Nutritional and Sensory Quality of Extruded Oat, Soybean and Linseed Complementary Instant Food.

Abstract

In Ethiopia child malnutrition is enormous challenge. Besides preparation and processing method, one of the major problems associated with macro and micronutrient deficiency in traditional complementary food is that, it is only from cereal source. Using blends of cereal, pulse and oilseed extruded composite flour(ECF) can solve these problems by improving nutritional quality; reducing macro and micro-nutrient deficiencies and producing safe and instant complementary food that needs minimum cooking time to reduce loss of heat liable nutrients. The blend of oat, soybean, linseed flour and premix (sugar, salt, moringa & fenugreek) composite flour was developed. Thirteen formulations of the composite flour were generated using D-optimal constrained mixture design with a range of oat 55-65%, soybean 11-23%, linseed 6-11% and 15%. A premix was added in equal proportion to all treatments to improve taste, flavor, mineral and vitamin. The blend was extrusion cooked at 130ºC barrel temperature( BT), 150 rpm screw speed, (with the feeder delivering a feed rate of 5.1g/min; feed moisture content in the extruder barrel was 17% (170 g/kg). Nutritional and sensory qualities of the ECF were investigated using standard methods. The major responses of nutritional composition (protein, fat, carbohydrate, energy, β-carotene, iron, zinc and calcium, anti-nutritional factors (phytate and tannin), functional proprieties (bulk density, water absorption capacity) and sensory quality were analyzed. The results showed a significant (P < 0.05) difference in fat, protein, carbohydrate, ash, fiber, calcium, phytate, tannin, water absorption capacity (WAC) and bulk density of the ECF. The protein, fat, energy, tannin, phytate and mineral contents of the ECF increased with increasing ratio of soybean and linseed. However sensory acceptability and β- carotene content was decreased with increasing proportion of soybean in the blend. There was significant (P < 0.05) difference for aroma, taste, and consistency and over all acceptability of the gruel but appearance and mouth feel showed no difference for gruels. The blend ratios at 58.4%, 18.4% and 8.2% oat, soybean and linseed respectively were selected as overall optimum blend ratio with desirable nutritional composition which varied between 19.0-20.64%protein, 8-9.9% fat, carbohydrate 60.92- 63.7, 394.98-408.2kcal energy, 110- 124.4 mg/100 g calcium, 7-7.8 mg/100 g iron, 2.96-3.0 mg/100 g zinc, 1600- 1900.3 µg/100 g, β- carotene and sensory attributes 3.75-4 overall acceptability (5 point hedonic scale).Extrusion cooked oat, soybean linseed blend enriched with premix showed significant improvement in the nutritional quality and sensory attributes. The result revealed that, the blend had good potential of improving protein, fat, energy, zinc, iron, & β-carotene of complementary food. Hence, using this optimum amount of formulation can enrich the nutritional value of CF.