Unique tomatoes tops in disease-fighting antioxidants

Deep red tomatoes get their rich colour from lycopene, a disease-fighting antioxidant. A new study, however, suggests that a special variety of orange-coloured tomatoes provides a different form of lycopene, one that our bodies may more readily use.

Researchers found that eating spaghetti covered in sauce made from these orange tomatoes, called Tangerine tomatoes, caused a noticeable boost in this form of lycopene in participants' blood.

"While red tomatoes contain far more lycopene than orange tomatoes, most of it is in a form that the body doesn't absorb well," said Steven Schwartz, the study's lead author and a Professor of food science and technology at Ohio State University.

"The people in the study actually consumed less lycopene when they ate sauce made from the orange tomatoes, but they absorbed far more lycopene than they would have if it had come from red tomatoes. That's what is so dramatic about it."

The tomatoes used for this work were developed specifically for the study " these particular varieties aren't readily available in grocery stores.

The tomatoes were grown at an Ohio State-affiliated agricultural research station in northwestern Ohio. Following harvest, both tomato varieties were immediately processed into canned tomato juice and concentrated. Italian seasoning was added for taste.

The 12 adults participating in the study ate two spaghetti test meals " one included sauce made from tangerine tomatoes, while the other featured sauce made from the tomatoes high in beta carotene. The participants were asked to avoid tomato and beta carotene-rich foods for 13 days before eating each test meal.

Researchers drew blood right before each participant ate and again every hour or two up to 10 hours after the meal. They analysed the blood samples for lycopene and beta carotene content.

Lycopene absorption from the tangerine tomatoes was 2.5 times higher than that absorbed from the beta carotene-rich tomatoes and, Schwartz said, from typical red tomato varieties.

Cis-lycopene levels spiked around 5 hours after eating the tangerine tomato sauce, and at this point during absorption the levels were some 200 times greater than those of trans-lycopene, which were nearly non-existent. While cis-lycopene is by far the most abundant isomer in these tomatoes, they do contain trace amounts of trans-lycopene.

The participants' bodies also readily absorbed beta carotene from the beta carotene-rich tomatoes.