My dad had knee surgery recently and needed ice packs to help with the swelling. The physical therapist who came to his house told us how to make homemade ice packs, like the ones you pay $5.99 a piece for at the drug store.
2 cups water
1 cup rubbing alcohol (keeps water from freezing solid)
2 drops blue food coloring
She suggested using ziplock bags to pour the mixture in to. But because I was worried about them leaking, I used my vacuum sealer to make bags instead. I did a double seal on each end for extra assurance.
This makes a nice slushy mixture that stays cold for about an hour. Just keep them in the freezer for the inevitable bumps and bruises.
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