Nanoencapsulation of Trachyspermum ammi seed essential oil in green biopolymer nanoparticles improves postharvest preservation of mushroom

Owing to the highly perishable nature of mushrooms; prolonging its postharvest attributes would be beneficial to storage industries. The objective of this study was to assess edible coatings composed of gum tragacanth (GT) nanoparticles and T. ammi (Ajwain) essential oil (AEO) and explore their potential in mushroom preservation. The AEO was accomplished by ultrasound-assisted hydrodistillation method and GC–MS analyses revealed thymol as the major constituent constituting 60.42% of AEO. The nanoencapsulation of AEO into GT was accomplished via a green route utilizing M. oleifera extract. The successful infusion of AEO was observed from FTIR study. The incorporation of AEO improved the barrier properties, thermal stability and tensile strength of the GT@AEO. The DLS studies indicated a net negative ζ-potential value for the nanoemulsions (–36.13 mV and –37.52 mV for GT@AEO 1 and GT@AEO 2 respectively). The GT@AEO 2 formulation demonstrated a shielding 99.5% for UVB and 98.7% for UVA radiations. The GT@AEO 2 displayed superior antioxidant properties in terms of DPPH and ABTS radical scavenging. Practical applications of these coatings on mushroom samples indicated lower changes in weight loss (77.41% for control and 40.86% for GT@AEO 2 -coated) and respiration rate in comparison to uncoated sample during the storage tenure of 12 days. On the 12th day of storage, the polyphenol oxidase (PPO) and peroxidase (POD) activities were inhibited by GT@AEO 2 -coating which delayed the senescence of mushrooms. Our study suggests that GT@AEO 2 has the potential to improve the quality of button mushroom and extend its shelf-life for effective preservation.