Proximate Composition of Stored Dates (Phoenix dactylifera L.) Infested with Oryzaephilus surinamensis (L.) (Coleoptera: Silvanidae)

Three date cultivars Jigawa, Deglet Noor and Mali were sourced from the open market in Gombe and infested with a pair of 2-3 days old O. surinamensis L. for 14 weeks to evaluate the effect of infestation on their nutrient composition. Nutritional status of fresh un-infested dates were also analysed before the onset of the experiment to determine their initial nutritional contents. The result shows significant increase in carbohydrates in dates after 14-weeks of storage but a decrease in in content with infestation. Findings of the research further show significant difference in nutritional composition of un-infested and infested dates after 14 weeks. Carbohydrate ranged from 74.20.2 to 66.70.6 and moisture from 12.40.4 to 16.20.1 in un-infested and infested dates respectively. In addition, percentage stored date ash content, fat, crude protein and crude fibre all decreased after infestation. Degree of post infestation carbohydrate status of the three date cultivars was in the descending order Infested Mali cultivar less than infested Deglet Noor cultivar less than infested Jigawa cultivar. On the overall, carbohydrate content of infested dates, which constitutes about 70 % of dates reduced significantly by O. surinamensis infestation, as well as the other parameters considered except moisture.