I don't know. Try it. I'll experiment with the potato starch soon.
Basically the Nu-FLOW is organic because it is not synthetic. Silica's been used for many years for anti-caking but labs figured out how to synthesize it so it's not natural or organic. Basically both are the same. One is made in a lab, one in nature. I don't want either in my rubs. You notice they hide this and make this info hard to find. You think it's a rice product when it really is not. It's silica that is found in the ground and many plants, and they chose rice because it sounds good. Very scammy.
By the way, pick up a rub in the supermarket that has silicon dioxide in it, put some in your hand, and go out in the sun. Notice the little pieces that look like glass. I have done this.