How to choose the espresso machine? how to distinguish the espresso machine from the good one?

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Now more and more people can't live without coffee in their daily life, so there must be a lot of friends who will consider it.

Espresso is mellow and rich in oil, and one of the factors that determine the amount of coffee oil is the extraction pressure. Generally speaking, the semi-automatic coffee machine can reach the standard pressure value (9bar) for extracting coffee.

How to tell whether a coffee machine is good or bad:

First, from the way of heating water, there are two main ways: 1. Heating block heating; 2. The boiler is heated.

1, heating block:

The heating mode of the heating block is mainly for small models of household machines, and its principle is similar to that of electric water heaters.

Disadvantages: due to structural reasons, the water temperature is not stable.

(ps: not advertisements! Hui family coffee machine because of the adoption of double heating block, three heating block technology, in terms of its price, it is really gratifying domestic products. The author tried 310s at the Shanghai International Hotel Exhibition in 14 years, and the effect is as good as that of the coffee shop.

2, boiler heating:

Almost all commercial coffee machines now use the same method. The boiler heating is divided into: ① single boiler ② master boiler ③ double boiler and multi-boiler.

Sub-master boiler

① single boiler:

It is common in household models.

Disadvantages: low efficiency, because the temperature of making espresso ranges from 90 to 98 ℃, and the temperature of steam is above 100, so it can not be extracted and milked at the same time, so it is gradually abandoned.

A dragon

② sub-master boiler (and E61):

When it comes to son-mother boilers, we must talk about E61. In 1961, the E61 coffee machine launched by FAEMA Pegasus has cross-era significance for coffee machines: ㈠ established the structure of heat exchange mother boiler (now most middle and low-end commercial coffee machines adopt this, practical, cost-saving, and will introduce the principle later); ㈡ established the brewing head specification E61 of most commercial coffee machines (58mm powder bowl, handle in contact with coffee maker) ㈢ E61 also achieves simple pre-soaking and heat preservation of the head.

Faema E61

Heat exchange principle: heating the water of the large boiler, the cold water is heated through the coil in the large boiler to extract coffee, and the large boiler outputs milking steam.

Disadvantages: because the heated water is still recycled when it is not extracted, the water temperature in the coil is actually higher than the set temperature (experienced baristas will release part of the water before extraction and try not to use hot water in the boiler. One is that repeated heating is unhealthy, and the other is that once the boiler enters cold water due to insufficient water, the extraction water temperature may not be enough for a period of time). Moreover, due to structural reasons, it is difficult to stably control the extraction water temperature, and the optimum extraction water temperature for coffee beans with different roasting degrees is different.

Heat exchange structure

③ double boilers, multi-boilers (and PID temperature control):

Double boilers include one steam boiler and one coffee boiler, while multiple boilers have different brewers with independent coffee boilers, and most of the coffee machines with double (multiple) boilers are added to the PID temperature control system. In this way, the disadvantage of uncontrollable water temperature of the son-mother boiler is solved, and of course the price is more expensive.

La Marzocco gs3

Talk about PID temperature control system:

The full name of PID is Proportional integral derivative, which is literally translated as proportional integral derivative.

The traditional thermal insulation is based on the temperature value as the condition to trigger the heating, such as starting the heating when the temperature is lower than 85 ℃; and the design of the son-mother boiler is simply controlled by air pressure, which leads to a delay in heating and a large temperature difference in water temperature (for example, fluctuating between 88 and 95 ℃).

The PID temperature control system not only measures the real-time water temperature, but also calculates the rate of change of the water temperature. Reaching the set temperature will change the heating power to maintain a relatively constant temperature in the form of pulses (for example, fluctuations between 93-93.8 ℃).

Ps: the larger the boiler, the greater the relative constant temperature capacity and the stronger the continuous production capacity. PID temperature control is practical and the price is ordinary, because the 600 yuan bonavita hand flushing pot is also equipped with PID temperature control system.

Second, provide extraction espresso pressure pump, the main two kinds: 1, vibration pump; 2, rotary pump.

1, vibration pump: the principle is similar to the pump, many household machines marked "maximum 15bar or 20bar pressure" is this.

Disadvantages: loud noise, unstable pressure.

2. Rotary pump: the principle is that the turbine rotates and the pressure is stable, which is used in most commercial coffee machines on the market.

Ps: some high-end pressure swing coffee machines on the market still use rotary pumps, but the extraction pressure will be changed directionally during the extraction process, rather than the conventional 9bar, which is completely different from the unstable pressure of the vibration pump.

Third, other functions added:

1, set water output; 2, set pre-soaking time; 3, display extraction time; 4, variable pressure extraction; 5, cooking proportion technology, and so on

1, set water output: you can set automatic extraction water (ml), if you keep the same amount of grinding powder each time, it is equivalent to relatively maintaining the gouache ratio (volume / weight) of each cup of espresso, which is very practical, for the production efficiency and quality is greatly improved, and the technical price is common (common in digital newer models).

2, set pre-soaking time: pre-soaking refers to the first low pressure (1~3bar) less water to make coffee pressed powder moist, coffee powder water absorption expansion, the extraction space is filled with powder, reducing the channel effect caused by uneven extraction; another advantage is the same as hand-brewed coffee, the release of carbon dioxide, improve the extraction efficiency and reduce the lack of extraction caused by too fresh coffee beans. The practicability is high, and the technology price is ordinary (still common in the newer digital models).

3. Display extraction time: it is practical and useful for coffee quality control, and the technical price is very low (still common in digital newer models).

Astoria plus 4 you

4. Pressure swing extraction: break through the traditional 9bar extraction and change the extraction pressure. For example, synesso hydra's "extraction pressure curve", for example, first extracted with 2bar for a few seconds, then extracted with 5bar, 9bar, and finally ended with 5bar extraction, the longo can still be extracted for a minute. The technology content is high, and the technology price is expensive.

Synesso

5, brewing proportion technology: different from the set water output, the technology of brewing proportion can weigh the weight of coffee powder inside the coffee machine, and can weigh the weight of espresso on the outside, keeping the ratio of powder to water consistent (weight / weight). In practicability, the technology content is high and the technology price is expensive.

6. Other features, such as Kees speedster's non-screw design, Modbar's space-saving fashion appearance, Slayer's 0-12bar transformer, Sanremo opera's Bluetooth phone control, and so on, are specific features of some high-end and expensive brand machines, and their practicality varies from person to person, but the price, um, is only available to Tuhao.

Kees speedster

Modbar

Summary:

① boiler and rotary pump are the distinction between professional and non-professional coffee machine (after consideration, I still think Huijia's multi-heating block design can be an exception)

The basic grade of coffee machine is determined by the size of ② master boiler or double (multi) boiler (must be equipped with PID temperature control) and the size of boiler.

Other functions of ③ bring more benefits to the efficiency and quality of coffee production.

END