Batch pasteurizers are devices used to heat liquids, such as milk or juice, to a specific temperature for a set period. This process kills harmful bacteria and extends the product's shelf life while preserving its flavor and nutritional value. The batch method involves processing a large quantity of liquid at once, making it suitable for small to medium-scale production. These pasteurizers typically consist of a heating chamber where the liquid is heated, followed by a cooling phase. Pasteurization is named after Louis Pasteur, who developed the technique in the 19th century to improve food safety.