Carotenoid profile and retention in yellow-, purple- and red-fleshed potatoes after thermal processing

Abstract

This research aimed to investigate the effect of thermal processing on carotenoid profile, quantity and stability in 22 colour-fleshed potato cultivars grown in the Czech Republic. The total of nine carotenoids was analysed by HPLC using a C30 column and PDA detection. The total carotenoid content for all cultivars ranged from 1.44 to 40.13 μg/g DM. Yellow cultivars showed a much higher average total carotenoid content (26.22 μg/g DM) when compared to red/purple-fleshed potatoes (5.69 μg/g DM). Yellow cultivars were dominated by antheraxanthin, whereas neoxanthin was the main carotenoid in red/purple cultivars. Thermal processing significantly impacted all potato cultivars. Boiling decreased the total carotenoids by 92% compared to baking (88%). Lutein was the most stable carotenoid against thermal processing (decreased by 24-43%) followed by β-carotene (decreased by 78-83%); other carotenoids were degraded nearly completely. Increased formation of (Z)-isomers by thermal processing has not been confirmed.

Keywords: Antheraxanthin (PubChem CID: 5281223); Baking; Boiling; Carotenoids; Lutein (PubChem CID: 5281243); Neoxanthin (PubChem CID: 5281247); Potato cultivars; Stability; Thermal processing; Violaxanthin (PubChem CID: 448438); Zeaxanthin (PubChem CID: 5280899); β-Carotene (PubChem CID: 5280489); β-Cryptoxanthin (PubChem CID: 5281235).