Changes in microstructure and rheological properties of konjac glucomannan/zein blend film-forming solution during drying. (15th December 2020)

• Record Type: Journal Article
• Authors: Li, Chong; Xiang, Fei; Wu, Kao; Jiang, Fatang; Ni, Xuewen
• Is Part Of: Carbohydrate polymers. Volume 250(2020)
• Publication Date: 2020-12-15
• Subjects: Film-forming process -- Microstructure -- Rheology -- Konjac glucomannan -- Zein; Polysaccharides -- Periodicals; Polysaccharides -- Periodicals; Polysaccharides -- Périodiques; Electronic journals; 547.78
• DOI: 10.1016/j.carbpol.2020.116840
• Languages: English
• ISSNs: 0144-8617

Abstract

Highlights: Zein promoted the aggregation of KGM chains in KGM/zein blend solution. Zein particles grew larger but were homogeneously distributed during drying. KGM/zein blend solution gradually formed a weak gel after 2 h of drying at 60 °C. Abstract: During film formation at 60 °C, the microstructure and rheological properties of konjac glucomannan (KGM) film-forming solution and KGM/zein blend film-forming solution were investigated. The drying process of film-forming solutions was divided into two stages according to the drying curves. Scanning electron microscopy showed that KGM chains in the blend solution aggregated into thicker chains and formed a molecular network with larger pores. Zein particles grew larger but were homogeneously distributed during drying as observed by confocal laser scanning microscopy. The addition of zein improved the thermal stability of the film-forming solution. As the drying proceeded (up to 8 h), KGM solution exhibited a typical concentrated solution behavior due to molecular entanglement; whereas the blend solution gradually formed a weak gel after 2 h. Complex viscosity data for the film-forming solutions were well-fitted by the power-law model. The information obtained from the study is important for understanding the film-forming mechanism.