Effect of cold plasma on insect infestation and keeping quality of stored wheat flour

Abstract

Cold plasma has been applied as an alternative technology for pest control of stored commodities. Wheat flour is infested with three different insect species and subjected to plasma treatment at two power levels (40 W and 60 W) with three-time intervals. Further, the growth of larvae and pupae of insects was examined at different storage periods by sieving and visual inspection methods. There was a significant increase in the death of larvae and pupae of insects. Iodine and bromocresol green staining tests were used to detect the eggs in the flour. The parameters related to the quality of flour during the storage, like lipase enzyme activity and oxidation of fats, were analyzed. A decrease in lipase enzyme activity by 35% on the 90th days was observed in 60 W-30 min treated samples. The reduction in lipase enzyme activity resulted in a lower Thiobarbituric acid value. No significant change was observed in the color profile of wheat flour after the plasma treatment. This study shows that cold plasma can be applied as a novel technology for pest control management to enhance stored food product quality.