Home Brewing Glossary – The Homebrew HQ

Immersion Chiller

A wort chiller with a coil of copper or stainless steel tubing that is immersed in the wort while cool water flows through.

Plate Chiller

A wort chiller similar in function to a Counter Flow Chiller, but made up of a series of stacked plates instead of tubing.

Counter Flow Chiller

A wort chiller with two coils, one inside the other. The wort is pumped through the inner coil while cool water is pumped the opposite direction through the outer coil.

Wort Chiller

A device for cooling wort down quickly after the boil has finished. There are three major types of wort chillers.

Immersion Chiller: A coil of copper or stainless steel tubing that is immersed in the wort while cool water flows through.
Counter Flow Chiller: Two coils, one inside the other. The wort is pumped through the inner coil while cool water is pumped the opposite direction through the outer coil.
Plate Chiller: Similar in function to a Counter Flow Chiller, but made up of a series of stacked plates instead of tubing.

Wort

Is the liquid produced during the Mash. Wort is a solution of sugars, proteins, hop oils, alpha acids, and other flavor compounds. It is boiled to sterilize, coagulate proteins, and isomerize alpha acids. Wort is what yeast ferment into beer.

Final Gravity (FG)

A measurement of Specific Gravity taken at the end of fermentation. This measurement is compared to the Original Gravity to give the alcohol content of the finished beer.

Original Gravity (OG)

A measurement of Specific Gravity taken right before yeast is pitched into a beer. This measurement is compared to the Final Gravity to give the alcohol content of the finished beer.

Pre-Boil Gravity

A measurement of Specific Gravity taken after the mash, but before the boil begins. This measurement indicates the efficiency of the mash.

Specific Gravity (SG)

A measurement of the density of wort or beer. This indicates the amount of sugar and/or alcohol in solution. The higher the SG the higher the amount of dissolved sugars. By comparing the SG at different times during the brewing and fermenting processes, we can determine the efficiency of the brewhouse and the alcohol content of the beer.

Pre-Boil Gravity: A measurement of Specific Gravity taken after the mash, but before the boil begins. This measurement indicates the efficiency of the mash.
Original Gravity (OG): A measurement of Specific Gravity taken right before yeast is pitched into a beer. This measurement is compared to the Final Gravity to give the alcohol content of the finished beer.
Final Gravity (FG): A measurement of Specific Gravity taken at the end of fermentation. This measurement is compared to the Original Gravity to give the alcohol content of the finished beer.

Refractometer

A device for measuring the amount of sugar and/or alcohol in solution in wort or beer (specific gravity). A few drops of wort or beer are placed on the prism and refract light different amounts depending on the density of the liquid.

Mash:

Verb: The process by which grist (crushed malted barley or other grains) is steeped in hot liquor (water), to activate malt enzymes (alpha and beta amylase), which convert starches into fermentable sugars (maltose) and unfermentable sugars (dextrins). Noun: The grist and liquor mixture.

Liqour

What Brewers call water used for brewing.

Kettle

Large pot for heating or boiling water or wort. Typically made of stainless steel or aluminum.

Hydrometer

A device for measuring the amount of sugar and/or alcohol in solution in wort or beer (specific gravity). Similar in appearance to a glass thermometer, hydrometers are floated in the wort or beer and float higher or lower depending on the density of the liquid. The higher it floats, the higher the specific gravity.

Grist Mill

A device for crushing grains in order to expose the kernels. This allows the malt enzymes to convert the starches during the mash.

Grist

Crushed grains, typically malted barley, but often including adjunct grains such as corn, wheat, oats, or rye.

Fermentation

The process by which yeast consume fermentable sugars (typically maltose) and excrete alcohol and co2 gas. This is when beer is actually made. Brewers make wort, Yeast make beer.

Boil Time

The boil runs on a schedule, typically 60 to 90 mins long. Most recipes list additions added at a specific boil time in minutes left in the boil. Example: 0.50 oz – Mosaic – Boil 15 mins. This indicates that ½ oz of Mosaic hops are to be added to the boil when there are 15 mins left in the boil time.

Airlock

A device that allows co2 gas to escape the fermentor, while keeping air and other contaminates out.

Adjunct Grain

Grain other than barley used in the mash. These include; corn, rice, oats, wheat, rye, sorghum, and other cereal grains.

Boil

The process by which wort is heated to boiling to sterilize, coagulate or denature proteins from the mash, and isomerize alpha acids. The boil is usually said to have begun when you see the hot break beginning to form. Hops and other additions are typically added during the boil.

Fermentor

A sealable container in which yeast ferments wort into beer. Typically homebrewers use such fermentors as; food grade plastic pails, glass or plastic carboys, or stainless steel conical fermentors.