Rocket salad grows with more vitamin C under LED lights
The vitamin C-rich arugula produced at Philips Lighting’s GrowWise Research Center were tested to have seven times higher vitamin C content than the published USDA (United States Department of Agriculture) value of 15 mg/100 gr. The vitamin C-rich arugula was grown in a trial in collaboration with the Dutch Wageningen University and Research, and Maastricht University, using a new growth recipe under Philips LED lighting in a vertical farming environment with no daylight.
The results of this trial show that functional ingredients can be added to fresh food like arugula by simply growing it differently. Retailers and growers can apply specific Philips light recipes using LED technologies to meet the growing demand for functional foods from health-conscious consumers. Since vitamin C is one of the markers of shelf life, the higher vitamin C levels in the arugula at harvest may also help retailers extend the popular green’s shelf life, notes Philips Lighting. In addition to vitamin C, other healthy compounds are shown to be influenced by the growth recipe.
“A Philips growth recipe provides parameters for growing a crop that include the light level, spectrum, intensity, required uniformity, position and time, as well as climate conditions like temperature, humidity, CO2 levels and nutrition” explains Udo van Slooten, Managing Director for Philips Lighting Horticulture LED Solutions. “This achievement confirms the tangible benefits that our research at Philips GrowWise Center is delivering for growers and retailers as they look to meet specific consumer needs like optimized smell, taste and flavor to differentiate themselves in their markets.”
Light influences nitrate level
The arugula grown under the LED lighting with the new Philips growth recipe showed a very low nitrate level while having a high yield. Lower nitrate levels also have higher sugar levels and a milder taste. The leaves grown under the LED lighting scored between five and eight on the Brix index, which correlates with a higher perception of sweetness in sensory tastes. The low nitrate levels achieved in this trial are considerably lower than those set by the European Union, which range from 7000 mg/kg to 6000 mg/kg). This low-nitrate arugula would help retailers in Poland, Russia and Finland to meet the growing demand for low-nitrate foods from consumers in these countries. By using another growth recipe, it is also possible to grow a high vitamin C arugula with a high nitrate content for consumers willing to use high rich nitrate content as a health benefit without affecting the production of other nutritious compounds.
The arugula crop was tested in four different lighting situations with three different LED lighting combinations and one artificial light source that mimicked the sun and/or HPS lighting. The effects of high blue and high far red wavelengths were also studied to determine their impact on shelf life and nutrient content of the harvested greens.
Philips Lighting – www.philips.com/horti