Closed fermentation is the practice of fermenting beer in a closed container, where the CO2 produced during fermentation is allowed to escape, but outsider air is prevented from contacting the fermenting wort. Closed fermentation is the method most commonly used by homebrewers in the U.S. Some traditional British and Belgian breweries (and a few American micros as well) use open fermentation, where the fermenters are open to the air.
What is the Plato system?
Plato is the system of measuring the sugar content of a solution (beer wort), where the sugar content is expressed as a percentage by weight (10 °P wort contains 10% sugar by weight).
What does the Whirlpooling process do?
At the end of the boil, the wort is set into a whirlpool. This practice of spinning the wort in a circular motion causes the solids and spent hops to pile up in the center of the kettle - these are the solids the brewer wants to remove from the wort.
Originally published in our monthly newsletter, Micro Brew News, featuring Sierra Blanca Brewing Company located in Moriarty, New Mexico.