I have asked a friend about this in the past. He was an absolute coffee fiend. He has now given it up and drinks more booze instead (citing its less disruptive to his life).
I remember his tip when I asked him about taking coffee on a long hike.....
"I have in the past made lots of shots of espresso (or espresso corto) with a robust bean, place the shots in a 500ml PET bottle - half fill it. That will be about 10shots (250ml). I make sure I then pop it straight into the freezer (the coffee can oxidize very quickly and degrade once made). Once frozen I can either wrap it and pack it. Its good for a couple of days. Or freeze it, partially thaw it, pour off excess water (to concentrate it even more) then 3/4 fill film containers and freeze the crude oil thick coffee concentrate. I then have a rocket-fuel when I need it - in easy use containers. Just add hot water!
Please note: this coffee can wake the dead."
I have not actually tried it. But he was a bit of pro....so I hope he was not full of