Innovative Use of Clove Hydrosol as a Solvent for Biodegradable Quince Films

Abstract The naturally occurring mixture of polymers found in quince byproducts ( Cydonia oblonga ) allows for the fabrication of bio-based films for food applications. This work aims to take advantage of the benefits of clove hydrosol as a solvent rich in phenolic compounds and similar to water from a physicochemical point of view to produce a film based on two distinct concentrations quince-products. In the films prepared with hydrosol, catechin gallate, coumaric acid, and coniferyl aldehyde were identified as main compounds by HPLC, while eugenol was detected using GC–MS. Hydrosol-based films exhibited a total phenolic content and antioxidant activity (19.9–22.9 mg GAE/g film and 74.6–76.6%, respectively) that were approximately double those of films formulated with water (9.4–12.3 mg GAE/g film and 49.6–45.8%). Furthermore, their antifungal activity against Penicillium nordicum (15.1–16.6%) and Aspergillus jensenii (15.0-16.5%) was comparable to that of a commercial film used as a reference (19.6–20.2%). Film solutions prepared with the higher polymer concentration displayed increased viscosity (118.18 cp. and 112.30 cp., water and hydrosol respectively) and the transmittance of the resulting films was lower than those made with the less concentrated polymer (52.78 cp. and 52.80 cp., water and hydrosol respectively). FTIR and thermogravimetric analysis showed that the hydrosol does not modify the film structure. SEM confirmed a compact matrix with a crack-free surface. The integration of clove hydrosol into quince by-product films offers a promising strategy for developing functional and bioactive food packaging materials.