In the wake of a decision by Nestle USA to heat treat the flour used in its Toll House refrigerated cookie dough, milling companies have received a surge of inquiries about heat treating flour and the microbial content of milled products. Bakers and most other users of flour who may be thinking about shifting to heat-treated flour should think twice.
While ideal for specialty uses like altering the properties of flour for gravies and sauces, heat treatment has little to offer bakers. To the contrary, the process is unnecessary (baking provides a kill stage for microbes that may be in flour), may adversely affect the functional properties of flour, and is costly (estimated at $8 to $12 per hundredweight).
Heat treatment certainly may be appropriate for certain flour uses, including refrigerated cookie dough (though many would argue against this point), dehydrated infant foods and spice coatings for snack chips and other uses. There is little question but that bakers and flour millers will need to spend more in the years ahead on sanitation given the mounting concerns about food safety. This spending should be done wisely. For far more than 90% of the flour milled in the United States, heat treatment would not qualify for this descriptor.