Understanding Fermented Coffee: What It Is and How to Make It ( In 3 To 5 Days )

Vietnamese Coffee Exporter
Understanding Fermented Coffee

Understanding Fermented Coffee: Coffee enthusiasts are always innovating, finding novel ways to brew and enjoy their beloved beverage. One of the more unconventional varieties you may have encountered is fermented coffee.

But what exactly is fermented coffee? It can refer to either the beans or the brewed drink. For beans, the fermentation process occurs during the post-harvest stage, where natural microorganisms break down the sugars, enhancing the flavor profile. As for brewed coffee, fermentation involves letting the coffee sit with specific cultures to develop unique tastes. It’s simpler than it seems, and we can guide you through the process of making it at home. Experience the rich, complex flavors that fermented coffee brings to your cup.

Understanding Fermented Coffee Beans

You might be wondering – are coffee beans fermented? Indeed, they are. Wet-processed beans naturally ferment while soaking.

However, when we mention fermented beans, we mean beans that have undergone a deliberate and controlled fermentation process after drying – specifically, as green coffee beans.

Once these beans have been fermented, they are roasted in the usual manner, ready for brewing. You’ll find them marketed as either fermented or cultured coffee beans.

Exploring the Coffee Fermentation Process

Fermenting coffee beans involves a natural chemical reaction similar to those that create cheese and wine. The key to achieving a delicious result instead of a rancid one is careful control of the process.

The main method begins with green beans that have been processed—either washed or naturally. These beans are soaked in water, inoculated with specific bacteria, and left to sit for 1-2 days. Once fermentation is complete, the beans are washed and dried, preparing them for roasting.

Alternative methods include barrel aging or adding ingredients like fruit to the fermentation tank, each imparting unique flavors to the coffee.

The Benefits and Reasons Behind Coffee Fermentation

Fermented coffee may appear to be a trend, but the fermentation process actually brings significant and positive changes to the beans. Beyond the usual health benefits of coffee, fermentation makes the drink easier to digest, reduces the presence of harmful bacteria, and lowers tannin levels. Additionally, it enhances the flavor profile of the coffee, imbuing the beans with more complex tasting notes.

Fermentation helps the beans absorb different flavors, resulting in a richer and more nuanced cup. While coffee fermentation adds unique characteristics to the taste, the final flavor will still depend on the original beans and the brewing method used. This process offers a fascinating way to explore new dimensions of coffee enjoyment.

Fermented Brewed Coffee: A Unique and Probiotic Beverage

Fermented coffee can also refer to a coffee drink where brewed coffee undergoes a fermentation process. This method creates a unique beverage with a tangy flavor and slight carbonation. Additionally, it’s packed with probiotics that support gut health and improve digestion.

Making fermented brewed coffee follows the same basic principles as other fermentation processes. You’ll need the right bacteria and a sugar source for them to consume, then allow nature to take its course. Common methods for introducing the necessary bacteria include using kefir, kombucha, or beer yeast, each contributing to the drink’s distinctive taste and health benefits.

Experimenting with different bacteria sources and fermentation times can yield a variety of flavors, making each batch of fermented coffee a unique experience. This innovative approach offers a new way to enjoy coffee while reaping the benefits of probiotics.

DIY Fermented Coffee: A Step-by-Step Guide

The simplest way to ferment coffee at home is by using the kombucha method. If you haven’t made coffee kombucha before, the most crucial step is obtaining or creating a kombucha SCOBY. This symbiotic culture of bacteria and yeast initiates the fermentation process.

Ingredients for Fermented Coffee Drink:

  • 2 quarts of brewed coffee
  • 1/2 cup of sugar
  • Kombucha SCOBY

At a Glance:

  • Brew Time: 3-5 days
  • Container: Glass jar


  1. Combine the sugar and brewed coffee in a glass jar, stirring until the sugar dissolves. Allow the mixture to cool.
  2. Add the SCOBY and cover the jar with a cheesecloth or coffee filter, securing it with a rubber band.
  3. Let the mixture ferment at room temperature for 3-5 days, away from direct sunlight. Check daily for any signs of spoilage.
  4. Once the desired taste is achieved, remove the SCOBY and store the fermented coffee in the refrigerator.

This homemade fermented coffee offers a unique and refreshing way to enjoy your favorite beverage, complete with probiotic benefits and a distinctive flavor. Experiment with fermentation times to find your perfect brew!