Effects of ethephon on ethephon residue and quality properties of chili pepper during pre-harvest ripening

The application of ethephon was investigated to examine its effects on both ethephon residue and quality properties of chili peppers during pre-harvest ripening with the goal of facilitating maximum commercial harvest along with improving color and flavor. A single ethephon treatment significantly increased L* and a* values and capsanthin concentration, while decreased total chlorophyll contents. Moreover, ethephon treatment induced significant promotion of capsaicin synthesis and reduction of soluble sugar content. While repeated treatments did not increase the total capsaicin content, and the consumption of soluble sugar was accelerated. Additionally, the maximum ethephon residue in chili pepper after ethephon treatment was 21.18 mg kg−1, which is lower than the permissible residue level of 50 mg kg−1 for chili peppers. The ethephon residual decreased with prolonging harvest time of chili peppers. The effects of ethephon treatment on different types of chili peppers were variable. The results of this study indicated that ethephon could hasten the ripening process and increase the quality of chili peppers.