Liquid Nitrogen Ice Cream

For our final project, we decided to make ice cream with liquid nitrogen. During this experiment we demonstrated how to rapid freeze with liquid nitrogen. We made a vanilla ice cream mixture using 1 quart of half and half, 1 pint of milk, 3/4 cup of sugar, and 5 1/2 tablespoons of vanilla, then mixed it together until all sugar was dissolved. We then added liquid nitrogen. Liquid Nitrogen is a very cooled down version of the nitrogen in the atmosphere, being -320 degrees (F). Liquid nitrogen is beyond frostbite and is particularly used to freeze food because it’s odorless, colorless, and tasteless. Liquid nitrogen is not considered an ingredient when you are cooking, because it is a technique. This technique that we used is called molecular gastronomy which is the scientific discipline involving the study of physics and chemical process that occur during cooking. So, the first few trials we were unable to come out with a creamery texture, the mixture came out as a liquid. Then we finally figured out that since we were using low fat milk there was not enough fat to create the creamery texture and to avoid the ice crystals. So, we used whole milk, which has more fat in it.
During this reaction the liquid nitrogen causes the fat and the water molecules to stay very small, giving the ice cream a creamy look and taste. After you poor the liquid nitrogen let it sit for about a few minutes until the fog stops appearing and the sizzling sound stops. The liquid nitrogen will mix with the milky mixture and creates super small ice crystals that make the ice cream very smooth and creamy texture.

 As we poured in the liquid nitrogen we saw a fog that was cold when we touched it. You guys will also hear a sizzling sound, while the reaction occurs, but it is defined as crystalizing, which is the process of changing a liquid to a solid. When you see the fog burning off of the mixture it is the nitrogen burning off and water vapor that makes the nitrogen visible. The liquid Nitrogen changed the liquid mixture into a solid. Once we blended that together it became creamy but was still very liquid like, so we added liquid nitrogen and repeated the process. The mixture then became a very creamy texture and had a creamy ice cream taste.
By: Molly O'Brien and Ariana Feliz