The key points of grinding coffee beans: the relationship between the degree of grinding and the change of coffee taste and coffee extraction tools

For professional baristas, please follow the coffee workshop (Wechat official account cafe_style)

The key points of grinding coffee beans

Once the coffee bean becomes powdered, it will oxidize rapidly because of its larger contact with the air, and sometimes it will smell sour because of the oil it contains, so proper grinding is also related to the success or failure of a cup of coffee. Grind the coffee before brewing in order to retain the aroma of the coffee. The key points in grinding are as follows:

1. The degree of grinding should be average.

two。 No heat can be produced during grinding

3. Can't produce fine powder.

4. Select the degree of grinding suitable for extraction tools

The relationship between the degree of grinding and the change of coffee taste

The finer the grinding degree, the stronger the bitterness, and the coarser the bitterness, the lighter the bitterness. This is the most basic grinding rule.

Coffee grinding degree

Roughness

Fineness

The surface area of the coffee shop

Small

Big

Extractive component

Less

Many

Coffee concentration

Light

Thick

Bitterness present

Weak

Strong

Because fineness grinding increases the contact surface with air, in addition to accelerating the speed of oxidation, once combined with water, the dialysis speed will be several times higher than that of rough grinding. At this time, the adjustment of time and water temperature by the cooking staff becomes particularly important. No matter which cooking method is used, as long as we pay attention to the principle that the water temperature is directly proportional to the grinding thickness and inversely proportional to the heating time, there will not be much problem.

Relationship between Grinding degree and Coffee extraction tools

Different coffee brewing utensils need different grinding degrees, too coarse particles can not extract the taste, too fine and easy to over-extract, resulting in bitter taste, so the suitable extraction can extract the good ingredients of the coffee completely, and the inferior substances are retained in the fiber. in general, the shorter the brewing time, the more the coffee powder must expand the surface area to contact with the water, and the finer the particles are needed. On the contrary, if the cooking time is prolonged, the larger the grinding particles must be, the rougher the grinding particles must be, so as not to extract unnecessary impurities. For example, a fast-extracted Espresso requires extremely fine grinding like a fine powder, and a rough grind is required in order to fully infiltrate the coffee to release its aroma.

For example, the filter paper or plug-style brewing method, because the extraction time is relatively short, about one or two minutes, the coffee beans have to be ground a little finer than the French filter kettle. The extraction time of the French filter kettle is about three or four minutes, so it is appropriate to grind the coarseness. If the grinding is too fine, it is easy to drink coffee grounds and have a bitter taste. In other words, the longer the extraction time, the thicker the coffee beans will be ground, so as not to cause excessive extraction and bitter taste; the shorter the extraction time, the finer the coffee beans will be ground, so as to avoid insufficient extraction.

Coffee grinding degree

Suitable cooking tools

Fineness grinding

Mocha pot, espresso machine

Moderate grinding

Filter paper dripping method, air stopper method, flannel dripping method

Roughness grinding

Light dripping filter pot, dripping coffee machine

Grinding tool

Bean grinders are generally divided into three types:

1. Manual rotary bean grinder-suitable for hand measuring.

2. Electric bean grinder-suitable for more use.

3. Professional bean grinder-suitable for commercial use.

Cleaning of bean grinder:

The most troublesome part of using the bean grinder is probably the cleaning work. The general basic maintenance work is as follows:

1. First carefully wipe the appearance of the bean grinder.

2. Clean up the exit of the coffee powder.

3. If the utilization rate of the bean grinder is very high, it is best to take the bean grinder apart and clean it carefully every week.

Coffee beans contain oil, so you must wash them regularly, otherwise the oil will accumulate more and more, and it will produce a strange smell over a long period of time, even the most advanced and fresh coffee beans will taste bad.