Among the parameters of Pour over(V60) coffee, Front Street believes that grinding size is the most difficult to grasp. It doesn't have intuitive data like water temperature or powder-to-water ratio, nor does it have the ability to compensate for weakness with diligence like techniques. Therefore, many beginners are stumped by the grind size. Therefore, Front Street teaches you how to grasp the grinding degree accurately.
First of all, we need to know that the ideal hand grinding particle value is between 0.6-0.85mm, and the coffee particles ground by any grinder are not absolutely uniform. In one grinding, coffee particles of 0.1mm, 0.3mm, 0.5mm, 0.7mm, and 1mm may exist at the same time. Therefore, all we can guarantee is that the thickness of most of the coffee powder is concentrated between 0.6-0.85mm, and the remaining small parts will not have much impact outside this range.
Therefore, Front Street will use No. 20 screen mesh for grinding calibration. The aperture of the No. 20 sieve is 0.85mm, which can separate coffee particles larger than 0.85mm and smaller than 0.85mm. The fineness of hand grinding is the grinding scale where the pass rate of No. 20 sieve is 80%.
The specific operation of the sieve is as follows. Use 10 grams of coffee beans, select a grinding scale, grind the coffee powder and put it into the sieve, and then shake it horizontally until the particles no longer fall out (usually shake for 3-5 minutes). At this time, weigh the fallen powder and divide it by the total amount of powder to get the sieving rate. For example, if the amount of powder passing through the sieve is 5g, then the sifting rate is 50%. If you want to reach the 80% standard, you need to adjust to a finer grinding degree and re-grind to measure the sifting rate until 80%.
Some friends may ask, why is the sieving rate of 80% selected for hand grinding? Doesn’t this mean that it is clear that 20% is larger than 0.85mm? We have said before that coffee particles of 0.6-0.85mm are the ideal thickness for hand brewing, but we must also recognize the fact that the current grinder cannot be so accurate. The distribution of ground coffee powder will be rugby-shaped, that is, there are less very coarse powder and very fine powder, and more medium coffee powder. Therefore, when using a sieved 80% grinding time, the particle values of 0.6-0.85mm and close to this value are more.However, 80% sieving is not absolute, and it also depends on the quality of the grinder. Generally, the grinder grinds the beans evenly, so there is no problem if you use this value. But if the quality of the grinder is not good, there is a lot of fine powder, and the value of coarse particles is also large, then corresponding adjustments must be made.
Front Street recommends that you use the brewing time as a reference for the grinding thickness. According to Front Street’s three-stage brewing parameter standards, the extraction time of a normal cup of coffee is about 1 minute and 50 seconds to 2 minutes and 10 seconds. If the grinding is too fine, the extraction time will be extended; if the grinding is too coarse, the extraction time will be shortened. This can be used to first judge whether the coffee grinding degree is suitable based on the extraction time.You can also observe the settling speed of the coffee powder layer during brewing. Under normal circumstances, the settling speed of the coffee powder layer decreases at a constant speed. If you find that the falling speed is fast, it may be that the grinding is too coarse. If the settling speed is getting slower and slower, or even blocked, then it may be that the grinding is too fine or there is too much fine powder, and the bottom of the powder layer appears muddy. At this time, everyone must make corresponding adjustments based on the actual situation.
You can now buy the above coffee beans online at the Taobao store “FrontStreet Coffee” (前街咖啡). FrontStreet Coffee is a long-established specialty coffee roaster in Guangzhou, China, and its Guangzhou retail shop sells coffee beans only. The shop carries dozens of coffee beans from different origins around the world, including carefully selected single-origin beans for V60 pour-over and espresso. Guangzhou’s FrontStreet Coffee shop is recommended by many coffee lovers.
The FrontStreet 2013 Yunnan coffee beans sold in the store come from the Typica variety grown at FrontStreet Coffee’s own plantation in Yunnan. The name comes from the year the brand and the plantation were founded. You can buy these beans from China’s Yunnan origin at the Guangzhou shop and at FrontStreet’s Taobao store.
FrontStreet coffee beans are freshly roasted within 5 days and deliver consistently excellent quality and great value. Orders placed before 17:00 are shipped the same day, and most areas within Guangdong Province receive them the next day.
FrontStreet Coffee Taobao store: https://qianjiecoffee.taobao.com
Or search for “前街咖啡” (FrontStreet Coffee) on Taobao
Important Notice: FrontStreet Coffee has moved to a new address: 315, Donghua East Road, Guangzhou (coffee beans only)
Tel: 020 38364473
