How to Get Good Crema
- 1). Crema consists of the oils and sugars extracted from the coffee as it drips through the basket. Good crema is when everything goes right and you get the perfect combination of these soluble ingredients. The ultimate key to producing the best crema is practice. As a former barista, I wasted an entire can of inexpensive espresso to get this skill down before using quality ground espresso. Your portion of espresso in the basket must have the correct tamping pressure applied to it. This is approximately 25 pounds of pressure to get the correct "filter" for the water to pass through. If your pressure is too little, the shot will be under extracted and if it is too much it will be over extracted. The same issue comes from the grind being to large or too small. It is best to buy your espresso already ground until you get this part well practiced, or use the pre-compacted pods with a special pod basket for your machine.
- 2). Once you have all of the necessary supplies and practice, you will need to make sure that your machine heats your water to approximately 180 degrees. Dr. Ernesto Illy, of the famed coffee company, believed this to be the most important technical component of the espresso-making process. If you do not have the correct water temperature, the espresso cannot breakdown correctly for the crema to form or the shot to taste good. This is the optimal temperature to produce the best shot and the best crema. Measure your grounds into the basket, use your tamper to press the grounds into the basket. You must apply quite a bit of pressure (25 lbs.) with a little twist at the end to lock the coffee grounds together.
- 3). The best extraction times for most Italian espressos is 20 to 24 seconds. American grinds that tend to be less smooth in their roast flavor require only about 18 to 20 seconds. If this time is achieved and you have a rich, tiger-striped crema on the top of your espresso shot, you have done it. If it is really pale, either the grind was too large or the pressure of the tamp was too little (under extracted). If the crema is dark with oily bubbles, then the grind is too small or too much pressure was applied (over extracted). Make adjustments until you get the right look and taste with your particular machine or method. If it tastes and looks good, do not fret over slight imperfections.
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