Takeoka G R, Dao L, Flessa S, Gillespie D M, Jewell W T, Huebner B, Bertow D, Ebeler S E
Western Regional Research Center, Agricultural Research Service, U.S. Department of Agriculture, Albany, California, USA.
J Agric Food Chem. 2001 Aug;49(8):3713-7. doi: 10.1021/jf0102721.
Consumption of tomato products has been associated with decreased risk of some cancer types, and the 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 zeta-carotene, were quantified in tomato products. Samples of raw tomatoes, tomato juice after hot break scalder, and final paste were obtained from two different processing plants over two years. Comparison of carotenoid levels throughout processing indicated that lycopene losses during processing of tomatoes into final paste (25-30 degrees Brix) ranged from 9 to 28%. The initial Brix level of the raw tomatoes appeared to influence the amount of lycopene loss that occurred, possibly due to the differences in processing time required to achieve the final desired Brix level of the paste. In general, no consistent changes in the other carotenoids 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 hexane fractions) was also determined. In both a free radical quenching assay and a singlet oxygen quenching assay, 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 in conferring protective antioxidative effects.
食用番茄制品与某些癌症类型的风险降低有关，番茄抗氧化剂番茄红素被认为在观察到的健康影响中起重要作用。在本研究中，对番茄制品中的四种类胡萝卜素，即反式番茄红素、八氢番茄红素、六氢番茄红素和ζ-胡萝卜素进行了定量分析。在两年时间里，从两家不同的加工厂获取了生番茄、热破碎杀菌后的番茄汁以及最终番茄酱的样本。对整个加工过程中类胡萝卜素水平的比较表明，番茄加工成最终番茄酱（25 - 30波美度）时番茄红素的损失率在9%至28%之间。生番茄的初始波美度似乎会影响番茄红素的损失量，这可能是由于达到最终所需番茄酱波美度水平所需的加工时间不同所致。一般来说，未观察到其他类胡萝卜素随加工过程有一致的变化。还测定了新鲜番茄、番茄酱以及从这些产品中获得的三个组分（即水相、甲醇相和己烷相）的抗氧化活性。在自由基淬灭试验和单线态氧淬灭试验中，在己烷相（含番茄红素）和甲醇相中均发现了显著的抗氧化活性，甲醇相中含有酚类抗氧化剂咖啡酸和绿原酸。结果表明，除了番茄红素外，番茄中的多酚类物质在赋予保护性抗氧化作用方面可能也很重要。
