Long-acting sustained release microcapsules of oregano essential oil-loaded gelatin/carrageenan for food preservation against Botrytis cinerea

As a food-derived natural component, oregano essential oil (OEO) exhibits excellent activity against Botrytis cinerea (B. cinerea). However, its poor water solubility and chemical instability limit its application in preservation. In this study, we determined the composition of OEO and encapsulated it in microcapsules using gelatin/carrageenan (GE/CRG) as the capsule wall, achieving a particle size of 336.10 nm and an encapsulation efficiency of 87.79 %. The microcapsules realize the slow-release duration of OEO to over 80 h. More importantly, due to the slow-release effect of OEO, OEO-GE/CRG microcapsules demonstrated excellent inhibitory activity against B. cinerea with an EC50 value of 0.18 mg/mL. The microcapsule treatment significantly prolonged the preservation period of cherry tomatoes in infection models with B. cinerea. These results indicate that OEO-GE/CRG microcapsules could serve as a potential fungal inhibitor and agent for fruit storage and preservation. •The OEO-GE/CRG microcapsules were prepared.•The microcapsules realize the slow-release duration of OEO to over 80 h.•The microcapsules are water-soluble and capable of inhibiting B. cinerea.•The microcapsules extend the shelf life of cherry tomatoes for 8 d.