What do you mean by steaming in baking? Is there a big difference in the flavor of steamed coffee when baking?

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The editor recently read an article in which the term steaming was mentioned. I can't help but wonder, what's the difference between steaming and not steaming when roasting coffee beans? What is the effect on the flavor? So the editor decided to explore.

Steaming SOAK

The steaming in baking is different from the steaming in hand flushing to exhaust the coffee powder, which is a method in baking. Use a small amount of firepower or turn off the fire directly when putting coffee beans into the boiler, and then increase the firepower in a few minutes!

Bean information

The editor chose the bean [Brazilian Red Bourbon] for today's baking exploration. The density of this bean is low, the bean quality is soft, and it is more controllable during baking, which can reduce the error in the baking process.

[Brazil Red Bourbon]

Producing area: South Minas, Brazil

Manor: Veloso

Altitude: 1100 m

Treatment: half-sun treatment

Variety: red bourbon

Baking experiment

This experiment only changed the time of firepower when opening the beans, and other parameters were kept consistent as far as possible.

[curve one fired directly into the bean]

Input temperature: 185 ℃, recovery point: 1: 36 ", 96.5 ℃; yellowing point: 5: 18", 144 ℃; first explosion point: 9: 05 ", 184.8 ℃; development time after explosion: 3: 30"; outlet temperature: 201.4 ℃

The Agrton pink value is 69.8 (left), the Agrton bean color is 75.8 (right), and the Roast Delta value is 6.

[curve 2 steams for 1 minute and then turns on firepower]

Input temperature: 185 ℃; firing to 130 after one minute; recovery point: 1: 46 ", 92.6 ℃; yellowing point: 5: 54", 142.3 ℃; explosion point: 10: 23 ", 186 ℃; development time after explosion: 3: 30"; outlet temperature: 201.2 ℃

Agrton pink value is 64.1 (left), Agrton bean color value is 67.8 (right), Roast Delta value is 3.7.

Cup test comparison

[curve a direct shot into the bean] there are cocoa, caramel, nut flavor, slightly astringent, thin taste.

[curve 2 steaming for 1 minute and then opening fire] with soft fruit acid, with milk chocolate, nuts, caramel, cream flavor, the overall balance.

Analysis.

By comparing the color value and flavor, we can find that Brazil steamed for 1 minute will be more balanced and thicker, while the Brazil without steaming will be thinner and slightly astringent.

Combined with Scott Rao's guess: in a typical 10-12 minutes of baking, coffee beans will not release water at least for the first minute. Part of the coffee bean must reach the boiling point in order to release internal water in the form of steam. Even at the boiling point, water vapor may not be released immediately when it is formed, because the cellulose structure around the steam may be too hard to allow the steam to escape.

Therefore, in the minute when the raw coffee beans are poured and steamed off, the coffee beans will not be dehydrated immediately. Due to heat conduction, the heat in the boiler will be absorbed by the coffee bean surface and transferred to the bean core. At this time, the temperature difference of the bean core surface is relatively small compared with the raw beans without steaming treatment, so in the later stage of baking, the beans will be heated evenly inside and outside. The color difference of bean core is also relatively small.

Moreover, due to the operation of turning off the heat and steaming for one minute, the overall baking time of the beans is prolonged, and the natural dehydration time is also extended, so the flavor will be relatively clean, and it is not easy to be dehydrated and unclean.

Summary

Through this baking exploration, the editor thinks that the coffee baked by steaming will be more balanced and clean as a whole, but whether it is suitable for other beans and so on, we are still exploring …...