Nine Things That Your Parent Teach You About Machine Espresso > 자유게시판

• 목록
• 답변
• 글쓰기
• 게시판 리스트 옵션
  • 수정
  • 삭제

How Does Machine Espresso Work?

Machine espresso uses precision pressure and incredible filter technology to produce the perfect cup of coffee. What exactly does it work?

In order to make espresso hot water is forced under high pressure through finely ground coffee. The process is similar to making drip coffee. However the pressure is the main difference.

The Group Head

The name implies the group head is where you place your portafilter when brewing professional espresso maker. It is responsible for dispersing the water into the portafilter before controlling the pressure that results from the extraction. There are many different types of group heads, each with its own advantages and disadvantages. Some are designed to provide temperature stability while others are designed to handle pre-infusion. Some are designed to control the lever. There are also some that include a mix of features, like the E61 that is the classic choice among many baristas due to its capacity to provide multiple benefits in a single package.

As you can see from the image above the head of the group is equipped with several notches. You can place your portafilter in these notches and then turn the head around to secure it. A gasket of rubber is situated in the notches to create a seal while you insert your portafilter. The notches allow for precise placement of your portafilter. This is crucial for an efficient extraction.

The group head does not just allow you to insert your portafilter easily however it also keeps an even temperature. This is achieved by cycling hot water around the portafilter and through the brew-basket to ensure that the temperature is constant to extract the coffee. It is important to note that even a slight difference can make the difference between a good and a great espresso.

The Pump

In contrast to manual piston machines that use a lever to pressurize water, the rotary espresso machines use motorized pumps to provide the nine atmospheric bars of pressure needed to extract espresso. The pressure builds up by removing tap water from a reservoir, and pumping it through a heat exchanger prior to being pumped through the ground coffee in the group head.

Pumps are typically cheaper and last longer than piston-driven machines. However, both kinds of machines can deteriorate because of frequent use and poor cleaning. Pumps are also more complicated mechanically, which can raise the price of even the simplest models.

Certain espresso machines do away with the pump completely and instead utilize steam pressure to make espresso. The drawback is that the boiler that produces steam also raises the temperature of the water until it reaches boiling and can result in over-extraction. Additionally, these machines frequently have to rebuild their pressure between cups, which takes time and energy.

Many espresso machines make use of either a vibration or rotary pump. A vibration model employs a vibrating disk to generate pressure, while a rotary model pushes hot water through the ground at a fast speed. Both machines can make excellent espresso but rotary machines are more stable, quieter and less likely to break down.

The Boiler

The boiler is the one that heats the water to a temperature that is ideal for extraction. The steam that is produced reaches the portafilter containing ground espresso beans and gets funnelled down into the cup. The steam causes pressure to push through the grounds of the coffee. This results in a layer of crema that is then poured over. This is one of the hallmarks of a great espresso.

There are three kinds of espresso makers, and they differ in the kind of pump they use and the degree of heat that the espresso coffee makers is. There are many ways to control the amount of brew, as well as the size of cup that can be produced by the machine.

The first espresso machines were steam type. They employed one boiler to create both brew and steam, however the pressure they were able to generate was low - only two bars of atmospheric pressure at the most. This resulted in the coffee tasting burnt and bitter. The modern espresso machine was developed by the Milanese producers Luigi Bezzerra & Desiderio Pavoni.

The most common espresso machine is a semiautomatic one with an electric pump. When people think of espresso machines, they picture these machines. Semi-automatic machines require you to grind and tamp the beans by yourself however the pump controls the flow of water and pressure. This is a great compromise between the human touch and mechanized accuracy.

The Filter

Espresso machines typically have a filter that separates the grounds of coffee from hot water. The filter is also a vital component of the machine's temp control, since it stops overheating.

It also enhances flavor, as a filter allows for a longer bloom phase. This lets the beans let their nuances out, and also allows for better extraction.

It is important to remember that even the best espresso machine under 200 filter can produce a bad cup of coffee. The quality of the beans, and the extraction, are still very important.

It's in this area that the magic occurs. This is what makes espresso taste so delicious. The grouphead (also called the brewhead) is where you put the portafilter - the thingy which you put the grounds of coffee into when making espresso.

In a steam-driven espresso machine hot water is heated in an airtight tank to produce steam, which is then pushed through the grounds at high pressure. These machines are less expensive and are easier for the user to maintain than pumps-driven models. They are however limited to create the ideal brewing conditions as they only operate with 1-1.5 bar of pressure. The perfect shot requires 9-10 bars.

In recent years, espresso machines powered by a compressed air pump have become increasingly popular. They utilize an air compressor to push hot water through the ground, and Machine espresso are more mobile than steam-driven electric espresso machines.