The effects of low-dose gamma irradiation and storage time on carotenoids, antioxidant activity, and phenolics in the potato cultivar atlantic

Abstract

Potatoes are stored to ensure a continuous supply; however, losses due to shrinkage and sprouting can be large. It is believed that low-dose ionizing irradiation will become more prominent for sprout inhibition due to the increasingly higher operating costs of low-temperature storage and the possible phase-out of chemical sprout inhibitors. The effects of storage and gamma irradiation on carotenoid content, antioxidant activity (AOA), and phenolic content were analyzed for the potato cultivar Atlantic. Tubers were subjected to 0, 75, and 200 Gy gamma irradiation doses, stored at 20 C, and analyzed after 0, 10, 20, 75, and 110 days in storage. Total carotenoid content determined via spectrophotometry decreased, while lutein content increased with storage. AOA appeared to first decrease and then increase, possibly due to dehydration, concentration, and/or induced stress. Phenolic content increased more with storage than with gamma irradiation. However, levels of some phenolic compounds, such as quercetin dehydrate, decreased with storage. Irradiation dose exerted a limited influence on AOA and phenolic and carotenoid contents. Interaction between storage time and irradiation dose was significant for AOA and phenolic content, but not for carotenoid content. Overall, storage exerted a much greater influence on carotenoid content, AOA, and phenolic content than did low-dose gamma irradiation.