Background: The present study estimated nutrient composition of walnuts before and after cooking with respect to its potential as valuable source of nutrients for daily intake.
Method: Walnut fruits were purchased from five different markets in Ijebu-Ode local government area and its environs. The fruits samples were divided into two portions, labelled R (for raw) and C (cooked). The C samples were cooked at 100 degrees C for 1 hr and allowed to cool to room temperature. The seeds of both C and R samples were ground and analyzed for proximate, macro and micro minerals using methods of Association of Official Chemists.
Results: The results obtained showed that both raw and cooked walnuts are rich in fat, iron (Fe), manganese (Mn), and copper (Cu) in amounts that are within daily recommended intake per 100 g of walnut seeds. They also contained appreciable levels of protein, phosphorus (P), calcium (Ca), and magnesium (Mg) but with low content of moisture (MC), carbohydrate, fiber, sodium (Na) and potassium (K). Boiling significantly affected the levels of protein, carbohydrate, ash, moisture content, fat, nitrogen, calcium, sodium, copper, zinc, phosphorus, potassium, manganese and iron
Conclusion: The study reveals that walnut is nutritious due to its appreciable level of protein and presence of various essential and macro minerals. Its low content of sodium and potassium is beneficiary in hypertensive condition as snack. The study suggests future bio-fortification of walnut with zinc, which may bring about a co-increase in Ca and protein content.