Home Coffee Glossary: 15 Terms Explained
The words that show up in home coffee specs, reviews and how-to guides, explained without jargon.
- Bloom
- The first small pour in pour-over brewing that releases trapped carbon dioxide from fresh coffee before the main pour.
- Brew ratio
- The weight of coffee to the weight of water, written like 1:16. It is the single most useful number for consistent coffee.
- Related: Best Coffee Scales →
- Burr grinder
- A grinder that crushes beans between two burrs to an even particle size, unlike blade grinders that chop unevenly.
- Related: Best Burr Coffee Grinders →
- Channelling
- Water finding weak paths through the coffee puck, causing uneven extraction and a sour and bitter shot at once.
- Descaling
- Removing mineral build-up from a machine's water path. Frequency depends on your water hardness.
- Related: Best Descaling Solutions →
- Espresso shot
- A small concentrated coffee made by forcing hot water through finely ground coffee under pressure, commonly at a 1:2 ratio.
- Extraction
- How much flavour water dissolves from the grounds. Under-extracted coffee tastes sour, over-extracted tastes bitter.
- Gooseneck kettle
- A kettle with a thin curved spout for a slow, precise pour in pour-over brewing.
- Related: Best Electric Gooseneck Kettles →
- Grind size
- How fine or coarse ground coffee is. Espresso needs very fine, pour-over medium-fine and French press coarse.
- Microfoam
- Steamed milk with tiny, uniform bubbles and a glossy texture, needed for latte art.
- Related: Best Milk Frothing Pitchers →
- Portafilter
- The handled basket that holds ground coffee on an espresso machine.
- Related: Best Bottomless Portafilters →
- Roast date
- When beans were roasted. Most coffee tastes best within a few weeks of roasting, so it matters more than a best-by date.
- Single dosing
- Weighing and grinding only the beans for one brew instead of storing beans in the grinder hopper.
- Related: Best Single Dose Grinders →
- Tamping
- Compressing ground coffee in the portafilter into an even bed so water flows through it evenly.
- Related: Best Espresso Tampers →
- WDT
- Weiss Distribution Technique, stirring grounds with fine needles to break up clumps before tamping and reduce channelling.
- Related: Best WDT Tools →