The mechanical separation of the sugar-rich liquid extract from the solid husks and grain bed. The process involves recirculating the liquid until it runs clear, draining the primary extract, and then sparging the grain bed with hot water to rinse out the remaining sugars. A well-formed grain bed acts as its own filter medium, trapping proteins and particulate matter to yield a clear liquid for the boil.
Keep an eye on the differential pressure while lautering so we don't stick the mash and collapse the bed.
Rushing the runoff speed will compress the grain bed, leading to a stuck sparge and a massive headache on the brew deck.
Do not mix it up with
- Mash: Mashing is the enzymatic conversion of starches to sugars, while lautering is the physical separation of that sugary liquid from the grain.
Related terms
Mash
A hot mixture of crushed malt and water where enzymes convert grain starches into fermentable sugars.
Mash tun
An insulated or heated vessel where crushed grains and hot water are mixed to convert starches to sugars.
Wort
The sweet, unfermented liquid extracted from mashed grains that serves as the basis for beer or whisky.
Underback
A collection vessel located below the mash tun that receives the sweet wort as it drains.