Combined effect of UV-C, ozone and electrolyzed water for keeping overall quality of date palm

The work presented here aims to contribute with a sustainable alternative to chemicals for avoiding deterioration of harvested date palm fruits by evaluating the single or combined use of UV-C radiation and ozonated or electrolyzed water (EW). In this way, the effects of UV-C light (0; 2.37; 6.22; 8.29 and 12.14 kJ m(-2)) alone, and the combined effect of 6.22 kJ m(-2) UV-C with neutral EW (NEW, pH 6.99, 870 mV ORP, 100 mg L-1 free chlorine), alkaline EW (AEW, pH 11.28, -880 mV ORP, 1.83 mg L-1 free chlorine) and ozonated (O-3, 0.55 mg/L ozone) water on overall quality of Deglet Nour dates stored for 30 days at 20 degrees C were studied. Microbial growth, weight loss, firmness, pH, titratable acidity, moisture, water activity, sugars and phenolics content, antioxidant activity color and sensory quality were monitored. UV-C light, mainly at 6.22 kJ m(-2), alone or combined with NEW, AEW and O-3, kept the overall quality of dates during storage, Moreover, those treatments reduced the most mesophilic, coliforms, yeasts and molds counts. In summary, these combined emergent sanitizers could be useful for disinfection of fresh dates while keeping quality and prolonging shelf-life. (C) 2014 Elsevier Ltd. All rights reserved.