Postharvest Performance of Purple and Green Near-Isogenic Peppers (Capsicum annuum) During Storage

Anthocyanin accumulation has been associated with extended shelf life and improved postharvest quality of tomato; however, whether similar effects occur in pepper remains unclear. Therefore, this study investigated purple and green near-isogenic Capsicum annuum lines at economical and biological ripeness during six weeks of storage at 10 and 25 °C. Physical quality traits, antioxidant-related parameters, individual phenolic compounds, and fruit decay were all evaluated via spectrophotometry and HPLC. Storage temperature and time strongly affected fruit quality, with higher temperature accelerating weight loss and softening. At 25 °C, purple fruits showed greater weight loss than green fruits, whereas firmness declined more strongly in green fruits, although differences between the green and purple fruits’ firmness were not significant. In contrast, the purple phenotype showed a distinct phytochemical profile, with higher total phenolic and flavonoid contents, anthocyanin accumulation, and antioxidant capacity. HPLC analyses showed fruit colour, storage time, and temperature-dependent changes in individual phenolic compounds. Spontaneous rot occurred at 25 °C, but no overall fruit colour effect on decay was detected. These results indicate that, unlike in purple tomato, anthocyanin accumulation in pepper does not necessarily confer a consistent shelf-life advantage but is associated more with possibly more advantageous phytochemical and antioxidant characteristics.