For more knowledge about specialty coffee, please pay attention to: Front Street Coffee (Frontsteet Coffee）
Many friends reported that they bought it themselvesItalian blended coffee beansAfter grinding it back and extracting it, I couldn't extract the oil. The extracted concentrate generally had no taste and felt very watery. When this problem occurs, the baristas on Front Street will suggest adjusting the grinding size. This article will talk about how to determine the Italian styleEspresso grind size。
First of all, before we adjust the grinding degree, we need to choose freshly roasted ones.espresso beans
First of all, choose products from professional coffee roasters that clearly indicate the roasting date (not the expiry date or shelf life), have a good brand reputation, and emphasize fresh roasting.
In addition, good coffee packaging bags usually have a "one-way exhaust valve" (a small button-shaped hole on the top of the coffee bag) design to allow the coffee beans to discharge naturally occurring carbon dioxide. Aim the one-way exhaust valve at your nose, gently squeeze the coffee bean bag, and smell the squeezed out gas. If it has a charming and fragrant coffee aroma, the freshness is not a problem. On the contrary, if the smell is not strong enough or even smells of stinky oil, it means that the bag of coffee has already deteriorated and stale, and you should avoid buying it. Every package of coffee beans sold by FrontStreet Coffee is packaged with a one-way exhaust valve to ensure that each package of coffee beans reaches the buyer in the freshest state.
Choose to be ableGround espresso powdergrinder
For commercial use, you can purchase an Italian-style grinder. The biggest features of Italian coffee grinders are extremely fine grinding, fast speed, large cutterhead, and evenness is a hard indicator to judge whether the coffee grinder is good or not. However, Italian coffee grinders usually cannot achieve the extremely fine grinding degree of other coffee grinders. If you want a grinding fineness for espresso coffee at home, we should choose a grinder with a flat blade. FrontStreet Coffee currently uses the Pegasus 600N flat knife grinderMachine ground espresso coffeecoffee powder.
Why does Front Street recommend grinders that use flat blades?
The working principle of the flat knife grinder: It consists of two upper and lower cutterheads. The base is fixed on the motor. When the motor starts, the upper and lower cutterheads rotate to produce cutting action. When the coffee particles fall from the middle, the rotating cutter at the bottom will rotate the coffee beans to the periphery, pushing the coffee beans into the toothed cutter part for grinding. The upper and lower cutterheads of the flat knife are arranged in a parallel manner, so the coffee beans need to rely on the rotation of the bottom cutterhead to push the coffee beans into the cutterhead. Therefore, the weight of the coffee beans placed on it will affect the uniformity of the coffee beans entering the cutterhead, thereby affecting the uniformity of grinding. In addition, due to the pushing, the number of collisions between coffee beans increases, which in turn leads to an increase in the proportion of fine powder produced. this is commonFlat knife grinder grindingThe particle uniformity is slightly poor, due to more fine powder. The coffee liquid concentration and extraction rate are increased in a short period of time, so that the coffee aroma can be significantly improved in a short period of time.
Advantages of a flat-knife grinder: Clear positioning, product quality is proportional to the grade of the grinder and the diameter of the grinding disc. Disadvantages: The uniformity of the grinding particles is slightly poor, and there are more fine powders. Because the blade of the flat-knife grinder cuts the coffee beans at will, it is easy to cause insufficient or over-extraction of the coffee powder during brewing. In addition, the friction of the flat knife will generate heat. Especially when the flat-knife grinder is working for a long time, there will be obvious burnt and bitter taste.
What is the grinding principle of the grinder?
When the coffee beans enter the grinder, the blades in the grinder crush the beans into powder. The smaller the blade-to-blade distance, the coffee beans will be ground into smaller particles. The finer the ground particles, the tighter they are and the more difficult it is for water to pass through, thus greatly extending the extraction time. On the contrary, if the distance between the blades becomes larger, the ground particles will become rougher, and the water flow will pass through more easily, and the extraction time will become faster.
How do we decide what’s right for us?Concentrator Grinding Degree？
Front Street is adjustingGrinding degreeWe will first use the golden ratio of concentrated extraction and the golden time to determine a parameter: a ratio of 1:2 (20g powder extracts 40ml coffee liquid) and the extraction time is between 25 and 28 seconds. Then we will judge the adjustment of the grinding degree through observation and tasting.
If the grinding degree is too coarse, the water flow will pass through the powder bowl too fast, the water flow will be thick, the extraction will be shallow, the color of the oil will be white, and the flavor will be sharp and sour. Because the extraction is incomplete, only the acidic substances on the surface and easy to extract are extracted. If the grinding degree is too fine, the filter holes will be clogged, the water will not flow out or the water column will be too thin, the oil will be dark in color, the surface will be over-extracted, and the inside will be under-extracted, which will appear sour because of insufficient sweetness, and then burnt, bitter, and miscellaneous flavors will appear.
If we want to more rigorously test whether the concentration reaches the standard value, we can first calibrate the concentration tester. Most espresso concentrations are between 7% and 12%. Clear the standard with pure water. Then stir the extracted Pour over(V60) coffee, extract the coffee liquid with a titration test tube, put it into the coffee concentration tester, press the measurement button, and try to measure the value multiple times until the value is stable.
Front Street Coffee (FrontStreet Coffee) Extraction parameters of espresso
make espresso We use the Front Street classic Italian blended coffee, which is a recipe made from three origins: Brazil, Indonesia, and Vietnam. It has the caramel aroma of American coffee and the wild tonality of Asian coffee. In order to maximize the mellow aroma of coffee, and also hope that everyone can easily extract the rich and dense coffee oil, Front Street Coffee adopts deep roasting. It is very suitable for making American style diluted with water or latte with milk. You can purchase and place an order at the Front Street Taobao store or the Front Street Tmall flagship store.
Front Street concentrated extraction parameters:
Grinder: Galileo Q18
Grinding degree: 2.0 grid
Pressure: 10 bar
Temperature: 94 degrees Celsius
Time: 25~30 s
Amount of powder: 20g (double espresso)
Extraction volume:40mlExtracted espresso flavor: smooth taste, medium body, smells obvious of chocolate accompanied by a faint caramel aroma, and has a smooth taste of nut cookies in the mouth, which is rich in powder.
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
