I just want to address #3. If these are enzymes, the shelf life is not questionable. Most enzymes can be denatured—that is, unfolded and inactivated—by heating or chemical denaturants, which disrupt the three-dimensional structure of the protein. Depending on the enzyme, denaturation may be reversible or irreversible. This is usually done using H2SO4 and Heat. So, If I remember correctly they have to rise above 180 degrees to start this process. But I will have to take another look.