Italian coffee channel effect What is the channel effect Italian concentrate extraction

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What is the channel effect?

Because water is inert, it will choose the path with the least resistance when it passes through the coffee powder.

Coffee powder is evenly arranged, and it can be evenly extracted by water when it is extracted by a coffee machine.

There are gaps in the arrangement of coffee powder. when extracted by a coffee machine, water will choose to pass through more empty places, while coffee powder in some places will not be extracted by water, resulting in excessive extraction of some blocks with more water. less extraction is insufficient.

What is the cause of the gap in espresso?

Bean grinder: bean grinder due to the grinding uniformity / shape is too low so that the coffee powder can not be very well together, there are large and small coffee powder.

The process of powder distribution: some of the processes can also create channels.

For example, there are obvious holes in the surface, or after filling and pressing, it is found that there is not enough powder to continue to add powder, and so on.

All these will cause the uniformity of pressed powder to become lower and form a channel.

In fact, the reason for producing the channel, excluding beans, is the uneven distribution of powder, cloth powder and pressing powder.

Therefore, if we pay attention to these aspects when making espresso, we can avoid the emergence of channels to some extent.

Does the channel effect only occur in espresso?

In fact, we are also prone to channel effect when hand flushing, such as injecting water to the edge of the border between filter paper and coffee.

As a result, the injected water flows directly through the filter paper to the sharing pot through the coffee, or there is no uniform circle during the water injection, and the water injection point is on one side, which will also lead to the occurrence of the channel.

There is a significant difference in flavor between the coffee extracted by the channel effect and the coffee extracted normally, and the channel effect still needs to be avoided by ourselves in our daily work.

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