Comparison of the Efficacy of Micro and Nano Emulsions of Caraway Essential Oil on Quality of Red Chili Fruits(Capsicum annuumL.) during Cold Storage

Abstract

The essential oils (EO_S) are good substitutes to antimicrobial during postharvest and can also maintain the sensory acceptability when applied to fresh fruits, the micro and nanoemulsions (ME and NE) are the most suitable and studied thanks to the ease of handling, cheap and safe.The aim of this study was to investigate the effect of ME and NE of Caraway EO on the quality parameters of red chili fruits(Capsicum annuumL.) under cold storage in 2019 and 2020 seasons. The fruits were immersed in water(control) unpackaged, polypropylene package (PP),ME at (0.05 and 0.1%) and NE at (0.05 and 0.1%) of caraway oil in PP. After immersing for 2 min in treatments, fruits were air dried for half hour at room temperature, then stored for 32 days at 7° C and 90–95% R.H. and assessed 8 days to determine the changes in fruit quality characteristics during storage. The weight loss %, decay %, fruit firmness, total soluble solids, anthocyanin content, total acidity %, and capsaicin content of red chili fruits during storage were investigated. Results showed that, all of tested ME and NE ofEO application significantly decreased weight loss, decay percentage and increased fruits storage period. Moreover, ME and NE of Caraway EO, positively, affected postharvest quality properties including fruit firmness, total soluble solids, titratable acidity, anthocyanin content and capsaicin content. It was observed that NE of EO at 0.1 and 0.05% from Caraway gave the best efficacy on weight loss, decay, firmness, total soluble solids, titratable acidity, anthocyanin content and capsaicin content than ME. Generally, NE at 0.1%PP, NE at 0.05% PP and ME at 0.1% PP treatments were the best among all treatments during the storage period.