Original scientific paper DOI: 10.17508/CJFST.2019.11.1.03
Evaluation of nutritional composition, functional and pasting properties of wheat flour-coconut flour blends
Bowen University, Faculty of Agriculture, Department of Food Science and Technology, Iwo, Osun State, Nigeria
Received: February 19, 2018
Accepted: January 18, 2019
The feasibility of partially replacing wheat flour with coconut flour in baked products was investigated. Matured coconut (Cocos nucifera) endocarp was grated for extraction of milk, dried, milled and pulverized. Five blends of composite flour were prepared by combining wheat flour with 10% to 50% partially defatted coconut flour respectively. The 100% wheat flour served as control. The samples were analyzed for proximate, mineral, functional and pasting properties using standard procedures. Proximate analysis indicated 5.52 % moisture, 23.6% protein, 11.14% fiber, 5.4% fat, 5.21% ash and 49.1% carbohydrate for coconut flour. The ranges of proximate composition of flour blends were moisture (4.79-5.55%), protein (14.9 -19.1%), fiber (0.44 -5.12%), fat (2.9 -5.3%), ash (0.68-2.13%), carbohydrate (62.7-76.2%) and energy (315.26-335.28 kCal). The values for moisture, protein, fat, fibre and ash increased with increasing levels of coconut substitution except for carbohydrate and energy contents. There were significant differences (p≤0.05) in calcium, magnesium, potassium, phosphorus, iron and zinc concentrations of the samples. Values obtained for these parameters ranged from 1.32-2.59 mg/kg, 2.60-3.83 mg/kg, 12.10-16.89 mg/kg, 12.40-18.50 mg/kg, 0.50-1.22 mg/kg and 0.30-1.23 mg/kg, respectively. The ranges of functional properties were loosed bulk density (0.28-0.49 g/mL) packed bulk density (0.44-0.75 g/mL), pH (5.77-6.57), swelling capacity (3.89-6.56%), water absorption capacity (0.89-3.97 ml/g),oil absorption capacity (1.26-3.20 ml/g) and gelation (12.0-18.0%). Pasting characteristics showed significant differences between 100% wheat flour and coconut substituted samples. The results revealed modifications in nutritional, functional and pasting properties in blends containing fractions of partially defatted coconut flour which suggest their application in diverse food products.