Clove Oil Loaded in Modified Zirconium MOF Extends Fruit Shelf Life in Starch Films

A biodegradable packaging film that slowly releases clove essential oil has shown the ability to keep blueberries and green grapes fresher for longer, according to a peer-reviewed study published on 27 October 2026 in Discover Food. The work is being shared as an early-access article, meaning it is citable and carries a permanent DOI but remains subject to further edits before the final version of record appears.

The researchers, led by Kang Zhang, Huan Zhang and Hefeng Zhu with colleagues including Yixiu Wang, built their system around a zirconium-based metal-organic framework. They modified NH2-UiO-66 with glycidyl methacrylate, or GMA, to create a porous carrier for clove essential oil, a volatile antimicrobial. The modified carrier achieved a loading capacity of 780.3 ± 6.5 mg of oil per gram, a figure the authors describe as high. Structural characterization confirmed successful GMA functionalization, encapsulation of the oil, stability of the carrier material, and good integration of the active filler within the starch matrix.

The loaded particles were then incorporated into films made of starch and gellan gum at concentrations ranging from 0.5 to 4 wt% based on the combined mass of the two polymers. The film containing 2 wt% of the oil-loaded carrier performed best in mechanical and barrier testing. It recorded a tensile strength of 23.8 ± 0.9 MPa, an elastic modulus of 315.3 ± 15.9 MPa, and an oxygen transmission rate of 30.7 ± 1.36 g·d⁻¹·m⁻².

Release of the essential oil from the composite film followed the Avrami model, with a coefficient of determination of 0.9992, which the authors say confirms controlled-release behavior.

In fruit preservation tests over 9 days, the active film reduced mass loss in blueberries from 38.5% to 18.3% and maintained the visual quality of both blueberries and green grapes. The authors conclude that CEO@GMA-NH2-UiO-66 is a promising additive for starch-based active packaging films aimed at fruit preservation. As with any materials study conducted at laboratory scale, the reported mechanical, release and preservation results reflect the specific film formulations and test conditions described, and the findings concern the tested fruits and storage period rather than broader commercial performance.

Subject of Research: Controlled release of clove essential oil from a modified zirconium metal-organic framework in starch-based films for fruit preservation.

Article Title: Starch-based controlled release packaging films for fruit preservation via clove oil loaded in modified MOF(Zr)

Article References: Zhang, K., Zhang, H., Zhu, H., Wei, Y., He, Y., & Wang, Y. (2026). Starch-based controlled release packaging films for fruit preservation via clove oil loaded in modified MOF(Zr). Discover Food. https://doi.org/10.1007/s44187-026-01313-0

Image Credits: AI Generated

DOI: 10.1007/s44187-026-01313-0

Keywords: clove essential oil, metal-organic framework, NH2-UiO-66, starch films, gellan gum, active packaging, controlled release, fruit preservation, blueberries, green grapes, biodegradable packaging, antimicrobial packaging