Fabrication and Characterization of Konjac Glucomannan/Oat ß-Glucan Composite Hydrogel: Microstructure, Physicochemical Properties and Gelation Mechanism Studies.

The aim of this study was to evaluate the effect of oat ß-glucan on the formation mechanism, microstructure and physicochemical properties of konjac glucomannan (KGM) composite hydrogel. The dynamic rheology results suggested that the addition of oat ß-glucan increased the viscoelastic modulus of the composite hydrogel, which was conducive to the formation of a stronger gel network. Gelling force experiments showed that hydrogen bonds and hydrophobic interactions participated in the formation of the gel network. Textural profile analysis results found that the amount of oat ß-glucan was positively correlated with the elasticity, cohesiveness and chewiness of the composite hydrogel. The water-holding capacity of the composite hydrogel was enhanced significantly after the addition of oat ß-glucan (p < 0.05), which was 18.3 times that of the KGM gel. The thermal stability of KGM gel was enhanced after the addition of oat ß-glucan with the increase in Tmax being approximately 30 °C. Consequently, a composite hydrogel based on KGM and oat ß-glucan was a strategy to overcome pure KGM gel shortcomings.

Quality characteristics and gastrointestinal fate of low fat emulsified sausage formulated with konjac glucomannan/oat ß-glucan composite hydrogel.

The objective of present study was to evaluate the utilization of konjac glucomannan/oat ß-glucan composite hydrogel as partial or complete fat replacer on the quality characteristics and gastrointestinal fate of emulsified sausages. The obtained results indicated that in comparison to control emulsified sausage sample, the incorporation of composite hydrogel at a 75 % fat replacement level could not only enhance emulsion stability, water holding capacity (WHC), and compact structure of formulated emulsified sausage, but also decrease their total fat content, cooking loss, hardness, and chewiness. The in vitro digestion results suggested the addition of konjac glucomannan/oat ß-glucan composite hydrogel reduced the protein digestibility of emulsified sausage, while it did not change the molecular weight of digestive products. The confocal laser scanning microscopy(CLSM) image showed the addition of composite hydrogel changed the size of fat and protein aggregate of emulsified sausage during digestion. Based on these findings, the fabrication of composite hydrogel containing konjac glucomannan and oat ß-glucan was a promising strategy as fat replacer. Furthermore, this study provided a theoretic basis for designing composite hydrogel based fat replacers.