Effect of α-tocopherol antioxidant on rheological and physicochemical properties of chitosan/zein edible films. (January 2020)

• Record Type: Journal Article
• Authors: Zhang, Liming; Liu, Zhanli; Sun, Yang; Wang, Xiaomin; Li, Ling
• Is Part Of: Lebensmittel-Wissenschaft + Technologie =. Volume 118(2020)
• Publication Date: 2020-01
• Subjects: α-Tocopherol -- Edible films -- Rheology -- Properties; Food industry and trade -- Periodicals; Food -- Composition -- Periodicals; Microbiology -- Periodicals; Nutrition -- Periodicals; 664.005
• DOI: 10.1016/j.lwt.2019.108799
• Languages: English
• ISSNs: 0023-6438

Abstract

Abstract: Edible films of chitosan/zein/α-tocopherol were fabricated by solution casting process. The effect of α-tocopherol (0 g/100 mL, 0.5 g/100 mL, 1 g/100 mL, 1.5 g/100 mL and 2.0 g/100 mL) on rheological properties, particle size and zeta potential of film-forming solutions, as well as physicochemical and structural characterization of films was investigated. Rheological properties suggested that solutions exhibited a shear-thinning and typical entangle polymers solutions behavior. G′ and G" of film-forming solutions had crossover points at the lowest frequency when the α-tocopherol concentration was 1 g/100 mL. The zeta potential increased from +26.023 to +37.187 mV, which revealed that α-tocopherol could improve the stability of solutions. The PDI decreased from 0.354 to 0.222, indicating that the film-forming solutions became uniform. The addition of α-tocopherol resulted in low water vapor permeability and excellent opacity. The lowest water vapor permeability of film was 0.944 kg m·m −2 ·s −1 ·Pa −1 and the maximum opacity of film was 12.601. It was observed that the highest value of DPPH radical scavenging was 97.66% when the α-tocopherol concentration was 1 g/100 mL. SEM images suggested that α-tocopherol exhibited better dispersion when the α-tocopherol concentration was 1 g/100 mL. The X-ray diffraction demonstrated that α-tocopherol, zein and chitosan had good compatibility. Highlights: A novel α-tocopherol/zein/chitosan film was prepared by casting. α-Tocopherol affected rheological and zeta potential of film-forming solutions. Different α-tocopherol content resulted in significantly different film properties.