Fabrication of edible gellan gum/soy protein ionic-covalent entanglement gels with diverse mechanical and oral processing properties

A sequential ionic-covalent gelation method for fabricating double network structure in an edible polysaccharide/protein gel was demonstrated in this work. Gellan gum and soy protein isolate (SPI) with the cross-linkers KCl and microbial transglutaminase (MTGase) were used to prepare the ionic-covalent entanglement (ICE) gel. Time sweep dynamic rheological analysis confirmed that gellan gum and SPI formed separate gel network one after another during gel preparation. Scanning electron microscopy (SEM) observation revealed that the two hydrocolloids participated in the formation of the gel networks. The uniaxial compression measurements indicated that the double network system combined the structural and mechanical characteristics of the gellan gum and SPI networks. The oral processing properties including muscle activities and jaw movements during chewing the ICE gels were investigated. The ICE gels with distinctive mechanical and oral processing properties were prepared by regulating the composition ratios of polysaccharide to protein. With this preparation strategy, polysaccharide/protein edible gels that provided various texture perceptions could be fabricated. (C) 2014 Elsevier Ltd. All rights reserved,