My dad used to take a couple of those "Desert Bags" canteens along for our road trips. After he soaked them in water and filled them with water he would hang them off the front of the station wagon. When we got to our first jumping off point he'd give us one to drink from. Man that water was cold! even though it was 80 degrees out, that water was cold.

I have bagged meat and dipped them into creeks before and the evaporation has kept the meat from spoiling.I have put said dipped bags of meat in plastic bags and the meat warmed up a bit to the point where I didn't trust it. The meat began to spoil.

If you are boning an animal and putting the meat into game bags I would recommend double layering the bags. Blow flys and such have to search real hard to find a way to the meat. Two bags retain the cooling effect longer.

If you have to spend the night hang your bags high to keep predators from getting to them. Hang the meat far enough away from camp to keep the predators from getting at you. The temps in the mountains at night should sustain the cooling effects and help preserve the meat. And on your trip out you can dip the bags in a stream (if there is one near) to keep the meat cooling until you get to a processor or a place where you can better care for your trophy.

That's my experience good luck hunting best of all.