Miss Biergard has been teaching the tamariki about procedural texts. The tamariki have been learning how to recognise and write a procedural. As part of the this learning, they have been getting stuck into some cool science experiments. Today, we made ice cream. Have a look at the photos below:

PLASTIC BAG ICE CREAM

Yes, it sounds dangerous and the potential for messes seems highly likely, but you’ll be surprised at the good, “clean” fun you’ll enjoy when you make ice cream. The key to success is to plan smart and follow the simple instructions. 

This recipe is enough for one person, so that each student can make their own.

Requirements

1/2 cup milk
1/2 teaspoon vanilla
1 tablespoon sugar
4 cups crushed ice
4 tablespoons salt
2 smalll Zip-loc bags
1 large Zip-loc freezer bag
a hand towel or gloves to keep fingers from freezing as well!

Method

First, mix the milk, vanilla and sugar together in one of the small Zip-loc size bags. Seal tightly, allowing as little air to remain in the bag as possible. Too much air left inside may force the bag open during shaking. 

Next, place this bag inside the other Zip-loc  bag, again leaving as little air inside as possible and sealing well. By double-bagging, the risk of salt and ice leaking into the ice cream is minimised. 

Put the two bags inside the largesize bag and fill the bag with ice, then sprinkle salt on top. Again let all the air escape and seal the bag. 

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

Tips
Freezer bags work best because they are thicker and less likely to develop small holes, allowing the bags to leak. You can get away with using regular Zip-loc bags for the smaller sizes, because you are double-bagging. Especially if you plan to do this indoors, we strongly recommend using gallon size freezer bags.

What does the salt do?
Just like we use salt on icy roads in the winter, salt mixed with ice in this case also causes the ice to melt. When salt comes into contact with ice, the freezing point of the ice is lowered.

Who invented ice cream?
Legend has it that the Roman emperor, Nero, discovered ice cream. Runners brought snow from the mountains to make the first ice cream. In 1846, Nancy Johnson invented the hand-cranked ice cream churn and ice cream surged in popularity. Then, in 1904, ice cream cones were invented at the St. Louis World Exposition. An ice cream vendor ran out of dishes and improvised by rolling up some waffles to make cones.