Empirical and Fundamental Rheological Properties of Wheat Flour Dough as Affected by Different Climatic Conditions

Abstract

The aim of this study was to evaluate the capability of the empirical (large scale) and fundamental (small scale) rheological tests to differentiate between wheat flours of different harvest years. In order to provide flours affected by different climatic conditions, harvest years 2004 and 2005 characterized by high temperatures and large amounts of rainfall were chosen. Moreover, a control wheat flour sample was also tested. In order to simulate the baking process, both rheological measurements at constant low temperatures (30°C) and those that involved heating (30-100°C) were employed. Empirical and fundamental rheological parameters related to gluten strength were in great accordance and the flour strength decreased in the following order: control wheat flour> wheat flour of 2005> wheat flour of 2004. However, parameters related to starch pasting, such as peak viscosity, expressed different order when measured in suspension (Amylograph, Falling number) and dough (Mixolab, Rheometer) due to different amounts of available water. Keywords: Climatic conditions, Harvest year, Rheology, Wheat flour.