Calandria, a tubular heat exchanger that heats wort quickly and efficiently, enabling it to be boiled vigorously in the kettle.
Wort requires a long vigorous boil, normally of 60–120 minutes. Wort boiling releases bitterness from hops, reduces precursors for off-flavors such as dimethyl sulfide, coagulates proteins, and renders the wort sterile. It is an expensive process because the energy costs increase with each minute of boiling.
The calandria can be placed vertically inside a kettle or it can be external to the kettle and linked by piping and a pump. In an internal calandria, convection forces the wort up through the vertical bundle of tubes, where it is superheated by steam. When the calandria is external, the wort is pumped out of the kettle, through the calandria, and then back into the kettle again. Most kettle designs include a dish-shape wort spreader device that suppresses overfoaming, mixes the wort, and drives off unwanted volatiles. A calandria provides a larger area for heating the wort than does a direct fired kettle or those fitted with steam jackets.
The higher temperatures achieved using a calandria, typically up to 104.4°C (220°F) can reduce boil times up to 30% while also increasing hop utilization in brewing systems using hop pellets.