Microperforated-based modified atmosphere incorporated with vapors of oregano essential oil to preserve blackberry fruits in postharvest

Abstract

Blackberry fruits have a shelf life of 3 d at ambient temperature, due to fungal development. Essential oils (Eo) can increase shelf life because of their antifungal potential. The objective was to evaluate the use of modified atmosphere packaging incorporated with vapors of an Eo to prolong shelf life of blackberry fruits. The methodology included the use of oregano Eo to inhibit fungi development. Eo was analyzed with gas chromatography-mass spectrometry. The minimum inhibitory concentration of Eo to inhibit fungi in blackberry fruits was determined in vitro and in vivo. The storage of blackberry fruits under modified atmosphere with vapors of oregano Eo was evaluated at ambient temperature. The compounds linalool, o-cymene, and thymol were identified as the main constituents of Eo. Based on fruits with fungal development, isolates were made in culture media and the presence of Aspergillus carbonarius, Alternaria alternata, and Penicillum digitatum was identified. A minimum inhibitory concentration of Eo in the head space of fruits was found with value of 0.8 μL·mL-1. The handling of blackberry fruits in modified atmosphere with micro-perforation and exposition to volatilized Eo (MAP-Eo) reduced the rate of weight loss, the loss of consistency, and that of alteration of color attributes, which allowed maintaining a better appearance during 6-7 d at 23 °C. MAP-Eo kept the content of phenolic compounds and anthocyanins, as well as the antioxidant capacity, without significant changes. In conclusion, MAP-Eo is a useful alternative to extend shelf life of blackberry fruits.