Is double milled flour the same as 00 type flour ? I want to buy some semolina 00 type flour but I can find only double milled semolina flour ? Are they the same ?
No, double milled flour is not 00 flour. The 00 on flour is a measure of the milling fineness, this does not indicate that it has been double milled. In fact, I can find a number of sites that sell both 00 and double milled flour, such as this one (no endorsement or relationship with the company, merely one of many).
Double milled flour is flour that has been through a milling process twice. The size of the flour will be dependent on the mill size, ranging from 2-000, with 000 being the finest. Often double milling is done with a coarser size to start with and a finer size for the second mill. This produces a consistent mill and keeps the temperature in the milling process low, meaning that the proteins stay intact, so produce good gluten development.