Just like I'd be concerened if my blood or pee was cold.. not that I ever feel my own pee too often lol but you get the point.
OP just keep your other hand out from under your blankie till you're ready to catch it and you should be able to lay this whole thing to rest. Or if you're lucky, get someone to swallow so it never hits air temp. They will be able to tell you if it was a cool drink.
Since the sperm is created outside the body, in the testicles, it is not always warm or hot, from my experience. Once you get aroused, the sperm travels up the spermatic cords to the prostate, which is a donut -shaped organ around the base of the bladder inside the body, where it mixes with the semen and then is ejaculated down the urethra and out. I would think that if you have a quick orgasm, it could well be somewhat cold when ejaculated, but if you "edge" for a long time and keep the sperm/semen mixture in the prostate for a long time before ejaculating, or have extended intercourse before ejaculating, it could come out hot or warm.
^Thanks for the suggestion. I usually don't have time to do that but I'll try it this weekend and see the results...