Over-extracted and under-extracted with the imperfections of Espresso Shot

Espresso is known as the base for other types of coffee. Whether Cappuccino, Americano or Latte are all essentially the shots of espresso before being mixed with various ingredients to get the desired flavor. Fresh coffee is a drink that coffee lovers need to be meticulous. An avid drinker, of course, you want a perfect espresso, but sometimes baristas miss a great cup of coffee.

The major observation after newly extracted coffee, it generally has a creamy foam on top termed "crema" at half layer of shot. Then, it will collapse but intense flavor is still the same. The Crema is a signal that is visible from the sight that the coffee shot is perfect.

If the crema is golden brown or like brown sugar, it’s considered a good coffee. But if distortion occurs, it may have to reprocess the steps to find cause of such problems that can start from choosing extracted coffee beans come out with unwanted thing. As a result, Espresso creates something called over-extracted or too much of the soluble flavors out of the coffee, and another is under-extracted or too small extracted out of the coffee.

The nature of the over-extracted coffee shot

Over-extracted coffee as mentioned above means uncompleted extracted coffee shot. It’s too much extraction noticed that the crema color is very dark and black spot on top of surface area. Even though it looks like a dark color, but the coffee taste is lack of flavor and having burnt smell.

The taste skips to the bitterness made unpalatable coffee. The reasons are caused by too high temperature water caused the roasted coffee being burned more. Resolved by adjusting suited water heating. Especially, the too long time of extraction has also caused over-extracted problems.  Therefore, any "too much" environmental factors will give us a bitter and burnt espresso shot rather than a soft aroma.

The nature of the coffee shock Under-extracted

Under-extracted coffee is the opposite of the first coffee which means the coffee has been extracted too quick. We can clearly notice that the color of crema is soft, faded, quickly collapse and not intense. If you try it, you will feel the sourness that is not delicious. Its sourness should not be contained in the coffee flavor. The cause is due to water temperature as well. Meaning that, the too low temperature is unable to fully extract the flavor of the coffee, including spending too little time. It can be said that the problem of espresso coffee shot is usually comes from the environmental factors as opposed to over-extracted coffee.

In addition, the distorted taste is made espresso shot unpalatable which may be from the quantity of coffee that is put in more or less in the process of compression into the coffee machine or pressure process. Grinding coffee beans is related to the fineness of the shot taste. To create good flavors, you should observation leaning by tasting coffee shot each glass to adjust the coffee taste that is the starting point for various types of coffee as perfect as possible.

Reference :  https://www.coffeefavour.com/under-and-over-extracted-espresso-shot/