Considerable interest has emerged in developing biodegradable food packaging materials derived from polysaccharides. Phenolic compounds serve as natural bioactive substances with a range of functional properties. Various phenolic compounds have been incorporated into polysaccharide-based films and coatings for food packaging, thereby enhancing product shelf life by mitigating quality degradation due to oxidation and microbial growth. This review offers a comprehensive overview of the current state of polysaccharide-based active films and coatings enriched with phenolic compounds for preserving fruits and vegetables. The different approaches for the addition of phenols to polysaccharides-based packaging materials are discussed. The modifications in film properties resulting from incorporating polyphenols are systematically characterized. Then, the application of these composite materials as protectants and intelligent packaging in fruit and vegetables preservation is highlighted. In future, several points, such as the preservative mechanism, safety evaluation, and combination with other techniques along the whole supply chain could be considered to design polyphenol–polysaccharides packaging more in line with actual production needs.
Functionalized edible coatings represent a promising strategy to mitigate postharvest losses in fresh and fresh-cut fruits. This study developed a novel, ternary active coating by integrating pectin with a cationic antimicrobial polypeptide (ε-polylysine) and a hydrophobic plant flavonoid (luteolin). The resulting composite film demonstrated transformative improvements in hydrophobicity, antioxidant, and antimicrobial activities as compared with conventional pectin-based films. Specially, the ternary composite film exhibited enhanced barrier performance, reducing water vapor, oxygen and carbon dioxide permeability by 49.1%, 68.6%, and 26.5%, respectively. When applied to fresh-cut apples, the coating effectively suppressed the browning and microbial proliferation while maintaining the hardness, total phenols and flavonoids, total soluble solids, and titratable acids over a 12-day refrigerated storage period. Comprehensive characterization via Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), and molecular docking simulations revealed that these superior functionalities originate from synergistic electrostatic interactions and hydrogen-bonding networks within the ternary matrix. This work provides a practical strategy for designing high-performance, plant-based coatings to reduce food waste and improve the quality of fresh-cut produce.
Blueberries are widely consumed due to their richness in nutrients, yet they are also prone to quality deterioration after being harvested, even at cold temperatures. Non-thermal physical technology is an important auxiliary method worth considering for maintaining the quality of this fruit while refrigerated. In this study, a static magnetic field (SMF) was applied as a complementary pretreatment strategy prior to cold storage of blueberries. The optimal SMF parameters were identified as 5 mT exposure for 12 h, as this significantly retarded decay and softening. The contents of ascorbic acid, total polyphenols, flavonoids and proanthocyanidins were elevated by 20.0%, 17.7%, 23.9%, and 9.1%, respectively. Concurrently, DPPH (1,1-diphenyl-2-picrylhydrazyl) radical-scavenging capacity, catalase (CAT), and superoxide dismutase (SOD) activity markedly improved. Targeted metabolomic analysis revealed that SMF pretreatment significantly regulated polyphenol metabolic pathways and redirected polyphenol biosynthesis toward more stable and functional compounds, including three hydroxycinnamic acids, quercetin, dihydromyricetin, glycosylated hesperetin, and acylated delphinidin derivates. The synergistic effect of these SMF-elevated phenolics and the reinforced antioxidant system preserved the overall cold-storage quality of blueberries. These findings underscore the potential of SMF pretreatment as an effective physical technique for reducing postharvest blueberry losses.