Effect of Hot Water Treatment and Evaporative Cooling on Some Postharvest Characteristics of Sweet Pepper (Capsicum annuum cv. ‘Sweet Cayenne’)

Abstract

Sweet pepper is an economically important vegetable crop that is widely cultivated in many countries. However, sweet pepper incurs considerable postharvest losses due to its high perishability as manifested by shriveling and disease development. This study evaluated the effects of hot water spray treatment (55 °C) and evaporative cooling (25.6±1.31 °C, 98.87±2.07% relative humidity [RH]) as storage option on some physico-chemical attributes of ‘Sweet Cayenne’ sweet pepper. The evaporative cooler (EC) provided a microclimate with 27.96% higher RH and a temperature that was 0.41 °C lower compared to ambient storage conditions. Temperature reduction was very slight but the conditions in the EC resulted in reduced weight loss and shriveling, better visual quality, delayed color development and generally longer period of acceptable quality compared to the control fruit stored in ambient. Hot water treatment alone did not pose any significant effect in maintaining the quality of sweet pepper but tended to slightly maintain quality when combined with storage in the EC. Total soluble solids were affected only at nine days after treatment. Results showed the potential of evaporative cooling in maintaining the postharvest quality of sweet pepper and extending its shelf life by three days compared to storage in ambient conditions. The EC design may be improved to prevent surface moisture in the stored produce in order to reduce decay.