Assessment of nutritional chemicals and antioxidant activities of some food components for their potential as functional foods and prebiotics

Abstract

Functional foods are known to contain some nutritional chemicals and/or possess antioxidant properties. Therefore, this study was aimed at assessing the nutritional chemicals and antioxidant activities of date, walnut, cashew nut and bush mango seeds for their potential as functional foods. Proximate, mineral, phytochemical, anti-nutritional, antioxidant and amino acid compositions of the food samples were investigated using standard methods. The moisture content observed in the four functional foods was highest in cashew nut with a percentage value of 6.25% and lowest in walnut (4.33%). Also, cashew nut had the highest amount of protein, with a value of 28.55%. Fat ranged from 0.98 – 1.78%; There was a noticeable high amount of total carbohydrate as its value ranged from 42.45 – 56.55%. Proximate analysis also revealed low ash contents. Mineral analysis revealed the presence of magnesium, calcium, potassium, nitrogen, sodium and phosphorus. Date had the highest amount of potassium (2.67%) whereas walnut had the highest amount of phosphorus (1.22%). Energy contribution from protein ranged from 12.21 – 16.37% while that of fat ranged from 1.69 – 2.86%. Anti-nutritional analysis showed the presence of oxalate, phytic acid, tannin and cyanide. Several phytochemicals like saponin, alkaloid, flavonoid and steroid were detected in all the samples. Essential amino acids were present in the samples in varied concentrations. Concentration of glutamic acid was highest in walnut (13.02 g/100g) followed by cashew nut (12.87 g/100g). All the samples showed antioxidant activities which was significant. This study has revealed that date, walnut, cashew nut and bush mango seed possess potential as functional foods which provide a wide range of essential nutrients and antioxidant properties with many potential health benefits.