| Abstract
| - Consumption of tomato products has been associated with decreased risk of some cancer types, andthe tomato antioxidant, lycopene, is thought to play an important role in the observed health effects.In this study, four carotenoids, trans-lycopene, phytofluene, phytoene, and ζ-carotene, were quantifiedin tomato products. Samples of raw tomatoes, tomato juice after hot break scalder, and final pastewere obtained from two different processing plants over two years. Comparison of carotenoid levelsthroughout processing indicated that lycopene losses during processing of tomatoes into final paste(25−30 °Brix) ranged from 9 to 28%. The initial Brix level of the raw tomatoes appeared to influencethe amount of lycopene loss that occurred, possibly due to the differences in processing time requiredto achieve the final desired Brix level of the paste. In general, no consistent changes in the othercarotenoids were observed as a function of processing. The antioxidant activity of fresh tomatoes,tomato paste, and three fractions obtained from these products (i.e., aqueous, methanol, and hexanefractions) was also determined. In both a free radical quenching assay and a singlet oxygen quenchingassay, significant antioxidant activity was found in both the hexane fraction (containing lycopene)and the methanol fraction, which contained the phenolic antioxidants caffeic and chlorogenic acid.The results suggest that in addition to lycopene, polyphenols in tomatoes may also be important inconferring protective antioxidative effects. Keywords: Carotenoids; phytofluene; phytoene; ζ-carotene; tomato paste
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