EFFECTS OF INFESTATION BY BRUCHID BEETLES (CALLOSOBRUCHUS MACULATUS) ON THE NUTRITIONAL QUALITY AND SENSORY PROPERTIES OF COWPEAS (VIGNA UNGUICULATA)

The effects of insect infestation by Callosobruchus maculatus (Fabricus) on the chemical, nutritional and sensory properties of three cowpea varieties were investigated. Proximate analysis showed that infestation led to an increase in moisture content of seeds by 28.6% on the average. Decreases of 10.6%, 46.5% and 11.4% in crude protein, ash and soluble carbohydrate contents, respectively, were observed. For the three cowpea varieties, the minerals sodium, calcium and magnesium decreased by 6.7%, 10.0% and 1.3%, respectively. Indices of fat deterioration, peroxide value and free fatty acids, increased by 175% and 242%, respectively. Infestation decreased the weight gain, Protein Efficiency Ratio (PER), Feed Efficiency Ratio (FER) and blood glucose levels of experimental rats by 28.5%, 19%, 63.5% and 1.46%, respectively. Infestation also led to significant deterioration of the sensory attributes of food products developed from cowpeas. The color, aroma, taste and texture of these cowpea products were less acceptable than the sensory parameters of products made with uninfested cowpeas .