Extraction is used to describe how much or how little of the soluble flavour compounds you've managed to pull from the coffee. At home, the best way to tell how well extracted your espresso is, is to taste it.
Getting the right extraction from your espresso shot is a bit of trail and error to find the right balance of flavour.
If it's under-extracted, your coffee will taste sour and sharp and if it's over-extracted it will taste bitter and burnt.
The ideal time for extracting your shot is between 25-30 seconds for a balanced flavour. If your shot is pouring too fast, then your grind should be finer to prevent under extraction and get a more well rounded flavour profile. If it's pouring too slowly, your grind needs to be coarser to prevent over extraction and reduce the intensity of the flavour.
Is your espresso still not tasting right? There are other variables that can effect the flavour of your coffee- some of these you might have control others but others you many not.
Portafilter
Make sure your portafilter is clean and dry before beginning. Any residue from the previous extraction can off-balance your flavours. Wipe out the residue before adding in your new coffee dose.
Tamping
Apply even pressure when tamping your coffee, firm but not too hard so that your ground coffee is evenly distributed.
Temperature
Try adjusting your machine's temperature depending on what coffee you're using. Higher temperatures are good for light roasted coffee (around 94-97 degrees), while lower temperatures are well suited to darker roast profiles (around 92-94 degrees). Not matter the roast profile, your water should be between 92-98 degrees as this is the range in which the flavour compounds within coffee dissolve most easily.
If your coffee tastes flat, increase the temperature and if your coffee is tasting bitter, lower it.
Pressure
Make sure your machine has a consistent pressure, usually it should be at 9 bars of pressures but can drop a little and still produce good tasting coffee.
Water Quality
It's important to use soft, filtered water in your machine, this can affect the flavour of your coffee more than you think.
Looking to buy an espresso machine? Check out our Sage Espresso Machine collection - all machines come with a 5 month coffee subscription to get you started.
