Location: Sugarcane ResearchTitle: The use of low-dose electron-beam irradiation and storage conditions for sprout control and their effects on xanthophyllis, antioxidant capacity, and phenolics in the potato cultivar Atlantic
|BLESSINGTON, TYANN - Texas A&M University|
|SCHEURING, DOUGLAS - Texas A&M University|
|NZARAMBA, M - Texas A&M University|
|REDDIVARI, LAVANYA - Texas A&M University|
|VESTAL, TOM - Texas A&M University|
|MAXIM, JOSEPH - Texas A&M University|
|MILLER, JR., J - Texas A&M University|
Submitted to: American Journal of Potato Research
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/19/2015
Publication Date: 9/25/2015
Citation: Blessington, T., Scheuring, D., Nzaramba, M.N., Hale, A.L., Reddivari, L., Vestal, T.A., Maxim, J., Miller, Jr., J.C. 2015. The use of low-dose electron-beam irradiation and storage conditions for sprout control and their effects on xanthophyllis, antioxidant capacity, and phenolics in the potato cultivar Atlantic. American Journal of Potato Research. 92(5):609-618.
Interpretive Summary: To ensure a year-round supply of potatoes, much of the crop is stored for extended periods of time. During storage, potatoes have a tendency to sprout, rendering them unsuitable for processing. Low-temperature storage along with chemical sprout inhibitors are used to prevent sprouting in stored potatoes. An alternative to chemical treatment is the use of ionizing or e-beam radiation to prevent sprouting. E-beam irradiation does not raise the same disposal and storage concerns as ionizing radiation, and is being explored as another possible alternative for sprout inhibition. While e-beam irradiation has been shown to inhibit sprouting in potato, little is known about the effects of low-dose e-beam irradiation on the level of health-promoting antioxidants in potato. In this study, the effects of storage and low-dose e-beam irradiation on health promoting compounds were evaluated in the potato variety ‘Atlantic’. Potatoes were exposed to radiation at room temperature and low temperatures and were stored for varying amounts of time. The levels of the following three different types of antioxidants were measured in response to storage and irradiation: total antioxidants, total xanthophylls and total phenolics. Specific compounds within these classes were also measured. Potatoes exposed to irradiation did not sprout, while those that were not exposed did. Potatoes that were not stored under cold temperatures were dehydrated. Exterior layers of the potato (those exposed to irradiation) had a higher level of all three types of antioxidants than those that were not exposed. Following irradiation, levels of antioxidants increased during the first 10 days of storage, but little or no difference was observed between irradiated and non-irradiated tubers at the end of the storage period. E-beam irradiation did not significantly affect health-promoting compounds in potato following long-term (110 day) storage.
Technical Abstract: The effects of storage and low-dose electron-beam (e-beam) irradiation on health-promoting compounds were evaluated in the potato cultivar Atlantic. Tubers were either not exposed or subjected to 200 Gy and were either sampled immediately or stored at either 4 degrees C or ambient temperature for 10, 20, 75, and 110 days before evaluation. Xanthophyll content (Xan), antioxidant capacity (AOC), and phenolic content (PC) were quantified by spectrophotometric absorbance; xanthophyll and phenolic compounds were quantified with HPLC analysis. Tubers held at ambient conditions during storage lost weight and were visibly dehydrated. Tubers exposed to irradiation did not sprout; non-irradiated tubers sprouted, regardless of storage temperature. E-beam irradiation is largely a surface treatment, and in a separate analysis the exterior and interior surfaces of tubers were evaluated. The exterior layer of tubers had greater total Xan, AOC, and PC than the interior layer, regardless of treatment. In an analysis of variance, storage time was the only parameter that significantly influenced Xan, AOC, and PC content of whole, exterior and interior surfaces of tubers. Irradiation and storage caused only minimal changes in Xan. AOC, PC, and chlorogenic acid content increased within the first 10 days of storage and then declined with extended storage. Initially, the AOC and PC increased in irradiated tubers when compared to non-irradiated samples; however, little to no differences were observed once tubers were held in storage. Some exterior layer samples experienced an increase in Xan and PC during the later stages of storage and was believed to be associated with a concentration effect due to dehydration. E-beam irradiation inhibited sprouting during extended storage, and prominent potato health promoting compounds were retained.