PROJECT 45

PLASTIC BAG ICE CREAM INSERT

This is a fun way to both spend time with your family, enjoy a nice summer treat, and experiment with cold in a fun way.

Just be sure to double bag the milk and ensure everything is closed nice and tight.

Each recipe makes a single serving—you can eat it straight from the bag.

Ingredients:

•   ½ cup milk

•   ½ teaspoon vanilla

•   1 tablespoon sugar

•   4 cups crushed ice

•   4 tablespoons salt

Tools:

•   2 quart size freezer bags

•   1 gallon size freezer bag

•   Hand towel or gloves

•   Tape (optional)

Procedure:

1.     Mix the milk, vanilla, and sugar together in one of the quart size bags.

2.     Seal tightly, removing as much air as possible. Too much air will force the bag open during shaking.

3.     Double bag the ingredient bag into the second quart bag. I like to put the top of the inner bag at the bottom of the second to minimize leaking.

4.     Put the double-bagged milk mix inside the gallon size bag.

5.     Fill the large bag with ice, then sprinkle salt on top.

6.     Again, let all the air escape and seal the ice bag.

7.     Wrap the bag in the towel or put your gloves on, and shake and massage the bag, making sure the ice surrounds the cream mixture.

8.     If you tape the towel tightly around the bag you can toss it like a ball if you are not TOO rough . . .

9.     Five to eight minutes is adequate time for the mixture to freeze into ice cream.

Lessons Learned:

When salt contacts ice, the freezing point of the ice is lowered.

Regular water will normally freeze at 32 degrees F. A 10% salt solution will freeze at 20 degrees F, and a 20% solution freezes at 2 degrees F.

By lowering the freezing temperature, an environment is created where the milk mix can freeze at a temperature below 32 degrees F.