High-Relative-Humidity Storage Reduces the Chilling Injury Symptoms of Red Sweet Peppers in the Breaker Stage

Abstract

Water loss, interwoven with other factors, is identified as the cause of chilling injury to sweet peppers. The breaker stage is the most vulnerable of all maturity stages. The purpose of this study was to see if increasing the storage relative humidity (RH) reduces the chilling injury and to compare its effect on breaker-stage fruits to red-ripe fruits at a normal RH. The fruits were stored at 5 °C with a RH of 98 ± 2% and 70 ± 6% for high and low RH, respectively. After 15 days of cold storage, the fruits were moved to ambient conditions for 3–5 days for chilling injury symptoms to appear. The results showed that high RH storage reduced fruit water loss by 4–4.5% compared to low RH storage, resulting in fewer chilling injury symptoms regardless of fruit maturity stage. Due to the increased RH, cell membrane damage indicators such as electrolyte leakage, MDA, respiration, and ethylene production rates were shown to be reduced, while brix and color were well maintained, indicating reduced or stopped senescence. Furthermore, DPPH antioxidant activity and vitamin C were retained and optimized. The microbiological analyses also showed that a high RH may not promote the growth of microorganisms as quickly as may have been thought. Finally, the findings of this study indicate that breaker-stage peppers stored at a high RH may be less susceptible to chilling injury than red-ripe peppers stored at a low RH.

Keywords

• breaker stage
• cold storage
• high RH
• low RH
• red-ripe