Changes in protein structural characteristics upon processing of gluten-free millet pasta

•Proso millet pasta displayed differences to commercial gluten-free and wheat pasta.•Cooked millet pasta had low protein solubility and high β-sheet content.•Millet protein profile and conformation affected functional properties of the pasta.•Protein solubility correlated with digestibility and cooking loss of millet pasta. Proso millet exhibits favorable agronomic and nutritional properties but is currently under-utilized in the northern hemisphere. This study compared processing-induced changes in protein characteristics of commercial pasta to fresh gluten-free pasta from proso millet varieties differing in prolamin profile. Protein solubility, accessible thiols and secondary structures were measured in dough, sheeted and cooked pasta. Relationships between protein conformation and characteristics related to pasta quality were determined. Cooking significantly lowered protein solubility and induced exposure of thiol groups as well as a shift in secondary structure distribution, while sheeting only had a minor effect. Random structures positively and significantly (P