Effect of feed and process variables on nutritional quality of maize-millet based soy fortified extruded product using response surface methodology.

Composite flour comprising of maize, finger millet, defatted soy and elephant foot yam in the ratio of 40:30:20:10 was utilized for the development of an extruded product. The experiment was conducted to study the effects of process variables, namely barrel temperature: 100-150°C, screw speed: 110-350 rpm and feed moisture: 12-20% (wb) on the nutritional quality of product by using Response Surface Methodology (RSM). The nutritional qualities like moisture content, carbohydrate content and protein content were affected significantly by barrel temperature, screw speed and feed moisture content, but fat and crude fiber content did not indicate any appreciable variation with process variables. The nutritional values of extruded products were found to be vary from 6.14 to 9.78% product moisture, 13.96-16.81% protein, 0.49-1.07% fat, 64.99-72.98% carbohydrate, and 2.48-3.36% fiber content. All rights reserved, Elsevier.