Evaluation of Edible Coating Formulations with Biopolymers: A Benchmarking Approach using Mushrooms as a High Perishability Model

Abstract

Minimizing food waste and losses is essential to enhance the sustainability and resilience of the food chain. While packaging plays a vital role, traditional synthetic materials pose environmental and health risks at the end of their lifecycle. Natural polymers, particularly edible coatings formulated with polysaccharides and dispersed active agents, offer a promising alternative. However, the lack of standardization across studies hinders technology transfer and clear selection guidelines for matrices. To address this, a framework is proposed to comprehensively evaluate and benchmark biopolymers as edible coatings. Mushrooms serve as an ideal model due to their short lifespan and lack of inherent protection. Seven polysaccharides, one polyphenol, and three lipids, including underexplored options, were investigated. The proposed framework assesses weight loss and browning dynamics under various storage conditions, including refrigerated, packaged, and unpackaged settings. Pectin and sodium alginate coatings increased moisture retention by 5% in open-box storage, while lipids like beeswax and coconut oil demonstrated weight retentions of 50% and 45%, respectively, compared to the control. Sodium alginate, pectin, and cellulose derivatives significantly reduced browning (up to 10% reduction), while chitosan coatings resulted in additional browning of samples. Scanning electron microscopy elucidated the film-forming capabilities of these coatings on the porous chitinous network of mushroom surfaces. At tested concentrations, polysaccharides did not form complete films, contrasting with lipids which demonstrated complete film formation, as evidenced by their barrier properties. Water vapor permeability, UV protection, and antioxidant properties were assessed for each polysaccharide and polyphenol, while not conducted for lipids due to experimental constraints. Correlations between browning, weight loss, and other indicators isolated the coatings' impact on spoilage factors. Beyond enhancing edible coatings for mushrooms, these property relationships are expected to expedite the development of efficient formulations.

Date of Award	4 May 2024
Original language	American English
Supervisor	Blaise Tardy (Supervisor)