Active compounds from natural sources such as butterfly pea flowers (Clitoria ternatea
L.) such as anthocyanin was found able to be integrated with chitosan and Polyvinyl
Alcohol (PVA) polymers in their application as smart packaging. Smart packaging that
contains anthocyanin shows a colour response to changes in pH due to food spoilage. This
study was aimed to evaluate the effects of chitosan (CH) and PVA proportion on the
quality of biodegradable film incorporating butterfly pea flower’s anthocyanin (BPFA)
extract included film thickness, tensile strength (TS), elongation (E%), total anthocyanin
content and the film colour response at different pH range were characterized.
Concentrated anthocyanin extract was obtained from butterfly pea flower petals in
ultrasonic-assisted leaching using ethanol as a solvent and followed by rotary vacuum
evaporation. The film-forming solution was prepared from a binary mixture of CH:PVA
in the ratio of 20:80, 40:60, 60:40, and 80:20. The results showed that films obtained from
all combinations could exhibit different colour responses in various pH ranges, indicating
the successful incorporation of anthocyanin. The film with CH:PVA ratio of 40:60
showed a more pronounced colour change, among other treatments. It was also
characterized by a thickness of 0.15 mm, TS of 11.02 MPa, E% of 48.00%, and total
anthocyanin of 25.08 mg/g. The film showed high potential to be used as biodegradable
smart packaging for the food system which produces pH change upon deterioration.
Antimicrobial ZnO Nanoparticle–Doped Polyvinyl Alcohol/Pluronic Blends as Active Food Packaging Films
