Warm Watermelon More Nutritious

July 28, 2006 -- A new study shows storing watermelon in the fridge can have a chilling effect on its nutritional value.

U.S. Department of Agriculture researchers found watermelons stored at room temperature have significantly more antioxidants and other nutrients than watermelons kept in the refrigerator.

Watermelon is a rich source of carotenoid compounds, such as lycopene and beta carotene, which are natural antioxidants linked to a number of health benefits, from fighting cancercancer to preventing sun-related skin damage.

The summertime staple contains higher levels of lycopene than any other fresh fruit or vegetable. Its red pigment is found only in a few foods, including tomatoes.

Keep Watermelons out of the Fridge

In the study, researchers analyzed the carotenoid content in several varieties of red-fleshed watermelon stored 14 days at three different temperatures: 70 degrees (room temperature in an air-conditioned home), 55 degrees, and 41 degrees (similar to a refrigerator).

Compared with freshly picked fruit, the results showed lycopene levels increased up to 40% and beta carotene levels jumped up to 139% in watermelon stored at room temperature.

In contrast, levels of these nutrients remained about the same in watermelons stored at lower temperatures.

Researchers say the average shelf life of watermelons after harvest is 14-21 days if stored at 55 degrees. But decay occurs after as little as a week when stored at refrigerator temperatures of around 41 degrees.

The study appears in the Journal of Agricultural and Food Chemistry.