What is fermented coffee?Published Date:
It’s safe to say that coffee growers, lovers, brewers, roasters, and enthusiasts are an experimental bunch! Innovations in coffee preparation and coffee culture come thick and fast with more variety every year.
This includes innovation in the way that coffee is harvested, dried, and roasted. There has never been more variety in the coffee market and coffee growers and roasters are branching out into new and different approaches.
One of these new approaches to coffee production that has the community abuzz is anaerobically fermented coffee. Here is one of our favorite examples, Fazenda Joia Rara fermented Brazilian coffee to start your fermented coffee drink adventure right now!
Read on to learn all about delicious fermented coffee drinks and what this invigorating new process means for your coffee drinking experience!
What is fermentation?
Fermentation is a metabolic process carried out by bacteria and fungi. Organic molecules, specifically amino acids, sugars, and proteins, are metabolized in the absence of oxygen (anaerobically) by specialized bacterial and fungal lifeforms.
The product varies depending on what is being fermented and which organism is doing the fermenting but the process is vital in the production of bread and alcoholic drinks such as beer and wine.
Types of Fermentation
There are several types of fermentation used in the production of food, only some of which are relevant to anaerobic coffee fermentation and naturally fermented coffee.
Lactic acid fermentation is common in many foodstuffs, including coffee. It is defined as the fermentation of organic sugars to lactic acid in lactate form.
Ethanol fermentation is the basis for cultural alcohol traditions that date back millennia. The production of ethanol from fruit or grain sugars and starches is as old as human civilization.
Acetic acid fermentation is critical in the production of fermented condiments such as vinegar and has been relevant for millennia, being part of the production of the world-renowned Roman garum and many other foodstuffs besides.
What is fermented coffee?
Fermentation is a natural part of the coffee production process. Natural coffees (those that are prepared and dried in their coffee cherries) experience fermentation as bacteria break down the coffee fruit sugars into acids, alcohol, and other substances.
Washed coffees (where the coffee bean is removed from the coffee cherry to be dried) also ferment as they are extracted through a pulping process that keeps them in exposure to the cherry sugars and bacterial agents. They are then allowed to ferment for a time prior to washing.
Fermented coffee drinks are made with fermented coffee grounds of anaerobic coffee beans - coffee fermented with yeast. This means that the beans, or cherries of a natural process coffee, are sealed in an anaerobic environment (one without oxygen). They are then allowed to ferment for a period from a few hours to several days.
How is Coffee Fermented - Step-by-step process
First, the cherries are harvested and sorted. High-quality cherries go through one of two processes after being selected in the sorting.
Natural process coffee cherries are immediately sealed in an anaerobic environment. Usually, a barrel or tank with a one-way gas valve, to ferment.
Washed coffee cherries are pulped and the coffee beans are extracted. The extracted coffee beans are then sealed in an anaerobic environment to ferment. After a fermentation process of a few hours to several days, the coffee beans are dried, with several methods being employed from sun-drying to pre-roasting in ovens.
After the beans are dried, fermented, and matured, they are expertly roasted. This complicated and precise procedure gives coffee much of its character. It is the job of the roaster to bring out the best characteristics of the coffee they are presented with - no easy task when dealing with the detailed, nuanced, and rich palette offered by anaerobic coffee beans and the fermented coffee drinks that they produce!
After roasting the beans are packaged and exported for sale to the happy coffee drinker!
How does fermentation affect the quality of Coffee? What does fermented coffee taste like?
Fermented coffees vary widely and wildly in flavor profiles and intensities, as do all the world’s finest coffees. What is common between fermented coffee drinks is that they are of creamier texture and express a reduction in bitterness relative to unfermented coffee. Sweeter, fruitier flavors are brought out of fermented coffee grounds in extraction.
Good coffee brewing processes will produce the kind of anaerobic coffee drink that third-wave connoisseurs celebrate for ‘not tasting like coffee’, by which they mean that fermented coffee drinks have rich and complex profiles that foreground the subtler coffee flavors, such as fruit, chocolate, caramel, citrus, and especially pineapples and cherries.
Fermented coffee drinks are usually produced using the pour-over method or similar, as this extraction profile flavors the fruity, sweet aromatic compounds in the fermented coffee grounds.
Benefits of Fermented Coffee
Fermented coffee is thought to be easier to digest, in that the compounds that give coffee its character are often present in a more readily bioavailable form in fermented coffees. This makes it easier on people with IBS and other digestive conditions!
Fermented coffees last for longer without spoiling than unfermented coffees and have fewer tannins, making fermented coffee a superior choice if you are worried about staining your teeth!
Frequently Asked Questions
Is fermented coffee good for you?
Fermented coffee is more easily digestible than unfermented coffee and it causes less straining of the teeth. It may be preferable to those with a digestive disorder or a delicate stomach.
Can you make fermented coffee at home?
While you cannot ferment the beans prior to roasting unless you intend to also roast them yourself, it is possible to make a fermented drink from brewed coffee! ½ cup of sugar with 8 cups of brewed coffee in a mason jar, mixed with yeast or with kombucha SCOBY (or similar live-culture fermentation starter), covered with cheesecloth, and left for 3 to 10 days will produce a fermented coffee-kombucha drink that is said to be a health booster!
How long should coffee be fermented? How long does it take for coffee to ferment?
As the fermentation process of coffee is, like the other processes involved in producing coffee, about placement on the spectrum of flavor intensity for each of the many hundreds of flavors that define coffee. This means that different lengths of fermentation can have very different impacts on the flavors of the final product. Resultantly, the length of time that it is appropriate to ferment coffee depends entirely on the intended outcome and ranges from a few hours to a couple of weeks.
Does the Brewed Fermented Coffee Go Bad?
Eventually, the organic molecules of fermented coffee drinks will begin to decay to bacterial and fungal action, much like the bacterial and fungal action that formed the fermented drinks in the first place. However, both fermented coffee beans and fermented coffee drinks will last longer than unfermented coffee due to the decay-delaying effects of the fermentation processes.
Is fermented coffee alcoholic?
Alcohol, specifically ethanol, is the product of fermentation processes that make use of yeast. It is possible for fermented coffees to contain small amounts of alcohol, though most do not as the fermentation is a controlled process making use of specific and select microorganisms.