Pectins extracted from cranberry pomace: A study in physicochemical, structural, functional properties and the application in peach preservation

Cranberry pomace was utilized to extract pectins using various methods (water, oxalic acid, and natural deep eutectic solvent (NADES)) with or without ultrasound assistance. Ultrasound-assisted NADES extraction (US-NCPP) yielded the highest pectin content (5.53 %) and the highest galacturonic acid (GalA) content (83.20 %), indicating superior purity. US-NCPP also exhibited outstanding antioxidant activity, with the lowest IC₅₀ values for both ABTS (0.55 mg/mL) and DPPH (0.21 mg/mL) radical scavenging. The degree of esterification (DE) and FTIR analysis revealed that all pectins were high-methoxyl (DE: 71.58-85.21 %). Furthermore, an edible film fabricated from US-NCPP significantly enhanced the postharvest quality of peach fruit during an 8-day storage period. Compared to the control, the film extended the shelf life of peach samples from 4 d to 8 d at room temperature. These findings demonstrate that US-NCPP is a highly effective strategy for obtaining high-quality, antioxidant-rich pectin from cranberry pomace, which shows great potential as a bioactive film for fruit preservation.