[hand flushing knowledge] should the steaming time of 30 seconds be calculated from or after water injection?

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The fans who came to visit the store today asked the editor a question: is the steaming time calculated from the beginning of water injection, or is it timed after water injection?

Sure enough, it is a problem of blackening under the light. Most of the time, the editor will advise everyone to steam for about 30 seconds, but forget to explain when the clock should start.

Well, today, the editor will come to mend and explain to you the problem of "stuffy steam timing".

First of all, the editor first explains: all the videos, cooking demonstrations and suggested parameters recorded by the editor are timed from the end of water injection. Take our most commonly used 15 grams of powder for example, generally about 30 grams of water is injected, and the steaming time is 25-35 seconds.

If it is an unconventional method of steaming and injecting water (it seems that we haven't talked about it yet). ), it will generally indicate how much time it takes to inject water + how much time to steam. In any case, the time of the water injection process will not be counted as the steaming time. Water injection is returned to water injection, and stuffy steam is returned to stuffy steaming, and the time of the two is calculated separately.

The above is the normal process of stifling water injection demonstrated by Xiaobian. As can be seen from the whole video, the amount of water injected by Xiaobian is 30 grams, and the time will be about 10 seconds. That is to say, 10 seconds of water injection + 30 seconds of steaming = 40 seconds; if the timing starts from the beginning of water injection, then 10 seconds of water injection + 20 seconds of steaming = 30 seconds will be less than my default 30 seconds of steaming.

So, the question is, what is the impact of the 10-second steaming time on the extraction of coffee?

Let's prove it with an experiment.

The difference between steaming for 20 seconds and steaming for 30 seconds

Experimental variety: [Yemeni Mokamatari], baking degree: medium baking; baking date: June 28, bean cultivation period of 11 days, has basically entered the best flavor period.

Experimental technique: filter cup [smart cup], when steaming and injecting water, it is placed on the sharing pot and flows up and down to simulate the normal filter cup steaming and injecting water. After steaming, the sharing pot is removed, and the piston is closed to become an immersion extraction, so as to reduce the influence of the deviation of water injection in the later stage on the extraction.

Experimental parameters: 15g powder, total water 225g, water temperature 90 ℃, immersion and extraction for 1 minute and 40 seconds, then re-placed on the sharing pot to filter, the total extraction time was 2 minutes. (the time starts from the end of water injection.)

The experimental group ① steamed for 20 seconds.

This group simulates 30 seconds from the beginning of water injection, 30 grams of water injection, 10 seconds of water injection + 20 seconds of steaming, and takes away the sharing kettle after steaming and injects 195 grams of water.

② of the experimental group was steamed for 30 seconds

This group is simulated from the end of water injection and then start timing for 30 seconds, water injection for 30 grams, water injection time for 10 seconds + steaming for 30 seconds. After steaming, remove the sharing pot and fill it with 195 grams of water.

Analysis:

1. First of all, it can be seen from the surface of steaming that when steaming for 20 seconds, the surface of the powder layer remains relatively glossy and bright (reflective), and only gradually becomes matte after 30 seconds. In fact, according to the principle of steaming, the exhaust of coffee powder needed by steaming is needed to promote uniform extraction in the later stage. when the surface of the powder layer is bright, it means that the powder layer is still expanding or the exhaust is still going on, and only when the surface begins to become matte, it is proved that the water has begun to seep down, the surface layer has reduced gas emissions, and there is not enough support to keep moisture on the surface of the powder layer. This is the perfect end of the steaming process.

On the left is the experimental group ①, on the right is the experimental group ②; from the appearance, basically can not distinguish.

2. Taste comparison after brewing:

① 's [Yemeni mocha] has obvious flavors of nuts, chocolate, spices and red berries, with a light tea at the end and medium thickness.

② 's [Yemeni mocha] is also full-bodied with nutty, chocolate, spice and red berry flavors, with a slightly stronger tail than ① and a slightly thicker Body.

In fact, from the above taste, we can see that the difference between steaming for 20 seconds and steaming for 30 seconds (that is, timing from the beginning of water injection and then after water injection) is not as big as imagined.

Summary:

Generally speaking, as long as the water temperature and grinding are correct, the steaming operation is not wrong, and the slight deviation of the steaming time (within 10 seconds) is not as obvious to the results of the whole hand flushing as everyone thinks. even if the two cups are not compared together, you may not be able to drink the difference. The real purpose of this experiment is not to let everyone pick the steaming time of about 10 seconds, but to carefully observe the surface state of the powder layer during steaming to judge the end time of steaming. After all, different baking date, water temperature and grinding degree will affect the effect and duration of steaming. The suggestion of 30 seconds steaming time given by the editor is only aimed at the best taste period. The error is allowed to be a few seconds before and after.

If the coffee beans have been kept for quite a long time (for example, more than a month), then the coffee powder should have entered the end of exhaust (that is, it will not expand, and the water will soon collapse after injection). At this time, you don't have to stick to the suggestion of steaming for 30 seconds. Once you find that the surface of the powder layer has changed from reflective to matte, you can immediately end the steaming and move on to the next stage of water injection.

After all, there is no standard or definition of steaming. In the process of learning hand flushing, when we need to refer to the film or data, don't forget to observe whether the steaming time is calculated from the beginning of the water supply or after it is given. And adjust to their own habit of steaming time. In the editor's observation, in many of the god's cooking videos, the steaming time is calculated from the end of water injection, so the editor also suggests that everyone use this definition as the standard for sharing, and some genres are calculated from water injection. at this time, we will reduce the water injection time, you can convert to the actual steaming time.

All right, that's all for this issue of sharing. For those of you who still have questions about steaming, you are welcome to leave a message to the editor. If there are any mistakes or inadequacies, you are welcome to leave a supplementary message for discussion.

Looking forward to the next issue of knowledge sharing! Let's work together to improve our professional level.

[previous review]

Daily test | how much influence does the amount of steaming water have on coffee extraction?