ABSTRACT

The effects of heat processing on the proximate composition and energy value of the seed kernel flours of African walnut (AW) used as traditional snacks in most parts of Nigeria were investigated. In this research, moisture, ash. crude fibre and carbohydrate contents decreased during heating while crude protein and crude fat generally increased. The increase or decrease in these values was not significant at the S% level. For instance, ash decreased from 6.05 + 1 .71% in sample A (Raw African walnut) to 5.45 ± 0.86% in sample D (135mm cooked African walnut). Crude fat was highest in sample B (45n1in cooked African walnut) with the value 52.8 + 2.70% followed by sample C (90mins cooked African walnut) with the value 51.7 ± 1.610/0 and was lowest in sample A (Raw African walnut) with the value 49.8 ± I .OS%. while calorific/energy value was lighest in sample B (45mm cooked African walnut) with the value 612.2 + 11.7% followed by sample C (90rnins cooked African walnut) with the value 609.3 ± 6.23% and lowest in sample A (Raw African walnut) with the value 593.4 + 6.75%. The functional characteristics investigated were Water absorption capacity. Oil absorption capacity. Foaming capacity, Emulsion capacity. Gelation capacity and Bulk density which were in respective range of 1.68% to 2.20%. 1.06% to 2.50%, 1.99% to 6.02%, 30.11% t 0 45.92°/o, 6.01% to 0.21% and 0.06% to 0.40%. The mineral characteristics investigated were Calcium. Magnesium, Phosphorous, Iron and Zinc which were in respective range of 39.03% to 42.06%. 48.22% to 57.37%, 427.56% to 465.95%, 1.24% to 1.55% and 5.27% to 6.84%. The anti-nutrient characteristics investigated were Tannins. Oxalate, Phytate, Saponin, Alkaloid and Phenol which were in respective range of 0.31% to 0.89%, 1.02% to 1.28%, 1.01% to 3.05%. 1.10% to 2.30°/o. 1.15% to 2.38% and 0.34% to 1.75%.