Ristretto is traditionally a short shot of espresso coffee made with the normal amount of coffee but extracted with about half the amount of water. Since ristrettos are essentially the first half of a full length extraction, the faster-to-extract compounds predominate in a ristretto. The opposite of a ristretto is a lungo, which is typically double the shot volume. Ristretto means “limited” or “restricted” in Italian whereas lungo means “long.”
Regardless of whether one uses a hand pressed machine (top right) or an automatic, a regular double shot is generally considered to be around 14–18 grams of ground coffee extracted into 60 ml (2 fl oz or two shot glasses). Thus, a “double ristretto” consumes the same amount of coffee but fills only a single shot glass.
Coffee contains over a thousand aroma compounds alone. A ristretto’s chemical composition and taste differs from a full length extraction for three reasons:
- The first part of any extraction is the most concentrated, its color typically lying between dark chocolate and umber, whereas the tail end of shots are much lighter, varying from the color of dark pumpkin pie to varying shades of tan (see photo, below right).
- Different chemical compounds in coffee dissolve into hot water at different rates so a ristretto contains a greater relative proportion of faster extracting compounds and thus, a different balance.
- Relative proportions aside, overall, fewer total coffee compounds are extracted into ristrettos versus full length shots.
Straight ristrettos—shots that are traditionally drunk from a demitasse and not diluted into a larger cup containing milk or water—could be described as bolder, fuller, with more body and less bitterness. These characteristics are usually attributed to espresso in general but are more pronounced in a ristretto. Diluted into a cup of water (to make an Americano or long black) or milk (e.g. latte and cappuccino), ristrettos are less bitter and exhibit a more tamed “espresso” character.