The principle of Coffee Bean anaerobic fermentation Coffee by anaerobic fermentation

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What is fermentation?

Let's go back to our high school science class: fermentation is a chemical reaction. The combination of yeast, bacteria, and other microorganisms breaks down one substance into other simpler substances. Usually, the decomposing substance is sugar. When this happens, they release heat. Moreover, different kinds of enzymes can catalyze this event.

Or, more simply, fermentation is a natural change that happens when you put sugar and water together-and coffee fruits are rich in both. Therefore, after the cherries are picked (or sometimes before, depending on the humidity), the fermentation process will begin.

The problem is that fermentation can improve the taste of coffee or destroy it. It's just a matter of how you handle it.

What does fermentation have to do with coffee?

Fermentation is the key link of post-harvest coffee processing. It can happen in two ways:

Aerobic: this happens when there is oxygen. The fermentation project is simple: put the freshly picked cherries in a container and let the microbes work. Monitor time and temperature to help you control and analyze it.

Anaerobic: in this case, the coffee cherry is placed in a trough (before or after pulping) and covered in water. This allows different microbes to work.

So, what's the difference? Well, Carlos told me, "the anaerobic process is more uniform and easier to monitor, while aerobic exercise is more uneven and more complex to monitor."

But you don't have to choose one of them. Carlos explained that at O & # 39 position Coffee, they performed both aerobic and anaerobic treatments, and sometimes they even "started with aerobic treatment and ended with anaerobic treatment".

There are many methods of fermentation, and the more experiments we do, the more we know about the quality of coffee.

How does fermentation affect the quality of coffee?

Because fermentation is so complex, there are many different potential results. Bad, uncontrolled fermentation can cause coffee to mildew and even produce a chemical flavor-which is why it is so important for producers to understand the process, monitor it, and work according to best practices.

Because when the fermentation is successful, it can improve the best quality of coffee.

Carlos told me that the fermentation experiment of O & # 39 Tech Coffee is to "expand their product range and provide their customers with unique coffee, exotic coffee." It basically refines the sweetness, acidity and taste of these coffees, adding unique sensory flavors such as fruit, caramel and chocolate. "

As Dr Britta Folmer Volmer wrote in his book Coffee Technology and Science (The Craft And Science of Coffee), "it is said that the purpose of removing mucus by underwater fermentation is to emphasize the acidity and aroma of coffee and to eliminate some astringency." Natural pulping coffee or honey processing coffee is a combination of wet and dry processes. In the drying stage, the mucus cannot or can only be partially removed, which may lead to a certain degree of limited fermentation. This can produce some special sweetness, closer to the natural process. "

But manufacturers must be careful. As Carlos told me, "fermentation for too long may lead to a significant decline in sensory quality." The acidity, body and sweetness of the wine will decline significantly. "

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