[Italian concentrated production skills] do you need to put some water on the boiling head before extraction?

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Friends who have seen the Italian concentration process should have seen this operation more or less, that is, baristas will release some of the front-end water before buckling the handle, but in fact, there are many people in the actual operation. Will ignore this step. Therefore, today I would like to discuss with you the significance and necessity of this front-end action of releasing water.

First of all, why release water?

After flipping through books and discussing with our peers, we probably found the following reasons:

◎ rinses the coffee grounds left on the filter screen from the previous cup and flushes the filter cup on the handle to ensure the taste and quality of the coffee.

The water in the front part of the ◎ cooking head is unstable (the mother pot may be too high, and the double boiler and multi-boiler may be too low). The discharge of the water is beneficial to the stability of the extraction water temperature.

Analysis:

◎ washed away the coffee grounds left on the strainer from the previous cup:

This is the reason for most people. To be honest, I don't think most people can appreciate the impact of washing on the quality of one or two cups, but this is a cumulative process-if you don't pay attention to the washing of each cup, dozens or even hundreds of cups of coffee machines a day will be greatly affected.

Of course, not all baristas do that even in Italy. In fact, it is not necessary to wash the handle, because if it is not wiped dry, the water will drip randomly, and it will be faster to clean the handle directly with a cloth or brush.

Is there any deviation in the water temperature in the front section of the ◎ (from the cooking head to the boiler)? This should refer to the old coffee machine without siphon circulation system, now most models have siphon circulation system, generally there will not be such a problem. In addition, it takes at least 10 to 30 minutes for the water temperature in the front part of the cooking head to rise or drop to a serious extent (depending on the type of machine). ), therefore, whether or not to release water, the greater impact should be the temperature of the water distribution network, rather than the temperature of the water.

You can do the following tests: when continuous brewing and waiting for 10, 15, 20, 25 or even 30 minutes, press the brewing button to receive water for about 15 seconds, and measure how much the water temperature changes from the head. You can probably know whether it is necessary to put water in the front end of your coffee machine.

From the above, it can be seen that it is not completely superfluous to put water in the front, especially before brewing after the coffee machine has been set still for a period of time, it is very necessary to do it, but it does not matter when brewing continuously. The key is to look at the size of the boiler and power of the coffee machine. For example, the sub-boilers of some minicomputers are only about 300 to 360 kilos each. If they are continuously brewed and water is released every time, it may lead to insufficient heating of the water temperature and affect the extraction. Even increase the loss of pumps and solenoid valves. Of course, if you are baristas who have strict requirements for product quality and hygiene, you'd better not be lazy.