Effects of gelatinization degree and boiling water kneading on the rheology characteristics of gluten-free oat dough

The effects of gelatinization degree of oat flour and boiling water on the rheological characteristics of oat dough were investigated. Gelatinized oat flour had higher water absorption (2.25-3.83 g/g) and swelling (2.40-4.19), but lower solubility (6.20-8.60 %) at 25 °C. Oat dough gradually developed a honeycomb-like structure with the increase of gelatinization degree. Gelatinization treatment and boiling water kneading increased bound water content (9.39-12.89 %) and enhanced the elastic behavior of oat dough, with moderate G', lower tan δ, and higher relative elastic portion (77.40 %) and stress relaxation percentage (34.55 %) in the dough prepared by 50 % or 65 % gelatinized oat flour. Chemical interactions showed hydrogen bond and covalent bond were the main interactions in oat dough made from moderately gelatinized oat flour. Moderately gelatinization and boiling water kneading could modify the rheological characteristics and improve the texture and processing adaptability (lower adhesiveness) of oat dough.