Abstract: Gluten-free starch with increased total dietary fiber and methods of producing such starch are disclosed. More particularly, the starch contains less than 20 parts per million of gluten and at least 85% total dietary fiber. In some embodiments, the starch is derived from a source naturally containing gluten; in others, the starch is derived from a source which is naturally gluten-free but potentially contaminated or commingled with a gluten source. A method of making gluten-free resistant starch is disclosed, the method comprising: providing an initial starch containing a gluten protein; mixing the initial starch with water to produce an initial starch slurry; heating the starch slurry; adding an agent to dissolve or degrade the gluten protein to yield a slurry containing starch and degraded gluten protein; mixing sodium sulfate and STMP with the starch slurry; raising pH of the slurry to about pH of about 11-13; increasing heat to 115° F.