Glycerin is glycerin. Most glycerin is a byproduct of biodiesel production. Buying vegetable glycerin is probably the easiest way to get small quantities at a high purity.
Cool. Thanks for the replies. I have seen pictures of people using bottles just marked glycerine. I wasnt too sure if they were the same. I dont want to go through all the stuff of freezing yeast and have it not work because of something like that.
Well I had already bought the glycerine yesterday. I was at Sprouts so I went ahead and picked some up just in case. If it was wrong I was just gonna return it. Looks like I got the right stuff.