According to new research by Wageningen UR Greenhouse Horticulture in collaboration with Philips, exposing tomatoes to extra light from LED lamps during the growing process boosts the fruit’s nutritional value by nearly doubling the amount of vitamin C.

The partnership will be continued in a joint facility for research into the application of LED lamps in horticulture (IDC LED) that will open May 16 in Bleiswijk.

Scientists at Wageningen UR studied several tomato varieties and various intensities of light. They used special LED modules that were suspended between the plants around the tomato clusters. The tomatoes normally hang in the shade as they grow beneath the leaves, a little below the top of the plant. The LEDs therefore exposed the tomatoes to a little extra “sunlight."

In the tomato variety that showed the strongest reaction, the tomatoes receiving extra light from the LEDs contained up to twice as much vitamin C as the tomatoes not exposed to the LEDs. The doubling of the vitamin C level was achieved with an extra dose of light similar to 25% of the natural light intensity on a sunny day.

Research started this year in cooperation with companies from across the horticulture chain is studying how the nutritional value and flavor of tomatoes and other vegetables and fruit can benefit from the use of LED lamps. A study into the preferences of consumers is used to determine the focus of the research.

Wageningen UR Greenhouse Horticulture performed its research within the framework of the project Gezond uit de Kas (Health from the Greenhouse), financed by the Dutch Ministry of Economic Affairs. In its research, Wageningen UR Greenhouse Horticulture collaborated with Philips, which is active in the field of LED lamp innovations in horticulture.