An intelligent delivery system for apricot preservation: pH-responsive hollow ZIF-8 loaded with lavender essential oil and its preservation efficacy

Lavender essential oil (LEO) has strong antibacterial and antioxidant properties, but its volatility limits practical use in fruit preservation. To address this limitation, we developed a pH-responsive delivery system (LEO@HZIF-8) using tannic acid (TA)-etched hollow ZIF-8 (HZIF-8) to enable controlled release of LEO. Mild etching generated a hollow structure that increased LEO encapsulation efficiency to 68.96%. Results indicate that LEO@HZIF-8 nanoparticles retain a well-defined crystalline structure and release LEO rapidly under acidic conditions, with a release rate of 73.36% at pH 4.5 after 72 h. Furthermore, LEO@HZIF-8 exhibited strong antioxidant activity, with DPPH and ABTS radical-scavenging rates of 85.48% and 78.24%, respectively, and significant antibacterial activity. When incorporated into a sodium alginate/zein (SA/Zein) coating, LEO@HZIF-8 extended the shelf life of white apricots to 63 days and effectively delayed decay, weight loss, and firmness loss. This study demonstrates an efficient pH-responsive delivery strategy for plant essential oils in freshness preservation and provides a basis for developing next-generation smart, eco-friendly active food packaging materials.