GlutoPeak method improvement for gluten aggregation measurement of whole wheat flour

A shear-based device, the GlutoPeak, was developed to measure the aggregation behavior of gluten. In this study, the GlutoPeak testing method was improved and applied for the gluten aggregation evaluation of whole wheat flour (WWF) of different particle size ranges. The sample/solvent weight ratio, mixing speed, and testing temperature were adjusted to different levels for obtaining more repeatable Peak Maximum Time (PMT) and Maximum Torque (MT) using two commercial WWF samples. The temperature had a greater effect on the repeatability of the PMT, while the sample/solvent weight ratio and mixing speed had lower impact on the repeatability of both PMT and MT. Another four commercial wheat samples were milled to WWFs of different particle size ranges. The gluten aggregation of the WWF was measured using the improved GlutoPeak parameters, which were 8-g WWF and 10-g 0.5 mol/L CaCl2 solvent with a mixing speed of 3000 rpm and test temperature of 20 °C. The PMT significantly decreased (with the exception of SW) and MT significantly increased with a decrease of WWF particle size. Compared to the Mixolab and Farinograph tests, the GlutoPeak method took less time and provided significantly different (p < 0.05) results for WWFs of different particle size ranges.