Thermo-irreversible emulsion gels based on deacetylated konjac glucomannan and methylcellulose as animal fat analogs

Abstract

As animal-fat analogs, polysaccharide-emulsion gels with different ratio of methylcellulose (MC) to deacetylated konjac glucomannan (DKG) ratios (DKG:MC = 2:8–8:2) were prepared using two different oils (canola (Ca) and coconut oil (Co)). The emulsion gels (Ca-EG and Co-EG) were thermo-irreversible and thermo-stable at 80 °C, irrespective of the DKG:MC ratio, owing to the dominant thermo-gelling properties of MC. At 20 °C, the texture profiles and viscoelasticity were dependent on the DKG:MC ratio, which impact the molecular interactions (hydrogen bonds). The components of the emulsion gels exhibited a synergistic effect on gelation over a wide temperature range. The Co-EG exhibited enhanced gel strength and stability. The emulsion gels provided lower energy than pork back fat (p < 0.05) and higher stability against oxidation during refrigerated storage at 4 °C for 28 d. As a new fat analog system, this thermo-irreversible emulsion gel has potential utility in the plant-based food industry.