Nutritional, Functional, Microbiological and Organoleptic Properties of Breakfast Cereals Formulated from Maize, Soybean and Carrot Flour Blends

Abstract

This study was carried out to evaluate the nutrient composition, functional, microbiological and sensory properties of breakfast cereals formulated from flour blends of maize, soybean and carrot. Each sample of the flours was used at varying replacement levels (5-25%) to complement the malted maize flour in the production of breakfast cereals with breakfast cereal produced from 100% malted maize flour as control. The nutrient composition, functional, microbial and sensory properties of the breakfast cereals were determined using standard methods. The proximate composition of the samples showed that the moisture, crude protein, fat, ash and crude fibre contents of the breakfast cereals increased significantly (p<0.05) with increased substitution of soybean and carrot flours. The mineral composition of the samples showed that the calcium, magnesium, phosphorus, potassium, iron and zinc contents of the samples also increased with increase in addition of soybean and carrot flours. The vitamin composition showed that the ascorbic acid, niacin, thiamine, riboflavin, vitamin A and folic acid contents of the samples ranged from 22.19-71.61mg/100g, 62.73-120.32mg/100g, 4.36-5.57mg/100g, 5.37-6.51mg/100g, 18.62-78.75mg/100g and 3.02-3.81mg/ 100g, respectively. Result showed that the vitamin contents of the samples increased with increased substitution of soybean and carrot flours. The microbial counts of the breakfast cereal products showed that the total viable count of the samples ranged from 0.42 × 104-1.14 × 104 cfu/g, while the coliform and fungal counts were nil. The functional properties (bulk density, water absorption capacity, solubility index, gelation capacity, swelling capacity and oil absorption capacity) of the samples increased significantly (p<0.05) with increased substitution of soybean and carrot flours from 1.24-1.37 g/cm3, 35.14-93.34 ml/g, 48.76-91.67 %, 42.42-71.15 g/g, 4.77-9.15 g/g and 1.41-5.81 g/g, respectively. The sensory properties of the samples showed that the porridge prepared from the breakfast cereal made with 100% malted maize flour was the most acceptable by the judges and also differed significantly (p<0.05) in colour, texture, taste and aroma from composite flour breakfast cereals. Although the porridge made from the control sample was organoleptically most acceptable, the porridges prepared from the formulated breakfast cereal samples were also rated high in all the sensory attributes evaluated by the judges. The study, however, showed that the nutrient contents and functional properties of maize-based breakfast cereals could be improved by substituting the maize flour with soybean and carrot flours at varied proportions in the preparation of the breakfast cereal products.