Nutritional qualities and aroma volatiles of harvested red pepper fruits stored at suboptimal temperatures

• Red bell pepper fruits were stored at 4 and 1.5 °C with microperforated Xtend bag – also known as quarantine treatment.
• Vitamin C, hydrophilic antioxidants and total phenols were not significantly reduced at 4 and 1.5 °C storage temperatures, compared to 7 °C.
• 2-isobutyl-3-methoxypyrazine (pepper-like volatile) remained in the fruit after 4 and 1.5 °C storage and maintained the aromatic quality.

Red pepper fruits cv. Cannon stored at suboptimal temperatures of 1.5 or 4 °C for 3 weeks followed by 3 days of shelf-life simulation were evaluated by analyzing selected quality traits and quantifying candidate aroma-related volatiles with a Gas Chromatograph-Mass Spectrometer to understand the quality associated with nutritional level and aroma. Analysis of variance showed that storage temperature and containment in microperforated Xtend® bags significantly influenced the nutritional qualities, with significant interaction between temperature and packaging material. Vitamin C, total phenolic and hydrophilic antioxidant contents were not significantly reduced (α = 0.05) at suboptimal storage temperatures of 4 or 1.5 °C in Xtend packaging, compared with those stored at the optimum storage temperature of 7 °C in Xtend® packaging. Aromatic volatiles, which create fruity, spicy, pungent, floral sweet, floral green and bell pepper-like odor notes, were observed. Most of the volatiles decreased in quantity at reduced storage temperatures when Xtend packaging was used. Particularly, 2-isobutyl-3-methoxypyrazine – the source of bell pepper-like aroma notes was found to decrease at lower storage temperatures but the fruits did not lack aroma. Thus quality and aroma of red pepper fruits can be maintained at suboptimal temperatures of 4 or 1.5 °C, which can serve as a quarantine treatment that would simultaneously eliminate Mediterranean fruit fly (Ceratitis capitata).