Relative contribution of wheat flour constituents to Solvent Retention Capacity profiles of European wheats

Abstract

Solvent Retention Capacity (SRC) tests have originally been designed to predict flour functionality of North American wheat flours. A SRC profile consists of its Water Retention Capacity (WRC), Sodium Carbonate SRC (SCSRC), Sucrose SRC (SuSRC) and Lactic Acid SRC (LASRC) values. As the value of such tests when considering European wheat flours is rather unclear, we studied the chemical composition and SRC profiles of nineteen commercial European wheat flours. Their WRC, SCSRC, SuSRC and LASRC ranged from 56 to 66%, 74 to 88%, 90 to 102% and 106 to 147%, respectively. Both WRC and SCSRC were mostly higher than those of North American soft wheat flours, but in the range of those of North American hard wheat flours. For the entire set of European flours, strong linear relations were observed between the flour damaged starch levels and WRC values, as well as with SCSRC values. Modifying specific flour constituent properties and levels illustrated the contribution of proteins, damaged starch and arabinoxylan (AX) to the SRC values. Flour proteins, especially glutenins, mainly contributed to LASRC, while damaged starch largely impacted flour SCSRC. Water-extractable AX only contributed to the SuSRC values, whereas the solvent-accessible AX generally contributed to all SRC values, and particularly to the SuSRC values.