Effect of the Hofmeister series on gluten aggregation measured using a high shear-based technique

This study investigated differences in gluten aggregation time and gluten strength using the Hofmeister series in high shear-treated slurries. Two flours (15.1% and 10.6% protein) were evaluated by using a Gluten Peak Tester (GPT). Hofmeister anions including NaF, NaCl, NaBr, NaI, and NaSCN at concentrations ranging from 0.1 to 1.0 M and cations including KCl, NaCl, NH4Cl, MgCl2, and CaCl2 at concentrations ranging from 0.0625 to 1.0 M were used. The instrument applies high shear to a flour/salt solution slurry and measures torque and aggregation time to form gluten. Aggregation time using the GPT followed the order of the Hofmeister series, with minor effects at salt concentration < 0.3 M and increasing differences at higher salt concentrations. Torque increased with increasing concentration. Creating models of the trends using second and third order equations demonstrated that gluten aggregation follows a distinct natural law in the slurries. The study confirmed the potential of the high shear based method to be used a research tool to investigate gluten aggregation properties and to potentially predict functionality in baked product systems.