Active and intelligent gellan gum-based packaging films for controlling anthocyanins release and monitoring food freshness

• Published in: Carbohydrate polymers 2021-02, Vol.254, p.117410-117410, Article 117410
• Main Authors: Wu, Li-Ting, Tsai, I-Lin, Ho, Yi-Cheng, Hang, Yu-Hao, Lin, Chi, Tsai, Min-Lang, Mi, Fwu-Long
• Format: Article
• Language: English
• Subjects: Active film; Anthocyanins - chemistry; Antimicrobial; Clitoria - chemistry; Color; Colorimetric pH indicator; Colorimetry - methods; Controlled release; Food Packaging - methods; Food Quality; Gellan gum; Hydrogen-Ion Concentration; Indicators and Reagents; Intelligent packaging; Permeability; Plant Extracts - chemistry; Polysaccharides, Bacterial - chemistry; Seafood; Smart Materials - chemistry; Soybean Proteins - chemistry; Static Electricity; Steam; Tensile Strength
• ISSN: 0144-8617; 1879-1344
• DOI: 10.1016/j.carbpol.2020.117410

•Active and intelligent films prepared from gellan gum and Clitoria ternatea extract.•Antioxidant, antimicrobial and colorimetric pH indicator properties of the films.•Gellan gum enhancs the stability and controls the release of CT anthocyanins.•Soy protein affects physical and mechanical properties and anthocyanins release rates.•The pH indicator films change their colors in response to seafood spoilage. Active and intelligent packaging films with multiple functions including antioxidant, antibacterial and colorimetric pH indicator properties were developed by incorporating Clitoria ternatea (CT) extract into gellan gum (G) film. G enhanced the stability of CT anthocyanins and allowed the anthocyanins to release from G film in a pH-responsive behavior. Heat-treated soy protein isolate (HSPI) was able to interact with G and CT anthocyanins through the formation of electrostatic forces and covalent bonds. G film blended with HSPI greatly reduced the swelling capacity of G/HSPI composite film and controlled the anthocyanins release at pH greater than 6.0. The physical and mechanical properties of G films such as hydrophobicity, water vapor permeability, swelling capacity and tensile strength were also significantly modified by addition of HSPI to G films. The smart films changed their color with the increase of total volatile basic nitrogen (TVBN) values during progressive spoilage of shrimp, revealing their potential application for monitoring seafood freshness.