Making my own hydrolyzed vegetable (soy) protein?

I can't have alcohol, wheat, or anything that has been fermented with fungus. So, most soy sauce is out of the question. I came across some hydrolyzed soy protein, though, and I was wondering if I can make my own. The problem is that I need to boil the soy beans in hydrochloric acid, and I haven't been able to find any for sell. Would Betaine HCL work? What about Glucosamine Hydrochloride? Other than that, can I just use baking soda to neutralize it? Thanks!