To help foods stay frozen in your ice chest, freeze a brine solution in a reusable container and place it into the chest. A frozen brine solution is slower to melt than ice and will keep food frozen longer.
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This can be used to keep harvested meat cool on the way back from a hunt.
Also, this can be used if you want some additional help in a home chest-freezer in case of an extended power outage.

Keep Your Cooler, Cooler!
To help foods stay frozen in your ice chest, freeze a brine solution in a reusable container and place it into the chest. A frozen brine solution is slower to melt than ice and will keep food frozen longer.Fill a clean milk jug with water, leaving about 1" of space for expansion. Add 1/4

This can be used to keep harvested meat cool on the way back from a hunt.
Also, this can be used if you want some additional help in a home chest-freezer in case of an extended power outage.