Effects of Cooking Temperatures on Flow Properties and Sensory Evaluations for Roux and Sauce

Abstract

The flow properties of roux prepared from wheat flour and butter at the different cooking temperatures(100°C,120°C,140°C,160°C,180°C)and the sauce made from the roux were determined by rotary viscometer at 50°C. It was revealed that each roux, remarkably uncooked mixture of wheat flour and butter, and the roux cooked to 100°C, showed non-Newtonian and time-dependent thixotropic characters. On the other hand, each sauce made from uncooked sample and the roux cooked to 100°C-140°C, showed almost same flow behavior as the roux, that is non-Newtonian and thixotropic characters, but those sauces when the materials were cooked to the temperatures of 160°C or 180°C, were gradually closing to non-thixotropic and Newtonian characters.
As the results of sensory tests for the sauces conducted by 29 female students, it was found that the taste and flavor compared with the viscosity in sensory attributes were more positively correlated with overall acceptaace in each sauce from the different roux, and the sauce from the roux cooked to 140°C, i. e. the intermediate of white and brown sauce, was evaluated most highly in the overall acceptance.