Intermittent warming improves postharvest quality of bell peppers and reduces chilling injury

•Intermittent warming reduces chilling injury to peppers and extends storage life.•Two intermittent warming cycles at 6 and 13 days after harvest were optimal.•Cell microstructure and volatile flavor changes confirmed this result.•Storage life was extended by 6–11 days and delayed chilling injury onset.•Suitable timing and intermittent warming intervals are required for optimal storage.

The long-term low temperature storage of pepper fruit is currently risky because of the likelihood of chilling injury (CI), which reduces shelf-life. Intermittent warming (IW) has been proposed as a potential solution to enhance successful long-term pepper fruit storage. To understand the influence of IW in alleviating CI in peppers, the effects of 3 IW cycles were tested on the organic acid content, firmness, and relative enzyme content of pepper fruit (namely, 1–3 IW cycles to 20 °C for 24 h every 7 days for fruit stored at 4 °C for 27 days). Subsequently, the effects of 2 IW cycles were tested on the organizational structure of pepper fruit cells and potential odor changes. The results showed that IW effectively reduces the CI index and maintains pepper firmness. Following 2 IW cycles after 6 and 13 days storage, pepper integrity was retained, with no shrinkage or decay. Furthermore, partial least squares analysis of odor changes showed that both 1 IW cycle after 20 days storage and 2 IW cycles after 6 and 13 days storage extended storage time to over 10 days. The appropriate IW cycles effectively delay the decline in unsaturated fatty acid content and maintain a higher index of unsaturated fatty acids (IUFA), which helps retain the integrity of the pepper cell membranes.