Should I sift out the fine powder in the coffee? What should be done with the fine powder sifted out from the coffee powder?

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Coffee grinding has a great impact on the flavor of a cup of coffee, even the best bean grinder can cause fine powder, such as the hand mill or electric mill used in ordinary families is a bit unsatisfactory in grinding. Qianjie Coffee will share the brewing scheme with too much fine powder.

How is the fine powder produced?

In general, bean grinders cut coffee beans by rotating two cutters alternately, such as ghost tooth cutters, that is, two ghost tooth shaped cutters are grinding at high speed, although the characteristic of ghost teeth is to cut coffee beans into countless small round particles as far as possible, so that the particles tend to be uniform.

But also because of this feature, there is an extrusion effect between the two cutters, which will "crush" the coffee beans and burst some fine powder.

Generally speaking, coffee particles with a particle value of less than 250 microns are called fine powder. So one of the criteria for judging whether a bean grinder is excellent or not is whether the grinding rate of fine powder is low.

What is the effect of fine powder on making coffee?

Too much fine powder will block the drain hole of the filter cup, resulting in a slow flow rate and the risk of over-extraction. And the particle value of fine powder is smaller than other coffee particles, the extraction efficiency will be higher than normal coffee particles, resulting in local (fine powder) over-extraction of coffee, resulting in bad flavor.

So just get rid of all the fine powder, this method is really feasible, brewing coffee is much cleaner, but you will find that it is too clean and even a little hollow, similar to the feeling of lack of flavor.

Qianjie Coffee also reached this conclusion through a group of comparative experiments, which were compared by normal brewing and sifting out the fine powder.

Front Street Coffee Asalia AA, Kenya

Country: Kenya

Producing area: Sika Thika

Processing plant: Asali honey processing plant

Altitude: 1550m Murray 1750m

Rating: AA TOP

Variety: sl-28,sl-34

Treatment: 72 hours washing

Baking degree: shallow baking

Cooking parameters

Powder quantity: 16g, if sieving powder, 16g after sieving

Powder / water ratio: 1:15

Water temperature: 91 ℃

Degree of grinding: normal hand grinding (the pass rate of No. 20 screen is 80%)

This time, use staged brewing, first inject 30g of water for steaming for 30 seconds, at this time the coffee expands more plump. The center of the second section is filled with 120g water in a small circle. The water injection height is 5cm, the strength is gentle, and it is not necessary to stir. When the water level drops to 1 stroke 2 of the silt layer, the third stage of water injection begins, and the water injection in this section gently circles outward from the center, and the flow is about 4g/s until the injection is finished at 240g. The coffee liquid in the filter cup is finished after dripping, and the extraction time is about 1 minute and 50 seconds.

The comparison of flavor is as follows

Normal: it has the flavor of virgin fruit, grapefruit peel, cocoa and black tea, but it is relatively light as a whole, and miscellaneous flavors will appear when the temperature drops.

Sieve powder: bright, clean and transparent fruit sour, virgin fruit, empty.

As to whether the fine powder should be screened out, Qianjie believes that the appropriate fine powder can fill the richness of flavor, but the fine powder is easy to produce miscellaneous smell caused by extraction. for this, Qianjie recommends a way to deal with this problem.

Cooking parameters

Powder content: 16g

Powder / water ratio: 1:15

Water temperature: 91 ℃

Degree of grinding: normal hand grinding (the pass rate of No. 20 screen is 80%)

Fine powder rate: 12.5% (< 250%) / 2g fine powder

Filter cup: V60

1. Sift out the fine powder with a 250 micron sieve, pour in the coffee powder after sifting out the fine powder, and pour in 28g of twice the amount of water for steaming for 30s.

two。 After the end of steaming, the second stage of water injection was carried out, and 120g water was injected outward in the center.

3. Immediately after the end of the second stage of water injection, pour in the fresh 2g fine powder, then rinse the fine powder down with a water column until the water injection reaches 240g. After the coffee of the filter cup flows into the sharing pot, remove the filter cup and finish the extraction. The total extraction time is 2 minutes.

This brewing method can retain the flavor of the fine powder without extraction, making the flavor of the coffee richer. If the small partner's bean grinder produces more fine powder, you can use this method.

For a bean grinder with more fine powder, adding fine powder may be a good choice. After all, the fine powder is easy to be extracted quickly in a short time, and the fine powder has already been extracted before other coffee powder has been extracted in the filter cup.

However, if you sift out the fine powder and brew it, it is easy to get a cup of coffee with weak flavor, or even plain. So you can try to pour in the fine powder before the second stage of water injection.

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