Effects of Fermentation Time and Blending Ratio on Functional Properties and Organoleptic Acceptability of Complementary Food

Abstract

High bulk and poor in organoleptic acceptability are a major characteristics of most complementary food used in developing countries. Fermentation and blending are afeasible approach to reduce bulkiness and organoleptic acceptability of such complementary foods. Therefore,this study aimed to develop nutritionally adequate and organoleptically acceptable complementary food from composite flour. Three fermentation times (0, 24 and 36 hr) and four blends of composite flour consisting of maize, haricot bean, and cooking banana, respectively, in the proportion of 65:20:15, 60:30:10, 50:35:15, 30:60:10 were used in the formulation with 100% maize as control. Fermentation causes significant (P ˂ 0.05) reduction in bulk density from 0.90 to 0.59g/ml, dispersibility from 63.59 to 60.72%,and swelling power from 4.55 to 4.38 g/g. On the other hand increment of water solubility index from12.45 to 14.16% and water absorption capacity from 134.38 to 158.40% were recorded as fermentation time increased. Blending ratio significantly (P ˂ 0.05) influenced some functional properties of composite flour. Bulk density ranged from 0.71 to 0.75 g/mL, water absorption capacity from 136.11 to 165.72%, dispersibility from 47.06 to71.83%, swelling power from 4.28 to 4.57g/g and water solubility index from 9.81 to 17.18%.The sensory acceptability of complementary food prepared in the form of porridge was evaluated by panelists. Among all the proportions, 60, 30 and 10% of maize ,haricot bean and cooking banana blends, respectively, fermented for24h rwas organoleptically highly preferred by panelists. Therefore, fermentation and substitution of maize with haricot bean and cooking banana could be, recommended in the production of nutritious and organoleptically acceptable complementary food for older infants and young children. Sensory acceptability of produced complementary porridge samples were carried out by a panelist consisting of 30 people selected from mothers and staff members of Melkassa Agricultural Research Center. Panelists evaluated the acceptability of sensory attributes such as color, flavor, texture, aroma, taste and overall acceptability of complementary porridge based on a seven-point hedonic scale. Those hedonic scales were 7= like extremely, 6=like moderately, 5=like slightly, 4= neither like nor dislike,3= dislike slightly, 2=dislike moderately and 1= dislike extremely. The complementary porridge was placed on a cleaned plate, served in a bright and well ventilated room. All evaluation sessions were held at Melkassa Agricultural Research Center in the food Product development room. Sensory evaluation was carried out after product cooled to room temperature. Instruction was provided to panelists on how to use sensory evaluation forms and terminologies of sensory attributes.