ESPRESSO #2 - Ratio
Because not every coffee has the same water solubility, whether due to degree of roast or origin of the bean, the coffee to water ratio must be continually adjusted to bring out the best in each.
Since an espresso is subjected to around 9 bar of pressure, a small change can have a big impact. Here we will try to reduce the amount of trial/error in your process.
You will need a scale and a stopwatch for the purposes of the cause.
Since we need to have a starting point, as in every experimentation process, the ratio that is often used for espresso is 1:2 (1 part coffee to 2 parts water)
So if 18g of coffee is ground in my portafilter (which your machine's dual filter should hold), I will extract 36g of espresso into my cup.
Indeed, it is not very rocket science as a formula, but what comes to confuse the cards? The weather...
1:2 is all well and good, but how long does 18g of coffee have to take to turn into 36g of espresso?
Aim for an extraction between 25 and 35 seconds to start. Some coffees are going to be enhanced with a faster extraction and others with a slower extraction.
What comes into play next is the grind.
To lengthen the extraction = finer grind (the water will take longer to cross the coffee)
To shorten the extraction = coarser grind
Let's forget the numbers and calculations for a moment...
Before throwing away an espresso because according to your data it is not successful, TASTE IT! Either way, it's possible that your last extraction settings were the best for that coffee, or more importantly, for your tastes.
Then, the changes you make to all the variables of these extractions will be linked to your preferences. In any case, trust your taste buds and not the scientific graph of your extraction.
TO GO A LITTLE FURTHER...
To guide you on how to modify the variables, here are a few tips:
- The espresso is too acidic, even sour: lengthen the extraction time by reducing the grind.
- The espresso is bitter, lacks clarity and acidity: increase the ratio.
- Once diluted in milk, the espresso loses its presence: reduce the ratio and lengthen the extraction time.
These are just some examples of what can be performed to alter the end result in the cup. Do not hesitate to write to us with your questions.
Finally, don't be afraid to change the extraction parameters from one coffee to another to be able to find the combination that will be ideal. It is not because the new bag you have just bought does not satisfy you at the first espresso that it will not surpass those of before after a few small adjustments...