Ice cream churns the ice cream mixture while cooled inside a household freezer. Some more expensive models have an inbuilt freezing element. A newer method is to add liquid nitrogen to the mixture while stirring it using a spoon or spatula for a few seconds; a similar technique, advocated by Heston Blumenthal as ideal for home cooks, is to add dry ice to the mixture while stirring for a few minutes. Some ice cream recipes call for making a custard, folding in whipped cream, and immediately freezing the mixture. Another method is to use a pre-frozen solution of salt and water, which
Ice cream from traveling refrigerated vans or carts (commonly referred to in the US as "ice cream trucks"), sometimes equipped with speakers playing children's music or folk melodies (such as "Turkey in the Straw"). The driver of an ice cream van drives throughout neighborhoods and stops every so often, usually every block. The seller on the ice cream van sells the ice cream through a large window; this window is also where the customer asks for ice cream and pays. Ice cream vans in the United Kingdom make a music box noise rather than actual music. In the U.S., ice cream must