Microwave pretreatment enhanced the properties of ovalbumin-inulin-oil emulsion gels and improved the storage stability of pomegranate seed oil

The present study constructed a new gellable emulsion with the aid of microwave pretreatment to encapsulate pomegranate seed oil (PSO). The results showed that ovalbumin (OVA), inulin (IN) and carrageenan (kappa-car) were adsorbed on the PSO drop surface to form an OVA-IN-PSO emulsion, and then, gelation of the emulsion occurred by heating with the assistance of microwave pretreatment. The properties of the OVA-IN-PSO emulsion gel, including the water holding capacity, fixed water ratio, texture properties, and rheological properties, were improved by microwave pretreatment. Microscopic observation confirmed that the OVA-IN-PSO gel was an oilin-water type with a dense structure. Moreover, the denaturation temperature of the OVA-IN-PSO emulsion increased from 70.7 degrees C (0 min) to 76.3 degrees C (10 min). Benefitting from the protective effect of the OVA-IN-PSO gel, the stability of pomegranate seed oil was significantly improved. Lipid oxidation (peroxide value) and the loss of polyunsaturated fatty acids during pomegranate seed oil storage were suppressed. These results suggested that microwave pretreatment can improve the properties of OVA-IN-P SO gel as well as the oxidation stability of pomegranate seed oil.