Effect of tea polysaccharide conjugates combined with different phenolic compounds (EGCG/EGC/TP) on tomato preservation through composite film formation.

Postharvest physiological deterioration causes significant global produce loss. This study developed ternary composite films using tea polysaccharide conjugates (TPC), tea polyphenols (TP)/EGCG/EGC, and glycerol via solution casting. The impact of polyphenol composition on film properties and tomato preservation efficacy was investigated. Optimized films (TPC 0.3 g; glycerol 0.25 g; TP 0.5 g/EGC 0.3 g/EGCG 0.4 g) demonstrated increases of ∼175 % in tensile strength and ∼ 388 % in elongation at break relative to TPC-only films. FT-IR and SEM analyses confirmed strong hydrogen bonding between polyphenols and TPC, enhancing structural integrity. Coated tomatoes exhibited 10-40 % lower weight loss after 15 days storage, alongside significantly better maintenance of chromatic aberration (ΔE) and total soluble solids versus controls. Polyphenol-polysaccharide synergy achieved concurrent antioxidant, antimicrobial, and quality preservation effects, offering a sustainable strategy utilizing tea byproducts for packaging.