Development And Evaluation Of The Functional, Nutritional Quality And Consumer Perception And Acceptability Of A Sesame Seed And Peanut Based Complementary Food For Infants 6-24 Months

ABSTRACT

Malnutrition among children is still prevalent in most part of Ghana. This is very common in the rural regions of the country where cereal flour is the main source of complementary food for infants. In light of that, legumes such as cowpeas and peanuts are used to enrich the quality of complementary foods to improve child nutrition. Utilization of legumes in complementary feeding come with shortfalls such as the presence of nutritional inhibitors. In this regard, different processing techniques have been employed to ensure nutrient bioavailability and product acceptability during complementary food development. Prominent among the processing techniques are fermentation, sprouting and roasting. The goal of this work was to investigate the effects of processing methods on the functional and nutritional quality of a sesame/peanut based complementary food. A least cost formulation of complementary food with adequate nutritional profile was obtained using rice, cowpeas, and either sesame or peanuts, by the application of linear programming methodology The solution for the linear programming was to achieve a diet of minimum cost and optimum macronutrient content (protein, fat, carbohydrate and energy) in line with the WHO recommendation for complementary foods for infants between ages 6 to 24 months. Based on the solution to the linear program constraints, one formulation was obtained for products made from peanuts and that made from sesame. The design of the study after obtaining the formulations from the linear program, entailed the following factors: fermentation (fermented and non-fermented rice), sprouting (sprouted and non-sprouted cowpeas), roasting of the peanuts and sesame. The formulations were drum dried to obtain a product that could be milled into flour and easily reconstituted with water into a porridge to feed infants. Physiochemical properties, nutritional profile, in-vitro protein digestibility, mineral bioavailability and phytate levels of all the formulations and drum dried products were evaluated. Microbiological safety evaluation consisted of coliforms, yeast and moulds, E. coli and aflatoxin levels. Particle size distributions and moisture sorption behaviour of each flour were studied to assure final product texture (and consistency) as well as flour storage stability (under varying relative humidity’s). Profitability and cost analysis of the products were evaluated to satisfy the minimum cost requirements of the linear programming procedure. 

Micronutrient inhibitor (phytate) content was significantly lower in samples containing sprouted cowpeas than in samples containing non-sprouted cowpeas. Samples with sesame seeds showed higher digestibility than those with peanuts. Drum drying increased the water absorption capacity, swelling and solubility indices of the formulations. Formulations using fermented rice and sprouted cowpeas had higher L* values. The total colour difference (ΔE) of the formulations increased after drum drying due to browning. Drum drying of the formulations increased the resistant starch levels from 0.35±0.0 to 4.45±0.04. The average particle size was higher for drum dried products that incorporated fermented rice, sprouted cowpeas with either sesame or peanuts than those that had unfermented rice and non-sprouted cowpeas with either sesame or peanuts.  Formulations made using fermented rice and sprouted cowpeas with either sesame or peanuts had higher moisture sorption at room temperature (i.e. more hygroscopic) and may not keep long without good moisture barrier packaging. 

The uncooked formulations (flours) containing fermented rice flour were more acceptable to caregivers than when drum dried. Formulations with fermented rice, sprouted cowpeas and either peanuts or sesame were liked less than those with non-fermented rice, unsprouted cowpeas with either sesame or peanuts. However, drum dried formulations containing non fermented rice (and sesame or peanuts) were more acceptable to caregivers.  

All the products indicated a positive outcome in terms of cost. However, drum dried samples containing sesame showed the highest net present value of about GH₵161,202 per 10 years processing time. The results suggest that fermentation and sprouting has the potential of enhancing the nutritive value of complementary foods and acceptable alternative uses for sesame seeds and peanuts for infant nutrition