.53% and 53.57% respectively). Fermentation and vigorous roasting increased Calcium by 14.29% and 33.33% respectively. Phosphorus was increased by 0.8% with mild roasting. Potassium and Phosphorus are high in the raw sample. Two methods of roasting were employed namely: 1 hour roasting (mild roasting) and 3 hrs roasting (vigorous roasting). Mild roasting increased Phytate concentration (31%). Other processing methods significantly reduced antinutrient factors (p<0.05). Boiling and fermentation greatly reduced Tannin (93%and 92% respectively). Cyanide showed respective 87.5% and 88.4% reduction with boiling and fermentation. Mild roasting reduced oxalate to 0.8% from 5.9%. Combination of boiling and mild roasting will result in more reduction compared with single treatment in all the antinutrients factors studied. The seeds can effectively substitute for protein deficient food and feed for animal if the amino acids profile is studied.