Mechanical properties of ethylcellulose oleogels and their potential for saturated fat reduction in frankfurters

Abstract

Ethylcellulose has been recently shown to be an excellent organogelator for vegetable oils. The resulting gels maintain the fatty acid profile of the vegetable oil used, but posses a solid-like structure that can be useful for the replacement of saturated fats in food products. Texture profile analysis and the back extrusion technique were used to assess the mechanical properties of canola, soybean, and flaxseed oil oleogels consisting of 10% ethylcellulose and 90% vegetable oil. Oils with a higher degree of unsaturation were shown to produce harder gels. Oleogels containing ethylcellulose of three molecular weights and reduced polymer concentrations from 4–10% ethylcellulose were also tested using the back extrusion technique, resulting in an increase in gel strength as polymer concentration and molecular weight increased. Therefore, oleogel strength was shown to be dependant on polymer molecular weight, concentration, and the fatty acid composition of the vegetable oil. Scanning electron microscopy was also used to provide a greater understanding of the gel's microstructure. In addition, frankfurters were made using canola oil oleogels to assess the possibility for replacement of the more highly saturated animal fat in such a product. Cooked frankfurters made with oleogels showed no significant differences in chewiness or hardness compared to the control products made with beef fat. These results provide the first in-depth characterization of ethylcellulose oleogels, and could potentially aid in the design/manufacture of ethylcellulose oleogels with specific textural properties to replace saturated fat in a variety of food products.