Science Bob: Ice Cream With Plastic Bag

(NECN) - Ice cream is always a sweet treat, but it's even sweeter when you get the option to make it at home.

Science Bob returned for some more summer fun - and taught Steve and Bridget how to make ice cream using the help of a plastic bag!

Watch the attached video to catch the action, and try it for yourself at home:

4 oz of milk 

4 oz of cream 

1/4 tsp of vanilla 

4 tsp of sugar 

Lots of ice 

Lots (half cup) of salt

 -- Rock salt (sold at hardware stores) works best.

Small (quart size) zip-lock freezer bag Large (gallon size zip-lock freezer bag) 

· Put the milk, cream, vanilla, and sugar into a bowl and mix them together well. Pour the mixture into the SMALL zip-bag and zip it shut (be sure it is zipped up well) 

· Put about a cup of ice into the large bag and the cover the ice with a small handful of salt. Put the small bag with your ingredients into the larger bag. 

· Add some more ice and then some more salt. Keep adding salt and ice until the bag is almost full. 

· Zip it shut (be sure it is zipped) and then carefully shake the bag back and forth (like your steering a car) for about 5-8 minutes. 

Open the larger bag and take out the smaller bag - it should be full of ice cream! Rinse off the bag under running water to remove any salt that may be near the opening of the bag. Open and enjoy! 

The Science of Ice Cream - When you added salt to the ice, it forced the ice to melt. Before the ice could melt though, it needed to borrow heat from objects that surround it. 

Since your ingredients are not as cold as the ice, it borrowed heat from your ingredients making them colder! 

When they get colder, they freeze up into ice cream. Yum!