Soy protein isolate is most definitely something that can be home made. Assuming you have a high rev centrifuge. Otherwise you end up with soy protein that is

Soy protein isolate is most definitely something that can be home made. Assuming you have a high rev centrifuge. Otherwise you end up with soy protein that is not an isolate. Similar to purified soy flour which is already a highly processed food, and soymilk. It will still be vastly purer nutritionally than either tofu or soy. It's the same as the difference between whey protein (from milk) and whey protein isolate of various grades. Not that huge in the grand scheme of things, except for taste and amount of sugars left in it.