Submitted to: Journal of Food Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/22/2007
Publication Date: 10/1/2007
Citation: Ishida, B.K., Roberts, J.S., Chapman, M.H., Burri, B.J. 2007. PROCESSING TANGERINE TOMATOES: EFFECTS ON LYCOPENE-ISOMER CONCENTRATION AND PROFILE. Journal of Food Science. Vol.72, Nr.6; C307-C312, 2007.
Interpretive Summary: Tangerine tomatoes are an heirloom variety of tomato. They are similar to Beefsteak tomatoes in size and shape, but have a bright orange color. Raw Tangerine tomatoes are an excellent food source of a form of lycopene that is easily absorbed by the human body. Lycopene may help prevent prostate cancer and other degenerative diseases. We describe a method for preserving and canning Tangerine tomatoes. Unfortunately, we found that the form of lycopene found in Tangerine tomatoes is less stable than the form found in red tomatoes. Most (80%) of the absorbable lycopene was destroyed during canning. Most of the loss occurred at the first heating step of food preparation. Even so, canned Tangerine tomatoes appear to be a good source of absorbable lycopene. Therefore, further work should be done to improve food processing methods for Tangerine tomatoes.
Technical Abstract: Because lycopene is a powerful biological antioxidant, its delivery to humans is of major concern. cis-lycopene isomers are more bioavailable than the all-trans isomers and thus more efficiently absorbed. Tangerine tomatoes, whose lycopene isomeric content is almost all tetra-cis, provide a useful food source for comparing cis- and trans-isomer absorption. Tangerine tomatoes were processed into sauce in the Univ. of California, Davis Pilot Plant for subsequent use in a human feeding study described in another publication. Samples were taken at several stages during processing and carotenoids extracted and analyzed for carotenoid-isomer profiles and concentrations. Analyses showed that total lycopene concnetration decreased considerably during the 1st step of processing, which included heating and juicing operation. Processing resulted in a large decrease in tetra-cis lycopene concentration accompanied by increases in trans-and other cis-lycopene isomers.