Polyvinyl Alcohol (PVA)/Starch Bioactive Packaging Film Enriched with Antioxidants from Spent Coffee Ground and Citric Acid.

Ounkaew, Artjima; Kasemsiri, Pornnapa; Kamwilaisak, Khanita; Saengprachatanarug, Khwantri; Mongkolthanaruk, Wiyada; Souvanh, Mutjarin; Pongsa, Uraiwan; Chindaprasirt, Prinya

The bioactive packaging polyvinyl alcohol (PVA)/starch films were prepared by incorporating combined antioxidant agents i.e. extracted spent coffee ground (ex-SCG) and citric acid. Effect of citric acid content on chemical compatibility, releasing of antioxidant, antibacterial activities, and physical and mechanical properties of PVA/starch incorporated ex-SCG (PSt-E) films was studied. The results of ATR-FTIR spectra showed that antioxidant agents of ex-SCG can penetrate into the film and the ester bond of blended films by citric acid was also observed. The presence of ex-SCG increased efficiency of antioxidant release and antimicrobial activity. The PSt-E film incorporated 30 wt% citric acid showed minimum inhibitory concentration against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). The incorporation of ex-SCG and citric acid into film showed a synergistic effect on antibacterial activity. The water resistance and kinetic moisture sorption improved with incorporation of citric acid. The tensile strength and biodegradability of samples were in range of 5.63-7.44 MPa and 65.28-86.64%, respectively. Based on this study, PSt-E film incorporated 30 wt% citric acid can be applied as novel food packaging materials.

POLYVINYL alcohol; BIOACTIVE compounds; STARCH; ANTIOXIDANTS; COFFEE grounds; CITRIC acid

Journal of Polymers & the Environment, 2018, Vol 26, Issue 9, p3762

1566-2543

Academic Journal

10.1007/s10924-018-1254-z