What is the function of the espresso extraction pad filter paper? How to improve the uniformity of extraction when making Espresso?

What Qianjie wants to share today is how to make the extraction of espresso relatively uniform. Because it is well known that when making coffee, the uniformity of extraction can affect the texture of a cup of coffee. At the same extraction rate, if the uniformity of extraction is relatively high, then the taste of the coffee will be more balanced, the taste will be more solid, and the aftertaste will be longer; if the extraction is relatively less uniform, then the coffee will have a richer sense of hierarchy, the taste will be divided into primary and secondary, and the flavor will be more distinct.

Most of the time, the extraction of the coffee we drink is not so uniform. Whether it is hand-brewed or Italian, because these mainstream coffee recipes are mainly based on drip extraction. Drip extraction means that hot water flows through the coffee powder layer in a controlled manner and is continuously filtered out while extracting. It is a way to bring out the flavor substances of the coffee powder through short contact. Unlike the soaking type, which uses hot water to wrap the coffee powder throughout the entire process and soak it first and then filter it, the drip filter type will increase the difference in extraction for various reasons. For example, the water temperature and solvent saturation of the powder bed in different positions are different. The extraction efficiency received by the upper layer of coffee powder will be higher than that received by the lower layer of coffee powder most of the time, and the extraction rate of the external coffee powder will be higher than that of the internal coffee powder, so this makes There is a gap in extraction.

Although unevenness has its advantages, it is inevitable that sometimes friends will want to try another style and advantage of coffee, so Qianjie plans to share today how to make the extraction of espresso more uniform. Why only talk about espresso? Because hand-brewed coffee has been shared before, interested friends can find out by searching past articles ~ According to the content shared on the front street, I believe everyone has already understood that the way to make the extraction more uniform is to reduce the differences in extraction between the upper and lower layers/inner and outer layers. If you want to do this, there are actually many methods, such as putting 1 or 2 filter papers on the bottom of the powder bowl, using a higher density powder bowl, or pre-soaking with low pressure before formal extraction.

The addition of these solutions allows more soaking during the extraction process. Instead of letting hot water pass directly through the coffee powder, it will drip out after a short stay. As a result, the contact time between water and coffee powder will be extended. At the same time, the coffee powder on the bottom layer and inside can fully absorb water before formal extraction, and the flavor substances will be better dissolved by subsequent hot water. Relatively speaking, the extraction will be more uniform.

In addition, we can also achieve more uniform extraction by reducing the amount of powder and thinning the powder layer. The thicker the thickness of the powder layer, the greater the extraction difference between the upper and lower powder layers under normal circumstances. After all, their "distance" will be further. By thinning the powder layer, the time for hot water to reach the lower layer is reduced. At the same time, the amount of coffee powder contacted by hot water before reaching the lower layer of coffee powder is reduced, and the dissolved substances are reduced. Then the extraction efficiency of hot water will not drop too much., and the uniformity of extraction can naturally be improved.

Not only that, sometimes an appropriate reduction in the amount of powder can also help the coffee maker better build pressure, increase the stability of extraction, and reduce the probability of triggering channel effects. Therefore, reducing the amount of powder and thinning the powder layer is also an option, but everyone should pay attention to fine grinding while thinning the powder layer to avoid insufficient extraction.

Another thing is that it can be achieved by adjusting the powder-to-liquid ratio. If the espresso you make is American, long black, etc., you can also make the extraction rate more uniform by increasing the extraction volume. For example, use a powder-to-liquid ratio smaller than 1:2, such as 1: 2.5/3. By adjusting the powder-to-liquid ratio and increasing the liquid weight, the coffee powder in the lower layer/inside can also obtain a higher extraction rate, making the extraction more uniform. However, such an approach will test the operator's understanding of extraction. After all, there are many aspects that need to be regulated.

So these are five tips that can make espresso extraction more uniform. Speaking of this, I believe many friends are already curious about the difference between coffee flavors that are not so evenly extracted and relatively uniformly extracted. Qianjie also conducted a small experiment to compare them. The coffee beans used were Front Street Italian Strawberry Candy·Espresso from Front Street Bean List, and the comparison object was espresso. Qianjie used the conventional proportional parameter method to first make a cup of espresso with relatively less uniform extraction. Its performance is just as introduced in Qianjie. The taste is mainly sweet and sour, and then the layers are rich and the flavor is outstanding. You can obviously drink the flavors of strawberry, citrus, floral and cream;

Then I extracted a cup of espresso coffee with low pressure pre-soaked and relatively evenly extracted extract. Similarly, its performance was consistent with that described by Qianjie. The taste was relatively balanced and the sweetness was outstanding. Then the taste would be relatively solid and the flavor would be the same. You can obviously drink the flavors of strawberry fudge, citrus, and cream, but the layers will not be as rich as the former. Both have their own advantages, and there is no distinction between good and bad. So how do you want to make a cup of coffee? Just follow your preferences ~

- END -

Important Notice :

前街咖啡 FrontStreet Coffee has moved to new addredd:

FrontStreet Coffee Address: 315,Donghua East Road,GuangZhou

Tel:020 38364473