slushie

Production

Carbonated slushies are made in machines similar to regular soda fountains. Concentrated flavor syrups are mixed with filtered water, then carbonated. This mixture is then injected into a cylinder surrounded by freezer coils. The mixture freezes to the wall of the cylinder, then is scraped off by a rotating dasher, which also keeps the mixture uniformly mixed. Carbonated slushie machines often freeze to a temperature well below the freezing point of water, but the combination of pressure up to 40 psi (2.8 bar), the carbon dioxide mixture that freezes at −80 °C (−112 °F), the sugar, and the constant stirring prevent the mass from freezing solid. Carbonated slushies tend to be "drier" than their non-carbonated counterparts.