Espresso Brewing Ratios
Espresso brewing ratio is the ratio of ground coffee (dose) to the mass of the shot extracted (extraction yield). For example, a brewing ratio of 100% means that a dose of 20g has yielded a shot mass of 20g (1:1). Another example brewing ratio of 50%, means a 20g dose has resulted in a 40g shot mass (1:2).
Your barista should be able to tell you what espresso brewing ratio they are striving for.
Varying the brewing ratio can significantly change the taste and body of your coffee and is one of the explanations for the inconsistency encountered in the quality of coffee served up in many cafés. The best freshly roasted specialty coffee, perfect water and cleanest machine cannot produce perfect coffee if a poor brewing ratio has left you with an over or under extracted shot.
A rough guide to start finding the perfect espresso brewing ratio (best taste) for your favourite coffee is the following guide.
Ristretto 60 – 100%
Normale (regular espresso) 40 – 60%
Lungo 27 – 40%
Our personal brewing ratio preference for most specialty coffees is 60 – 70%. Beautiful full body and flavour range in a long black and fantastic with milk.
How to calculate espresso brewing ratios?
It’s simple and should be a part of every coffee lovers repertoire. In a café setting, a good barista will check their espresso brewing ratio regularly during the service, checking the dose, adjusting the grind and extraction time to ensure consistency.
- ensure the machine and portafilter are clean and pre-warmed. We use a 22g VST basket as we like a strong coffee. 18 – 20g baskets are common (double shot).
- weigh the empty portafilter and basket – alternatively weigh the basket. Use an accurate brewing/ dosing scale (they can be purchased quite cheaply).
- Grind your freshly roasted beans. Grind on demand – never leave grinds in the dosing chamber for more than a few minutes. Don’t leave beans sitting in the hopper for more than an hour.
- Dose the basket with the ground coffee, settle the grounds and groom the basket to ensure you have the correct dose (you should be able to consistently get within 0.5g every time). A Scottie Callaghan dosing tool is perfect. We aim for 22g with our 22g VST basket.
- Tamp (using about 15kg pressure) and polish using a quality tamper that is made for the basket you are using. All VST baskets are 58.4mm. Pullman or Reg Barber make beautifully crafted tampers.
- Measure your shot on the brewing/ dosing scale as it pours.
- TASTE – if it tastes fantastic be sure to record the brewing ratio and aim for that every time.
The pictures below show the process, it doesn’t add much time to your workflow and the consistency gained is well worth the effort.
In the example below we had a 22g dose to produce a shot mass of 35.6g extracted in 30 seconds (ideal extraction time is 25 – 35 seconds). The resulting espresso brewing ratio is approximately 62% – perfect for our taste in a long black, using our Symmetry blend.
Follow the links for information or purchase of VST baskets https://bostonbean.com.au/product-category/vst-baskets/
or coffee brewing scales: https://bostonbean.com.au/product-category/barista-tools/scales/