A study of gluten extractability from doughs made from fresh and stored wheat flours

In contrast to the increase in protein extractability which normally occurs in making a dough from a flour, on overmixing dough from a freshly milled flour of good bread‐baking quality, a progressive reduction occurs in the amount of acetic acid soluble proteins whereas the protein solubility shows little change in equivalent doughs made from similar flours stored for several years. Addition of artificially aged flour lipid, addition of oleic acid or defatting all tend to make the fresh flour imitate the behaviour of stored flour. Addition of diacetyl tartaric acid ester of mixed monoglyceride (which improves baking properties) to a stored flour makes the protein extractability move towards that of a fresh flour. It is suggested that in making dough from a fresh flour, there is a progressive binding of fresh flour lipid by the high molecular weight flour protein, which subsequently causes insolubility of this protein and that this binding like other lipid‐protein interactions is a major factor influencing flour baking performance.