A less common culinary use for liquid nitrogen is in grinding ingredients, particularly high-fat products, to create powders or purees. For example, fresh raw peanuts may be frozen in liquid nitrogen and put through a juicer to create a completely uncooked peanut butter that preserves all the flavor of the raw nut. Olives may be partially dehydrated, frozen, and ground into a fine seasoning powder that would not normally be achievable due to their high fat content. Cooked shrimp and other proteins may also be frozen and ground and used for various preparations.
Fruits and vegetables may be frozen instead of cooked to tenderize them. The freezing process creates ice crystals, which poke microscopic holes into the cell walls. When the ingredients are defrosted, they are slightly tenderized but still retain some of their original texture and their raw flavor. While in their frozen state the fruits and vegetables can be shattered, and the pieces then used for a dramatic presentation in a finished dish.
Finally, liquid nitrogen is perfect for chilling down hot preparations quickly and efficiently. This minimizes the development of bacteria and harmful microorganisms in the food. A batch of spaghetti sauce or a pot of chicken curry can go from boiling to ice cold in five minutes' time. In terms of food safety, this is a very good thing.
What this all boils down to is that liquid nitrogen is a very useful tool to have in the kitchen. Playing with ice can be just as satisfying as playing with fire, under the right circumstances. To get you started, we've included a recipe for shattered raspberries with coconut-yuzu ice cream. You can make this ice cream traditionally and garnish it with fresh raspberries -- or you can find some liquid nitrogen and see what kind of magic it can do.
Dewars can often be bought on eBay or rented from companies who supply liquid nitrogen. If you live in the New York City/Long Island area, General Welding Supply Corp., 600 Shames Drive, Westbury, NY 11590, (516) 334-8200, is a reliable source for liquid nitrogen.single page
Five amazing, clean technologies that will set us free, in this month's energy-focused issue. Also: how to build a better bomb detector, the robotic toys that are raising your children, a human catapult, the world's smallest arcade, and much more.