Rheological and sensory characteristics of yoghurt-modified mayonnaise

Rheological and textural characteristics were studied in a set of 11 samples of yoghurt-modified mayonnaise at 15, 20, and 25 deg C. The rheometer Rheostress 300 was used to determine the static yield value, apparent viscosity, thixotropy, and elasticity. The sensory texture and flavour profiles were developed and determined in agreement with the respective international standards, using a group of selected and trained assessors. The yield value and apparent viscosity substantially decreased with increasing temperature, but thixotropy and sensory characteristics were not significantly affected. Linear and semilogarithmic relations were observed between the variables, but more complex relations, showing a maximum or a minimum, were found in some cases. Thixotropy was related to most of the sensory variables, viscosity was related to spreadability, and significant relationships existed between the texture acceptability and the flavour acceptability. Rheological measurements were thus useful for a rapid prediction of the sensory properties of yoghurt-modified mayonnaises, but could not be used to replace any textural analysis.