Physical, chemical and sensory properties of cookies produced from sweet potato and mango mesocarp flours

Abstract

This study was a result of the need for utilization of local raw materials for food production and diversification as well as an attempt to reduce the rising cost of wheat imports. The objective of this study was to investigate the physical, chemical and sensory properties of cookies produced from sweet potato and mango mesocarp composite flours. Sweet potato tubers and partially ripe mango fruits were processed into flours. Cookies were prepared from blends of 90:10, 80:20, 70:30 and 60:40 sweet potato flour (SPF) to mango mesocarp flour (MMF), with cookies prepared from 100% sweet potato flour (SPF) and 100% wheat flour (WF) serving as control and standard respectively. Thereafter, all the cookie samples were subjected to chemical, physical and sensory analyses using standard methods. The moisture, fat, fibre, ash, energy values as well as beta carotene contents increased significantly (p < 0.05) as the level of substitution increased. The standard recorded the highest protein value with the control having the least value. However, the control had highest value in terms of carbohydrate. The crude protein increased significantly (p < 0.05) between the blends with increasing levels of mango mesocarp flour. Conversely, the carbohydrates content decreased as substitution levels increased. The diameter and spread ratio of the cookies decreased with increased substitution levels while the thickness increased. Cookies prepared from whole sweet potato flour were rated higher in terms of colour (8.1), crispiness (8.8), flavour (7.9), texture (7.2), taste (7.1) and overall acceptability (8.5) followed by cookies from whole wheat flour. Preference for the cookies decreased significantly (p<0.05) as the percentage of mango mesocarp flour (MMF) increased. Cookies from 60% SPF: 40% MMF had the least acceptability, though they had the highest β – carotene content. Generally, cookies produced from 100% SPF and the blends had good nutritional value except for protein which decreased with increasing levels of substitution with MMF.

Keywords: Cookies, sweet potato, mango mesocarp, physical, Chemical, Sensory, Beta carotene