Rheological and textural properties of oleogels based on high oleic sunflower oil and a commercial emulsifier mixture.

PALLA, CAMILA ANDREA; CARRÍN, MARÍA ELENA; GENOVESE, DIEGO B.

Concordia, Entre Ríos

Conferencia; International Conference on Food Innovation - Food Innova 2014; 2014

Universidad Nacional de Entre Ríos y Universitat Politecnica de Valencia

The negative effects of trans and saturated fatty acids on human health have been well documented in the last years.  Around the world, measures are being taken to reduce their use in food preparation, compelling the scientific community to search for technological alternatives that allow obtaining products with similar physical and organoleptic characteristics but healthier for consumers. Oleogels are among some of the most promising alternatives for replacing these types of fats. An oleogel can be defined as an oil entrapped within a thermo-reversible, three-dimensional gel network. This gel network is formed by the self-assembly of a relatively low concentration of organogelator molecules. In this regard, saturated monoglycerides are especially appropriate due to their excellent capacity to self-assemble in both hydrophobic and hydrophilic domains. Once introduced in oils, these molecules are able to self-assemble into inverse bilayers leading to the formation of a continuous network preventing oil from flowing. In this work, oleogels produced with high oleic sunflower oil and a commercial emulsifier mixture (CEM) mostly composed of palmitic and stearic acids monoglycerides were studied. The effects of CEM content (6, 8 y 10%) on oil binding capacity, rheological and textural properties were evaluated. Results showed that the highest level of CEM allowed the highest oil retention. The values of elastic modulus (G') were higher than viscous modulus (G'') and almost independent of frequency, which is typical of gels. Both G' and G'' increased as the percentage of the structuring agent raised. The temperatures at onset of structure formation (or gelation) were similar for the analyzed samples, and ranged between 49 and 51 °C. The texture profile analysis (TPA) curves were used to calculate textural parameters as hardness, adhesiveness and fracturability. As the concentration of CEM increased, the three textural parameters showed a significant linear increase. In conclusion, the results obtained in this study confirmed the ability of saturated monoglycerides to structure liquid oils. However, additional characterization techniques might be necessary in order to determine tailored functionalities for specific food applications.