Quality Attributes of Weevils (Callosobruchus Maculatus) Infested Cowpea (Vigna Unguiculata) Products
No Thumbnail Available
Date
2013
Journal Title
Journal ISSN
Volume Title
Publisher
Nigerian Journal of Agriculture Food and Environment, Published by Faculty of Agriculture, University of Uyo, Uyo, Nigeria
Abstract
Cowpea is an important food legumes widely consumed in almost every part of the world including Nigeria. The cowpea seeds are often rendered worthless by the cowpea weevils (Callosobruchus Maculatus).This infestation usually originate in the field and continue progressively in stored seeds. This study therefore evaluated the growth rate of weevils, weight loss of the stored cowpea seeds, and the effect of weevils on the proximate, functional and sensory properties of cowpea products (cowpea flour and akara). Akara is a deep-fat fried ball prepared from whipped cowpea paste, flavoured with pepper, onion and salt. Twenty five (25) matured weevils were inoculated into 6.4kg of fresh uninfested cowpea seeds and stored at room temperature (25 ± 5°C) for 4 weeks duration of the study. The number of live weevils was counted and the weight of cowpea seeds was measured weekly and Samples were taken weekly from the stored weevil infested cowpea seeds, milled into flour and evaluated for proximate composition and functional properties. The flours were subsequently used in the production of akara and subjected to sensory evaluation. Data obtained were subjected to analysis of variance test and means separated at 5% probability level. Proximate composition of the flours varied significantly with moisture (10.51-11.51%), ash (3.01-3.20%), protein (16.4619.61%) and fat contents (1.12-1.40%) decreasing with increase in the duration of storage period while carbohydrate (63.2467.86%) and crude fibre (0.91-1.01%) increased. All the functional properties including loose bulk density (0.56-0.66g mL-1), packed bulk density (0.75-0.86g mL-1), water absorption capacity (1.00-1.25 g water g-1 flour) and oil absorption capacity (0.8-1.10 g water g-1 flour) decreased significantly as duration of storage increased. A similar trend observed for the flours was obtained for the proximate composition of the akara samples with moisture (10.52-11.63%), ash (3.59-3.82%), protein (16.60-19.97%) and fat contents (2.06-2.30%) decreasing with increase in duration of storage, while carbohydrate (61.4166.21%) and crude firbre (0.88-0.97%) increased. Sensory attributes of akara produced from uninfested cowpea flour was the most acceptable, flour from one week infested cowpea was comparable with the uninfested cowpea flour in aroma, taste, texture and acceptability. Generally, panelist described the texture of akara made from these flours as dry with a tough outer surface and a beany flavor
Description
Keywords
Quality attributes, Cow pea storage, Weevil infestation, Akara production, Cowpea flour
Citation
Oyeyinka et al., (2013)