With the introduction of mechanical freezing in the 20th century, the production of ice no longer depended on nature. A major industry using mechanical refrigeration evolved and focused on the production of ice in different shapes and by a number of different methods.
Slurry ice is a water-based solution mixed with ice crystals. Slurry ice can be produced by mixing water with a freezing point suppressant and then cooling this mixture so the ice crystals can be formed. The subsequent temperature of the slurry ice solution depends on the percentage and type of additives used to suppress the freeze point. Common suppressants include sugars, salts, glycols, and alcohols.