What better way to cool off on a hot summer afternoon than to relish deliciously cold ice-cream!
An ice-cream maker consists of a metal pot in which ingredients like milk, sugar, eggs, and flavoring agent are added. This pot is kept inside another metal container to which salt and ice are added. The salt lowers the freezing point of ice thus allowing a thin layer of milk to freeze on the inside of the inner container. Ice cream is made by scraping the frozen layer from the edge, allowing a new layer to freeze, and repeating the process until the whole mixture is frozen.
During the early part of the nineteenth century, the ice cream mix in the inner container was agitated by hand. This process though effective was very labor intensive. Hence ice cream could be enjoyed only by the upper class.
Credit for making ice-cream maker popular among the masses goes to a humble housewife from Philadelphia who received the first U.S. patent for a hand-cranked ice-cream freezer in 1843. Johnson’s ice-cream maker had the same basic design. However it had a crank on the outside which was connected to a rotating paddle, also known as dasher’, on the inside. The dasher would scrape the frozen ice-cream from the edge of the container repeatedly. When the mechanism stopped turning, the ice cream was frozen and ready to eat.
Johnson’s ice cream had a smoother consistency, thanks to the consistently cold environment and constant stirring made possible by her machine. Johnson sold the rights of her invention to William G. Young, who marketed the product as ‘Johnson’s Patent Ice-Cream freezer’. Many home ice cream makers currently on the market run on electricity but have the same basic design as that of Johnson.