Changes in Contents of Carotenoids and Vitamin E during Tomato Processing

The aim of this study was to investigate the effect of different types of tomato processing on contents of lycopene, β-carotene, and α-tocopherol. Samples of tomato sauce, tomato soup, baked tomato slices, and tomato juice were taken at different times of heating, respectively, after each step of production. HPLC was used to analyze contents of carotenoids and vitamin E. Due to the loss of water during thermal processing, contents of lycopene, β-carotene, and α-tocopherol on a wet weight basis increased. On a dry weight basis, contents of lycopene increased or decreased depending on the origin of the tomatoes used, whereas the β-carotene contents decreased or were quite stable. In contrast to lycopene, β-carotene isomerized due to thermal processing. The α-tocopherol contents significantly rose during short-term heating. The increase was not caused by release of α-tocopherol from the seeds containing predominantly γ-tocopherol and accounting for 2% of total α-tocopherol content only. Keywords: Carotenoids; vitamin E; tocopherols; tomato