You can try this. Heat a cup of water to almost boiling ( about tea or hot coffee temp. ). When its really hot and steamy, put the tinture in it. Wait about 5 minutes or so. Almost all the alcohol will evaporate. You can get another person to taste test it for you. My experience has been if the water is hot enough ( almost boiling and steam coming off ), I can taste no alcohol once the tinture has been in it about 5 minutes. A chiropractor taught me this trick.
Another alternative would be to get the dry components of the herbs you want to use and make tea. This is more work though.
Also, gaia herbs does sell Black-Walnut and some other herbs in an alcohol free tinture.