Is the breeding period of coffee beans really so important? Does raising beans have a great influence on the flavor of coffee?

"Coffee beans produce a lot of gas after roasting, and these gases will be slowly discharged out of the coffee beans over time." Friends who often buy coffee beans should notice that if they are about 1-2 days away from the baking date, the coffee bags are still dry and shrunken, and if they are not opened for too many 4-5 days, the coffee packaging is bulging, and this is the exhaust of coffee beans.

The baking dates from the left are May 28th, 27th, 25th and 20th respectively.

And what we call the bean cultivation period is to use a week or so to discharge a large amount of active carbon dioxide gas out of the body and retain part of the gas to stabilize the coffee beans. So do freshly roasted coffee beans need to be kept before they can be drunk? Do two sets of comparative experiments on the previous street to see the difference.

Raise beans VS does not raise beans

First of all, in Qianjie, Kenya AA coffee beans were used as the representative of medium and shallow roasting, and the coffee beans roasted for 7 days were compared with those roasted for 1 day.

Cooking parameters

Powder content: 15g

Ratio of powder to water: 1:15

Degree of grinding: 80% pass rate of No. 20 standard screen (medium and fine grinding)

Water temperature: 91 ℃

Filter cup: V600001

Bean group: first inject 30g of water and steam for 30 seconds, you can see that the "coffee burger" bulges regularly in the process of steaming, and there are no big bubbles. Then 100g of water is injected into the second stage, and delicate coffee foam emerges. After 95g water is injected into the last stage, the coffee liquid in the filter cup is removed and the extraction is finished.

No bean group: first injected with 30g of water for 30 seconds, many large bubbles appeared in the process of water injection, and a large bubble appeared continuously on the surface of the "coffee burger" after the completion of water injection. Then 100g water is injected into the second stage, and there are still air bubbles gushing from the bottom in the process of water injection, and the coffee foam on the surface is slightly rough. After 95g water is injected into the last stage, the coffee liquid in the filter cup is removed and the extraction is finished.

Then we will cook the medium and deep baking group represented by Brazilian red bourbon coffee beans. Or use the coffee beans of 7 days after baking and the coffee beans of 1 day after baking respectively to compare.

Cooking parameters

Powder content: 15g

Ratio of powder to water: 1:15

Degree of grinding: 75% of pass rate of No. 20 standard screen (medium grinding)

Water temperature: 88 ℃

Filter cup: V600001

Bean group: first inject 30g of water and steam for 30 seconds, the coffee powder "coffee burger" bulges regularly in the steaming process, and the shape of the "hamburger" is more beautiful because of the deep roasting. Then 100g of water is injected into the second stage, and the dark brown coffee foam gushes out from the middle. At the end of the water injection, the foam color changes to golden yellow, and the foam oil is rich as a whole. After 95g water is injected into the last stage, the coffee liquid in the filter cup is removed and the extraction is finished.

Non-soy group: first injected with 30g of water and steamed for 30 seconds, the coffee powder expanded rapidly after meeting the water, during which atmospheric bubbles emerged, and during the steaming period, two pores appeared on the surface of the "coffee burger" and continued to produce large bubbles. Then 100g of water is injected into the second stage, and when the water is injected, the coffee foam emerges and covers the surface quickly. The coffee foam on the surface is slightly rough, but no atmospheric bubbles appear. After 95g water is injected into the last stage, the coffee liquid in the filter cup is removed and the extraction is finished.

Comparison of results

In the process of brewing, the difference between medium-shallow roasted coffee beans and medium-deep roasted coffee beans is very obvious. In the case of no beans, a large amount of gas gushes out after meeting water, which increases the density difference in the powder layer. Medium-shallow roasted coffee beans have not completely discharged gas within 30 seconds of steaming time, so large bubbles will appear during the second stage of water injection. After the bean cultivation period, the coffee beans are more stable when they are brewed.

And then from the flavor to distinguish whether to raise beans or not how much the change. Through the comparison of the two groups of coffee, there is no significant difference in taste. In terms of aroma, the aroma will be richer after raising beans. After tasting the non-soy group, the throat will feel dry and "dry". This is also because coffee beans are prone to "hot and dry" feeling after rapid cooling after high temperature roasting, and the state of coffee beans will stabilize and reduce the "dry feeling" after the bean cultivation period.

Generally speaking, Qianjie still advises everyone to get freshly roasted coffee beans, do not rush to try, first rest and store for a week or so before tasting, it is still necessary to raise beans.