Preparation And Application Of Regenerated Cellulose Emulsion

Dietary fiber extracted from plants has been widely applied into meat products to reduce the fat content,improve the rheological properties and emulsion stability.Microcrystalline cellulose(MCC)can be added to various foods as anti-caking agents,thickeners and stabilizers without restrictions,such as application in breads for texture improver,milk drinks for thickener and stablilizer,seasonings for fat substitute.The fiber in previous studies in the form of insolubility attributing to the strong intermolecular hydrogen bonds may cause an imbalanced distribution and lead to the feeling of coarse mouth feel of products.MCC dealted with acid dissolution and water regeneration could be distributed properly in food system.The present study focus on the effects of regenerated cellulose on stability of SC stabilized emulsion,aiming at determining a stable emulsion with proper RC.Then properties of RC emulsion as a whole to be applied into myofibrillar protein gel and emulsified sausage production were investigated.The main contents and results are as follows:1.Effects of RC on stability of SC emulsified soybean oilThis study focused on the addition of RC(0%,0.5%,1.0%,1.5%,2.0%)on the apparent stability,creaming index,particle size and distribution,and rheological properties and microstructure of emulsion during storage time(1 d,7 d).The results showed that emulsions stabilized by Na-SC was concentration dependent,with 1.5%RC being the critical concentration with slight flocculation,a smaller droplet size and a stronger gel network.During the storage time,particle size and zero shear viscosity of emulsion was significantly increased(P<0.05).The frequency sweep showed the occurrence of flocculation and coalescence during storage,emulsion existed the strongest gel structure with 1.5%RC;in the same storage time,the emulsion particle size increased and then decreased with increasing RC,the emulsion particle size and flocculation degree were significantly lower than other groups with 1.5%RC(P<0.05).The viscosity of emulsion with RC addition group was higher than the control.Microstructure showed uniform distribution of the RC in the continuous phase,while SC adsorbed on the surface of the droplet,RC increased the viscosity of the emulsion by thickening,increasing the adsorption of SC on the surface to limit the movement of droplets.Therefore,the incorporation of 1.5%RC reduced the particle size,increased the viscosity and improved stability of the emulsion.2.Effects of RC emulsion on porcine myofibrillar protein gel propertiesThe rheological properties,texture,water retention and microstructure were investigated with RC emulsion(0%,7.5%,15%,22.5%,30%)incorporated into myofibrillar protein(6%)composite gel system.The results showed that the addition of RC emulsion significantly improved water holding capacity and texture characteristics(P<0.05).The cohesiveness of composite gel was optimum with 15%RC emulsion.Microstructure showed the proper amount of RC emulsion(15%)could be uniformly filled into the gap of myofibrillar protein network.Therefore,RC emulsion could effectively improve functional properties of composite emulsion gel.3.Effects of RC emulsion on qualities of emulsified sausageEffects of RC emulsion as substitute of pork back fat(25%,50%,75%and 100%)on chemical composition,texture,rheology,fatty acid profile,lipid oxidation and sensory properties of emulsified sausage were evaluated.The results showed that moisture content and protein content increased significantly(P<0.05)with the increased substitution degree and fat content decreased significantly(P<0.05).There were no significant difference in hardness and elasticity between treatments with RC emulsion(P>0.05),while both were significantly higher than the control without the addition of RC(P<0.05).Cohesiveness tended to increase and reached the highest value when 50%fat was substituted with RC emulsion.With the increase of RC emulsion,the SFA,MUFA and n-6/n-3 was significantly reduced(P<0.05),while PUFA content,PUFA/SFA increased significantly(P<0.05).Lipid oxidation was aggravated during storage time and the oxidation degree increased and later decreased significantly with the enhancement of RC emulsion at the same storage time(P<0.05).Sensory evaluation indicated reduced score of appearance with RC emulsion above 50%and hardness and juiciness obtained the highest scores at 50%substitution degree.There were no significant differences in flavor and overall acceptability(P>0.05).Therefore,RC emulsion could effectively reduce the fat and SFA contents and improve the textural properties,PUFA and oxidation stability.