How did a thread on polymerase chain reaction lead you to a conclusion that asking this question is ok?
Help us out - I don't see any specific requirements to work with, what is wrong with freezing? What undesired result of freezing would you like to eliminate?
If you wish to preserve semen big time, then, obviously, you should look into professional methods of cryopreservation, which are actually used by people doing it for, not judging, more serious reasons than "kinda wanting to store their cum and their boyfriend's", and maybe try to replicate them in home environment.
I presume that it's not the actual sperm, its' motility etc. that you want to preserve, but the organoleptic qualities of semen. In that case, even though I have never come in contact with semen that has had been frozen, I would guess that freezing would do the trick, so, again, I do not understand the specific problem that you have.>>2684
If he were to use this semen for art, it actually would be our business - endless 'edgyfication' and bastardization of postmodernism is a problem that touches all of us.