Development of equilibrium modified atmosphere packaging (EMAP) for postharvest strawberries based on material modification of permeability and selectivity: Theoretical design, model validation, and application effects

• Published in: Postharvest biology and technology 2024-05, Vol.211, p.112799, Article 112799
• Main Authors: Zhang, Yalan, Zhao, Yihui, Feng, Jing, Dong, Hao, Liao, Wenzhen, Yang, Xingfen, Chen, Sheng, He, Qi
• Format: Article
• Language: English
• Subjects: Equilibrium modified atmosphere packaging; Strawberry; Sulfonated poly ether ether ketone; Thermoplastic polyurethane
• ISSN: 0925-5214; 1873-2356
• DOI: 10.1016/j.postharvbio.2024.112799

This work aims to explore a reliable method to design and verify equilibrium modified atmosphere package (EMAP). In this work, blend films were developed using varying concentrations of thermoplastic polyurethane (TPU) as gas barrier and sulfonated poly ether ether ketone (SPEEK) as gas promoter to obtain a moderate gas permeability. A series of assays were performed to determine mechanical, hydrophilic, and barrier properties of the films. Michaelis-Menten model and atmosphere-equilibrium equation were used to theoretically deactivate the feasibility of the films as EMAP to preserve strawberries. The quality analysis of strawberries included physical attributes (mass loss, firmness, color) and chemical properties (total soluble solids, titratable acidity, malondialdehyde, ascorbic acid, total anthocyanin, total phenolics and antioxidant), verifying the freshness-keeping effects of the EMAP. As the results, the resulting EMAP provided surrounding atmospheres with 7.99 ∼ 4.45% CO2 and 3.67 ∼ 9.53% O2, that significantly inhibited respiratory rate of the strawberries, thereby delaying their ripening and freshness deterioration process during the storage. Overall, the BM25 films as packaging seem to have the best performance, as it extended the market acceptance period of the preserved strawberries from 3 days to 9 days. The overall findings indicates that this method to develop EMAP will be a promising alternative in the field of fruit and vegetable preservation. •Gas promoter was introduced in gas barrier to modify gas permeability and selectivity.•Chemical strategy for equilibrium modified atmosphere packaging (EMAP) was validated.•EMAP with varying content obtain atmospheres with 7.99 ∼ 4.45% CO2 and 3.67 ∼ 9.53% O2.•Respiratory rate of the preserved strawberries was inhibited in the EMAP.•The EMAP can maintain physical and chemical freshness of the preserved strawberries.