How to Make "Blue Ice"!
You might already own some "blue ice" or some kind of ice pack/freezer pack/gel pack
to place in your cooler to keep you food cold. Now you no longer need to buy them.
You can make your own freezer pack at home!
Making “Blue Ice”
After doing many “ice cream” demos and answering lots of questions about how the salt & ice serves to freeze the ice cream, something dawned on me... I could make my own freezer packs!
Traditional ice cream makers use salt and ice in the process of freezing the ice cream. The salt lowers the freezing point of water and actually melts ice. At the same time, it draws heat away from the ice cream canister, allowing the mix inside to freeze. What dawned on me is that I could add salt to water, then freeze it, and this should be colder and last longer than the same container filled with regular water. I replaced the water with salt water in some of my containers and did a test using two separate coolers. The one with the salt ice did get colder and the cooler stayed cold longer! At one class where I was a guest chef, I had prepared some fresh coconut water and had it in a glass jar. I took the chilled jar and put it in my cooler with the salt ice jugs. At the demo, I pulled out the coconut water to find it had started to freeze! It was crystallizing in my cooler! I’ve now been using my salt water ice for many years. I have several different sized jugs.
Rock Salt (aka Ice Cream Salt) (Available at many grocery stores. Check the baking section.)
Warm to hot Water
Sealable containers, such as plastic jugs: quart, half gallon, or gallon
(You could even try Zip-Lock bags)
Add ¼ cup rock salt per 1-quart warm water in a jug (leave room for the ice to expand). Mix or shake until dissolved. Place in your freezer until frozen. Use as needed!
The proportions of salt to water that I use:
¼ cup per quart container
½ cup per ½ gallon container
1 cup per gallon container
(If you really feel a need to have your freezer pack to be blue (or some other color), feel free to use a food-safe coloring (in case it leaks onto your food!).
Please note: Containers occasionally leak salt powder. You may need to recharge/replace the salt water in the containers periodically.
Cooler stays colder and for longer
No more water from melted ice (though you can also have ice in the cooler which may be kept from melting)
Reusing jugs and bottles, etc. instead of recycling
You know exactly what’s in it, environmentally safe salt and water, no mysterious colors or chemicals
Save money by not buying pre-made cooler packs/ice packs