Dynamic changes of stomatal distribution, protein structural and liquor properties of oat dough during the...

Mechanistic investigation of moderate roasting on gas cell stabilization in steamed oat cakes revealed through the dynamic changes of stomatal distribution, protein structural and liquor properties of moderately gelatinized oat dough (RG50) during the fermentation process. The results showed that after fermentation for 60 min, RG50 dough exhibited retarded water mobility compared to raw oat dough (ROF), as evidenced by distinct water redistribution of ROF sample. Viscoelastic parameter decay followed exponential kinetics (Expdec1 model), with RG50 oat dough demonstrating minimal viscosity modulus reduction. Moreover, the bubbles of oat dough appeared disproportionation or coalescence phenomena, and RG50 oat dough formed relatively uniform pores in size and distribution. Considering the protein-starch network matrix of dough, the cross-linking or depolymerization of proteins in the fermentation process were in a dynamic state. Short-term fermentation primarily reduced the contents of both larger and smaller SDS-soluble polymeric protein in oat dough, whereas prolonged fermentation predominantly increased the contents of smaller monomeric proteins. Liquid phase characterization revealed that the gel-like substance rather than liquor was separated by ultracentrifugation of RG50 system after 60 min fermentation, which attributed to the high viscosity and retarded water migration of RG50 dough. Lipid redistribution in the liquid phase exhibited marked attenuation, concomitant with enhancement of foaming capacity and surface tension in ROF dough liquor as fermentation progressed.