Brewing and equipment
Mashing, lautering, boiling and your system. 34 terms.
All-in-one brewing system
- One unit for mashing, lautering and boiling, usually with heater, pump and grain basket.
Batch size
- The finished wort after the boil that goes into the fermenter. The batch size in the recipes means this amount.
BIAB (brew in a bag)
- The grain sits in a large grain bag in the pot. After mashing, the bag is simply lifted out. Often done without sparging, so all the water is mash water. Cheap and ideal for beginners.
Boil (wort boiling)
- The wort boils vigorously for 60–90 minutes without a lid. This sterilises it, the hops release bitterness, proteins clump together (hot break) and unwanted compounds such as DMS evaporate.
Boil-off (evaporation)
- Water that evaporates during the boil: usually 2–4 L (about 0.53–1.1 gal) per hour on all-in-one systems, 4–6 L (about 1.1–1.6 gal) in an open pot. Measure the volume once before and after the boil. Then you know your own value and hit the original gravity more reliably.
Brew log
- For every batch, write down the recipe, amounts, temperatures, times and all measurements such as original gravity, pH and final gravity. This helps you find mistakes, repeat good beers and get to know your system. Every recipe on this site is available as a printable brew sheet.
Cooling shrinkage
- Hot wort expands and shrinks by about 4 % as it cools, so it is best to measure the volume cold. The water volume calculator allows for the shrinkage automatically.
Coolship
- Shallow open vessel, usually under the brewery roof, in which the hot wort cools overnight. Once common in many breweries, today mainly used for lambic: wild yeasts and bacteria get into the wort and start spontaneous fermentation.
Dead space and kettle loss
- Water that stays below the malt pipe or false bottom is dead space. What is left in the kettle after the boil (hops, trub, the rest below the tap) is kettle loss. Both are missing in the fermenter at the end. Enter them in the water volume calculator under the fine settings.
Dry hopping
- Adding hops to the fermenter. Adds aroma but no bitterness.
Enzymes (alpha and beta amylase)
- They convert starch into sugar during the mash. Beta amylase works best at 62–65 °C (144–149 °F) and makes very fermentable sugar (a drier beer); alpha amylase works at 70–72 °C (158–162 °F) and makes less fermentable sugar (more body).
Ferulic acid rest
- Short rest at about 45 °C (113 °F) for wheat beer. It boosts the typical clove aroma of wheat yeast.
First wort hopping (FWH)
- Part of the hops goes into the wort during lautering, before the boil. This gives a smoother, rounder bitterness. The hops then boil for the whole time and count in the calculator like an addition at the start of the boil.
Grain absorption
- Malt soaks up water during the mash that never comes back out as wort, about 0.8–1.0 L (about 27.1–33.8 fl oz) per kg of malt. That is why you need more water than ends up as beer in the fermenter.
Homebrewing and beer tax
- In Switzerland, beer that you brew in your own household and drink yourself free of charge is tax-free up to 400 litres (about 106 gal) per calendar year; registered brewing clubs may brew 800 litres (about 211 gal). Anyone who brews more or sells beer must register with the Federal Office for Customs and Border Security (FOCBS). Other countries have their own rules; in the US, federal law allows 100 gallons per adult and year, up to 200 gallons per household.
Hop addition
- When the hops go into the boil. Recipes give how long they still boil: 60 min for bitterness, 10–15 min for flavour, 0 min or whirlpool for aroma.
Hop bag and grain bag
- Fine mesh bags made of nylon or cotton. A hop bag keeps the hops together during the boil; a grain bag holds the malt when mashing in a pot (brew in a bag, BIAB).
Infusion and decoction
- Two ways of mashing. With infusion, the whole mash is heated step by step to the rests, as is usual on all-in-one systems. With decoction, part of the mash is boiled separately and returned. It takes more work and gives more malt flavour.
Iodine test
- Test for remaining starch. If the sample no longer turns blue or purple, the starch is converted.
Isomerisation
- During the boil the alpha acids in hops turn into soluble, bitter compounds. That is why hops boiled for a long time give a lot of bitterness, while late hops mainly give aroma.
Lautering and spent grain
- Lautering separates the wort from the solid malt husks, the spent grain, which acts as a filter.
Lautering rest
- After mash-out the mash rests for 10–20 minutes. The grain settles and forms a filter bed through which the wort runs off clear.
Malt pipe (grain basket)
- The insert with a perforated bottom in all-in-one brewing systems. The grain sits inside and the pump circulates the wort through it. To lauter, the malt pipe is lifted, left to drain and rinsed with the sparge water.
Mash out
- Heating the mash to 78 °C (172 °F) and holding it briefly. Most enzymes stop and the mash becomes more fluid, so it lauters better.
Mash water and sparge water
- Mash water is used for mashing, sparge water is the 78 °C (172 °F) water used to rinse the grain bed.
Mashing in
- Stirring the crushed malt into the warm water. Enzymes then convert starch into sugar.
Milling (crushing)
- Cracking the malt coarsely in a grain mill, not grinding it to flour. The husks should stay as intact as possible because they act as a filter when lautering. Many shops sell the malt already crushed.
Pre-boil wort
- The wort in the kettle before the boil, after lautering and sparging. Part of it evaporates during the boil.
Rest
- Time at a set temperature during which specific enzymes work.
Saccharification (conversion)
- The part of the mash where starch turns into sugar, usually at 62–72 °C (144–162 °F). The iodine test shows when it is complete.
Trub (hot and cold break)
- Protein and hop residue that clumps together during the boil (hot break) and when cooling (cold break). Leave as much as possible in the kettle, for example with a whirlpool.
Whirlpool
- Swirling the wort after the boil so trub collects in a cone in the middle. Whirlpool hops add lots of aroma and little bitterness.
Wort
- The sugary liquid from mashing and lautering. Only after the yeast is added and ferments the sugar does it become beer.
Wort chiller
- Copper or stainless steel coil with cold water running through it. It cools the wort to pitching temperature in 20–30 minutes. Fast cooling protects against infection and gives a clearer beer.