Optimization of the extrusion processing conditions for a banana based composite flour for weaning children 6-24 months

Abstract

The transformation of green banana flour by extrusion cooking is an alternative to add value to banana flour. This study aimed at optimizing the extrusion processing conditions for the banana composite flour for weaning children 6-24 months of age. The composite flour consisted of banana flour (B), soybean flour (S) and grain amaranth flour (A). NutriSurvey2007 software was used to optimize the ingredients in accordance with the recommended nutrient requirement for weaning children 6-24 months of age. The formulations derived were 60B:30S:10A, 60B:35S:05A, 55B:30S:15A, 55B:35S:10A, 50B:30S:20A and 50B:35S:15A. The different formulations were then analyzed for proximate composition, physical chemical properties and sensory evaluation using IBM SPSS Statistics 23; one- way analysis of variance. The formulation with the best balance of nutrients for weaning children 6-24 months of age (54.4B:35S:10.6A) was then taken for extrusion. This formulation was derived using the D-Optimal mixture design in Design expert 11 software. Design Expert 11 software was used to optimize the extrusion processing conditions of temperature (80-180oC) and moisture content (14-20%). The optimum temperature and moisture content for the extrusion of banana composite flour were 140.5oC and 20% respectively. The protein, protein digestibility and carbohydrate content were 25.052%, 75.763% and 61.593% respectively while moisture content, fiber, fat and ash were 9.1%, 1.237%, 0.923% and 3.05 respectively. The gross energy was 357.915kcal and the overall acceptability of the flour was 8.439. The protein content and gross energy which were the main elements of interest met the daily requirements of weaning children 6-24 months of age. The water absorption index and the water solubility index were 5.162% and 33.6% respectively while vitamin A content was 0.002µg/ml and vitamin C was 11.716mg/ml. The desirability of the optimum formulation was 0.707. The study findings indicated that the instant banana based weaning flour is safe for consumption within the first three months of storage.