Change Your Coffee Grind Size Coarsen (increase) the grind size if your shot pulls too slowly or it tastes over extracted. Fine (decrease) the grind size if your shot pulls too fast or tastes under extracted. Again, these grind size adjustments need to be very small.
Grinding finer increases extraction. As you grind finer it will easier to extract but also you will increase the brew time at the same time which will also increase extraction. The more water and coffee spend time together, the more coffee will give for itself to the water.
However, while some myths come and go, one that's stuck is the concept of the ten-second espresso. Essentially, this school of thought maintains that a shot of espresso should be consumed – or mixed with milk or other ingredients like milk – within ten seconds of brewing. If not, it spoils.
The effect of temperature on extraction and flavour
There are many variables involved in espresso extraction, including grind size, dose, tamping, extraction yield, brew ratio, time (as a consequence) and water temperature, to name just a few.
Fix Your Coffee to Water Ratio
Maybe you are using too little coffee or not enough water. Extraction is all about water and coffee contact, so the amounts of both are essential to a good extraction. The golden ratio for coffee brewing is 1 gram of coffee to 15 grams of water.
quality indicators for espresso coffee extraction: changes in colour of crema. changes in flow texture. cake of used ground coffee.
If you over or under extract your grinds, milk is the perfect cover up. But espresso is less forgiving. That's why you should always aim to let your espresso extract for 25 – 30 seconds.
As espresso sits, some important chemical reactions take place. All of the lovely oils and lipids that give coffee their rich body and long aftertaste will oxidize. This results in funky, off flavors of rancid fats (think musty or acrid).
In regular espresso machines, using the wrong coffee grind size is the most common reason for no crema. Espresso requires a much finer grind size than drip coffee or normal ground coffee for general coffee machines. Espresso grounds should ideally be finer than table salt.
The Operating Pump Pressure Is Wrong
Since coffee grounds must be tightly compressed, your machine needs to force water through them with a high degree of pressure. If your operating pump pressure is set too low, your coffee will dispense too slowly—or sometimes it won't dispense at all.
Getting too much extraction from the coffee grounds can make the espresso taste bitter. So, during the espresso tamp, the goal is to apply a sufficient amount of pressure with the tamper, but not excessive pressure.
The ideal brewing time you're looking for is between 20 – 30 seconds – if you're running too long or too short, check your grind, dose and tamp, then adjust it accordingly.
Espresso extraction should produce a double espresso of 50-60ml in 25-30 seconds or a single espresso of 25-30ml in the same time. Before you connect the filterholder (loaded with coffee) to your espresso machine it is a good idea to to flush some water from the machine.
When you make coffee more coarse - more water will also pass through the coffee quickly. If your espresso or brew is too long, a coarser grind is what you are looking for. Fine - Think of a finer grind as you would think of a jar of sand. The smaller the sand particles, the slower water will pass through the jar.
Therefore, we will pull 36g of liquid espresso in 25-35 seconds. For example, we should aim to extract 36g of liquid espresso from the 18g of ground coffee in 30 seconds, giving us our target ratio of 1:2.
There are three qualities to pay attention to when you taste your espresso — acidity, sweetness and bitterness. The acidity is often described as the citrusy, tangy taste of your coffee. It's sometimes compared to actual citrus fruit like lemon, orange and lime, as well as berries, apple and melon.
The most common brew ratios that you'll see are a ristretto, traditional and lungo shot. The ristretto shot is also known as a restricted shot, and typically features a brew ratio between 1:1 and 1:1.5. A traditional espresso is typically 1:2-1:2.5 and a lungo, or long shot, is usually about 1:3.
Bitterness, for example, is one of the key signs that a brew could be overextracted—yet coffee is inherently bitter and a little bitterness is indeed desirable. It's when a brew is excessively bitter that it's likely overextracted.
If you've got these initial steps down, your espresso should take somewhere between 20 and 25 seconds to brew. The stream of espresso coming out of the portafilter should look something like thick, warm honey. The finished shot should be golden and have a crema thickness of about 1/4" to 1/3".
The first and foremost reason why your espresso might be pulling fast could be that you're not grinding at a fine enough consistency. The rule of thumb with espresso grind size is that the coarser the grind is, the faster it will pull the espresso.