A Glossary of Winemaking Terms

If you’re just starting out in winemaking, all the new terminology can make you dizzy well before your first sip. Never fear. A biology degree on your curriculum vitae is not a prerequisite for becoming a home vintner. But learning a few key terms will help make the process less mysterious and more fun even faster. This glossary will be gradually filled in as we go through the steps of winemaking.

Brix - the sugar content of wine. One-degree Brix is 1 gram of sucrose in 100 grams of solution and represents the strength of the solution as percentage by mass. If the solution contains dissolved solids other than pure sucrose, then the °Bx only approximates the dissolved solid content. In other words, Brix is a rough measurement of sugar, but it will suffice for our purposes. 

Cap Formation – during active fermentations the skins rise to the top and become crusty. This cap is what is pushed back into the must during punch down. 

Crush – the act of crushing whole grapes into a fermentation tub and removing the stems. 

Fermentation – primary fermentation is where the yeast converts sugar to alcohol. 

Free Run – the juice that can be suctioned from the fermentation tub before pressing the skins. 

Lees – after the wine is fermented and in the barrel, solids or sediment called the lees begins to fall to the bottom of the barrel. 

Malolactic Fermentation – is a secondary fermentation that changes malic acid to a softer lactic acid. This is done for a better mouthfeel of wine. 

Must – the combination of skins, juice, seeds, and a few stems that fall from the crusher into the fermentation tub. 

Pitch – the act of adding the yeast and yeast nutrients to the must.

Press – the act of pressing the grape skins to get all juice out of the skins when fermentation ends.

Punch Down – performed during fermentation to push the skins under the juice. This helps extract the color and tannins from the skins and also helps control the fermentation temperature.  

Racking – racking is very carefully moving wine off of the barrel into another container, rinsing the barrel, and then adding the wine back into the barrel.  This gets the wine off of the lees which helps make the wine more palatable and clarified. 

Photo by AndressaRodrigues--40306