A high light pre-harvest treatment significantly extends lettuce shelf life of both intact leaves and fresh-cut

The effects of pre-harvest lighting (last days before harvest) on quality and shelf life of (fresh-cut) lettuce was investigated. Lettuce was grown in soilless culture in a vertical farm under 240 ?mol m-2 s-1 PAR from Red+White LEDs. Five days before harvest, different light intensities were applied (50, 240 and 500 ?mol m-2 s-1 PAR from Red+White LEDs) and quality at harvest and subsequent postharvest performance of intact leaves and fresh-cut product in darkness at 10?C was determined. The high light pre-harvest treatment significantly prolonged the shelf life of both the intact leaves and the fresh-cut product. This longer shelf life was related to increased levels of soluble sugars, starch and ascorbic acid at harvest. During the dark storage, levels of carbohydrates and ascorbic acid decreased over time, but at any time point, the highest levels were present in the product derived from plants that received high levels of light during cultivation. The roles of carbohydrates and ascorbic acid in postharvest tissue browning and senescence is discussed. ? Sources THE RELATION BETWEEN PRE-HARVEST LIGHT LEVELS AND POSTHARVEST PERFORMANCE OF LETTUCE Ernst J. Woltering*1, Qianxixi Min2, Celine Nicole3, Leo Marcelis2 1Wageningen UR, Food and Biobased resaerch, PO BOX 17, 6700 AA Wageningen, Netherlands 2Horticulture and Product Physiology Group, P.O. Box 630, 6700 AP , Wageningen, Netherlands 3Philips Lighting Research, High Tech Campus 7, 5656 AE Eindhoven, Netherlands *ernst.woltering@wur.nlICH2018 Istanbul, 30th International Horticultural Congress, 12-16 August 2018, Turkey Picture by Philips' City Farming: Designing The Future of Food