A batch freezer is a piece of equipment used in the commercial production of ice cream and frozen desserts, like gelato and sorbet. As the name suggests, this freezer makes frozen desserts in batches that can vary in size, with the size of each being controllable by the operator. Many small ice cream stores and gourmet shops make their ice cream in this way; large-scale commercial concerns use what is known as a continuous freezer, capable of producing huge volumes of ice cream.
This type of equipment stands somewhere between a home ice cream maker, which typically makes a very small volume of ice cream at a time, and a commercial continuous freezer, used on the production lines of large companies. A typical batch freezer might make up to 24 quarts (22 liters) of ice cream, while a continuous freezer's capacity is potentially endless.
A typical batch freezer looks a little bit like a washing machine, and it works rather like one, too. It has a large central chamber, which may be tilted on its side, along with a locking door to secure the chamber. Inside, a very large rotating blade is used to mix and stir the ice cream as it is frozen from the outside in, using cooling coils built into the casing. After a set period of time in the freezer, a small gate is opened to allow the ice cream to flow out into containers, which must typically be put into a blast freezer to harden.
Typically, frozen desserts fresh out of the freezer are not fully frozen. Instead, they are very thick, soft, and creamy, with a very distinctive flavor and texture that cannot be replicated. After blast freezing, the dessert will have hardened to a point where it is recognizable to consumers as ice cream or sorbet, and it can be served from display cases in a shop or packaged in smaller containers for individual sale. If the larger style of packing is planned, the dessert may be pulled directly into these containers from the batch freezer, because this is far easier than repacking.
All sorts of frozen desserts can be made with this device. Many commercial concerns use a basic dairy mix for ice cream as a base, adding flavorings and other inclusions. It is also possible to start from scratch, making a basic fruit ice or a rich custard ice cream with an egg base. Many freezer owners enjoy experimenting with a variety of ingredients and flavorings, since this equipment is easy to use.