A fancy word that baristas use instead of ‘stirring’. Try our bamboo stirrer!


The start of the coffee brewing process where gas is escaping the coffee grounds as they become saturated with water.

Brew Ratio

The ratio of ground coffee to brewed coffee liquid. Often expressed as grams per litre.

Coffee Bed

The level bed of coffee at the bottom of the filter brewer (or in the espresso basket) which water is added to.


Normally used in reference to espresso, refers to the action of levelling coffee grounds in the filter basket.

Espresso Roast

In comparison to a filter roast, an espresso roast features more caramelisation and roast development leading to better body and more balance in the cup.


Also called ‘solubility yield’, extraction refers to the amount of soluble compounds extracted from the coffee bean. Normally expressed as a percentage, extraction is related to and varies with strength.

Filter Roast

In comparison to an espresso roast, a filter roast features less roast development and hence more vibrancy and acidity in the final filter cup.


The extra-fine particles produced by a coffee grinder as part of normal grinding.

Filter Paper

A paper filter used in filter brewing devices (pourover, aeropress, chemex etc)

Fresh Roasted

We deem coffee as ‘fresh roasted’ if it has been roasted within three weeks of use.

Particle Size

The size (diameter) of the coffee particles produced by a coffee grinder. Changing particle size alters the flow rate of water through the coffee bed.


Coffee strength is a tricky topic. When we talk about coffee strength, we refer to the dissolved solids (TDS) in a given coffee brew.


Saturation refers to the way coffee grinds are wet by the brew water in a filter brewer or espresso basket. Even saturation leads to even extraction, the main goal in coffee brewing.


The volume of water produced by a filter brew, or the weight of the espresso shot.

Date Published

Friday 5th August 2015

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