What is baking dehydration? What is the effect of baking dehydration time on beans?

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One word is often heard in baking: dehydration.

Coffee beans smell like raw grass before they are roasted, and some dried raw beans even have a bad smell of fermentation! At this time, raw coffee beans generally contain about 10% of the water, which will be the first thing to come out of the coffee beans when roasting begins, so the initial stage is called "dehydration".

The dehydration stage generally refers to the time when the raw coffee beans enter the roaster and enter the boiler until the coffee beans are dehydrated and converted to yellow. In the process of coffee roasting, most of the moisture of raw coffee beans is indeed removed at this stage, but in fact, water is removed throughout the roasting process of coffee beans.

In addition to the removal of water, chlorophyll and anthocyanins in coffee beans and other substances will also be broken down by heating, thus reducing the grass flavor and grain flavor of the beans. Chlorogenic acid, one of the substances that cause bitter dead acid in coffee when the bean temperature reaches above 110 degrees Celsius, will also begin to decompose by heat. Of course, there are some other substances that will be decomposed or formed at this stage, and some of these substances will become the raw materials for chemical reactions that produce flavor substances in later steps.

The structure of raw beans is actually the most complete and heat-resistant during the dehydration stage, so it is recommended to use sufficient heat to heat the coffee beans at this stage, to enlarge the temperature difference between the coffee bean surface and the bean core, so that the coffee beans can absorb calories quickly and take advantage of this opportunity to establish sufficient heat potential energy and the pressure of the bean core.

When baking, each step will have an impact on the flavor of the coffee beans, so let's try what kind of flavor the dehydration time will have on the coffee beans.

We baked [Panamanian Flower Butterfly], [Yega Chuefei Red Cherry] and [Queen of Brazil] respectively. The roaster is Yang 800N:

[Panamanian Flower Butterfly]

Do not extend the dehydration curve

Turn yellow in 4 minutes 50 seconds, start an explosion in 8 minutes 30 seconds, develop 1 minute 45 seconds after an explosion, 194.2 degrees out of the oven.

Lengthening dehydration curve

It turns yellow in 5 minutes, explodes in 8 minutes and 54 seconds, develops in 1 minutes 45 seconds after an explosion, and comes out at 193.5 degrees.

Cup test comparison

Do not prolong the dehydration time: citrus, jasmine, lemon, bergamot, green tea, honey.

Prolong dehydration time: citrus, jasmine, maple syrup, honey, green tea, good balance and rich flavor.

[Yejashifei Red Cherry]

Do not extend the dehydration curve

It turns yellow in 5 minutes and 20 seconds, starts an explosion in 9 minutes, develops in 2 minutes and 20 seconds after an explosion, and comes out of the oven at 197.2 degrees.

Lengthening dehydration curve

It turns yellow in 5 minutes 08 seconds, explodes in 8 minutes 28 seconds, develops in 1 minute 30 seconds after an explosion, and comes out at 198 degrees.

Cup test comparison

No longer dehydration time: orange, berry, fermented fruit, nectarine, tropical fruit, sucrose, spices

Prolong dehydration time: sucrose, sweet orange, tropical fruit, fermented fruit, Chinese fir, spice

[Queen of Brazil]

Do not extend the dehydration curve

Turn yellow in 5 minutes 20 seconds, start an explosion in 8 minutes 48 seconds, develop 3 minutes after an explosion, and come out at 200.3 degrees.

Lengthening dehydration curve

It turns yellow in 5 minutes and 10 seconds, explodes in 9 minutes, develops in 3 minutes after an explosion, and comes out at 200.3 degrees.

Cup test comparison

No longer dehydration time: fermented fruits, nuts, peanuts, caramel, cocoa

Extend dehydration time: nuts, caramel, sugar cane, citrus, cocoa, rubber

[summary]

Through this experiment, we found that the overall performance of the [flower butterfly] baked with longer dehydration time was better than that baked without longer dehydration time, but the performance on [Red Cherry] and [Queen of Brazil] was slightly less satisfactory, and even showed a defective flavor.

Therefore, prolonged dehydration is not suitable for all beans, but is only recommended for beans with high water content, hard beans and difficult dehydration. However, as coffee roasting is a very complex subject, we are still groping and learning, looking forward to more results to share with you!