EVALUATING THE EFFECT OF POSTHARVEST UV IRRADIATION ON RED SKIN COLOR, PHENOLIC COMPOUNDS AND L. MONOCYTOGENES SURVIVAL ON HONEYCRISP APPLES

Objective 1: Determine the effect of postharvest UV irradiation treatments on enhancing red skin coloration and on fruit ripening patterns in 'Honeycrisp' apples. This first objective will function as a large screening study where we will assess the effect of single and combined postharvest UV-B or/and UV-C irradiation treatments, on enhancement of red skin coloration, chlorophyll content and fruit ripening patterns in 'Honeycrisp' apples throughout postharvest fruit conditioning (10ºC for 1 week) and a subsequent long-term cold storage (3ºC for 12 weeks + exposure to 20ºC for 1 week). Objective 2: Evaluate the effect of selected postharvest UV irradiation treatments on fruit quality, incidence of physiological disorders, accumulation of phenolic compounds and antioxidant activity in 'Honeycrisp' apples. Objective 3: Assess the impact of the selected postharvest UV irradiation treatment on Listeria monocytogenes inactivation and its survival on the skin of 'Honeycrisp' apples. Objective 4: Develop educational resources for growers and packers and extension led outreach efforts to facilitate information dissemination and implementation.