Tuesday, September 13, 2011

Liquid Nitrogen Icecream

This is one of my favorite experiments to learn about safe handling of liquid nitrogen.  There are many recipes on the web, here is one that looks tasty!

Liquid Nitrogen Ice Cream

5 or more liters of liquid nitrogen and associated safety gear
2 quarts (1.9 liters) of Half and Half1 cup (237 ml) of sugar
4 teaspoons (20 ml) of vanilla (optional)
2 cups (473 ml) of strawberries (or whatever flavor you like)
wooden spoon
wire wisk
large plastic punch bowl

1. Mix the Half and Half, sugar and vanilla in a large plastic punch bowl with a wire wisk.2. Add the flavoring. Wire wisk the mixture further if needed.
3. Pour a small amount (about 250 ml) of liquid nitrogen directly into the plastic punch bowl.
4. Stir the mixture with a wooden spoon. Be careful not to splash!
(Anyone near should be wearing gloves and goggles!)
5. Keep adding small amounts of liquid nitrogen until the mixture becomes too thick to stir. 6. Allow any excess liquid nitrogen to boil off before serving.

"Liquid nitrogen is nitrogen in a liquid state at a very low temperature. It is produced industrially by fractional distillation of liquid air. Liquid nitrogen is a colorless clear liquid with density of 0.807 g/mL at its boiling point.  At atmospheric pressure, liquid nitrogen boils at 77K (-196C; -321°F) and is a cryogenic fluid which can cause rapid freezing on contact with living tissue, which may lead to frostbite.”

What would happen if you dip a balloon filled with air into liquid nitrogen?  Try it!  Why did God create nitrogen? What is the chemical symbol for nitrogen?  What is your favorite ice cream? Would liquid nitrogen change the flavor of ice cream?  What would you do with an endless cheap supply of liquid nitrogen?  How much does liquid nitrogen cost?  How long will it last in your refrigerator? How would this be helpful on a farm?

References 1, 2