Effects of postharvest treatments on fruit quality of sweet pepper at low temperature.
Postharvest storage of sweet pepper fruits (Capsicum annuum L.) at low temperatures could impair their physical and chemical composition. Therefore, maintenance of essential nutrition support or altered gas exchange could preserve fruit quality, minimizing chilling injury. Thus our aim was to determine the response to postharvest application of a low concentration of nitrogen (urea) or antitranspirant (pinolene) during a period of 21 days at 5 °C. The results indicate that storage at 5 °C was effective with respect to maintaining firmness of sweet pepper fruits for 21 days, while application of antitranspirant increased firmness compared with non-sprayed fruits. Additionally, urea maintained color while increasing total phenolics and the activity of catalase and ascorbate peroxidase, lowering lipid peroxidation. Composition of free amino acids was affected to a minor extent. Maintaining quality is of paramount importance in the postharvest period. This study shows the effect of both temperature and spraying treatments with regard to maintaining fruit quality during this period, and provides new insights into the physiological role of enzymes of the antioxidant system during pepper storage at low temperature.