Abstract
Total and individual carotenoid concentrations were determined in raw potato tubers of 6 varieties including Kexin No. 1, Xisen No. 6, Atlantic, Xisen No. 5, Shepody, and Favorita. The relationship between color CIE L*a*b* and total carotenoid concentration, and the effect of domestic thermal treatments on the total and individual carotenoid concentrations were also investigated. The total carotenoid content in the 6 potato varieties ranged from 96.48 to 875.08 µg/100 g FW. The main carotenoids were lutein, zeaxanthin, violaxanthin, and antheraxanthin. The specific composition depended on the variety, β-carotene was not detected in all tested six potato varieties. The color value of coordinate b* was positively and significantly correlated with total carotenoid content. Boiling had the smallest effect on the decrease of total and individual carotenoids, while microwave treatment resulted with 52.67% in the highest loss of the total carotenoid in Favorita. As for the individual carotenoids, violaxanthin followed by antheraxanthin were the most heavily affected by cooking. All four thermal treatments, baking, boiling, frying and microwave decreased the carotenoid contents, boiling is recommended as a preferred method associated the lowest loss rate of total and individual carotenoids.