Mayonnaises are oil in water emulsions with a texture that is particularly appreciated by consumers. The actual nutritional trend towards low-calorie foods has increased the interest in fat substitutes without altering the consistency of the product. From this point of view rheological properties may give a quantitative contribution to texture characterization and control when using different formulations. The rheological approach has been applied to typical commercial normal and light mayonnaises with a fat content ranging from 76 to 48%. These materials have shown a viscoelastic behaviour that was measured by means of both oscillatory and creep-recovery tests. The storage modulus, the compliance and rite yield stress were found to increase when increasing the fat content A modified Bolhin theory was used to relate structural parameters to rheological dynamical measurements. Thus the emulsion stability was quantified by means of a pseudoplastic-coordination number (z) and the value of G＇ at 1 Hz. From the creep test the value of the yield stress was determined and in the case of the light mayonnaise was very close to a normal emulsion whereas the corresponding viscoelastic properties were very different. This implies that to reproduce an assumed texture, it is necessary to perform all the tests outlined