How does the wine process change green coffee beans?
The wine process treats green coffee beans with winemaking concepts, and so far only a few estates in Colombia have commercialized it. It splits into acetic acid fermentation, lactic acid fermentation, and mixed fermentation, each giving a different cup. Acetic acid lots tend to taste bright and clean with citric acidity, while the other styles show softer or more layered fruit character.
Cherries are sealed in a container fitted with a one-way exhaust valve, letting carbon dioxide escape while air concentration stays controlled. The washed method and the semi-washed honey method remain the most common approaches in specialty coffee, and many representative lots use them, so the wine process stays a small but distinct category of green coffee beans.
The red wine processing method is a way of processing green coffee beans that draws on winemaking concepts, and currently only a few estates in Colombia have successfully commercialized it. Depending on the fermentation environment, it can be divided into three types: acetic acid fermentation, lactic acid fermentation, and mixed fermentation, each presenting distinctly different flavor characteristics. At the same time, the washed method and semi-washed method (honey processing) remain the most mainstream processing methods in the specialty coffee field, and many of Front Street Coffee's representative beans use these processes. This article will systematically sort out the classification and flavor performance of the red wine processing method, and compare the processing flows of washed and semi-washed methods, to help coffee lovers more clearly understand the impact of processing methods on the flavor in the cup.
Flavor description and taste introduction of which coffee bean varieties at Front Street Coffee use the red wine processing method
The red wine processing method for coffee beans, also known as the red-wine-like processing method, is inspired by the winemaking process for red wine. At present, only eight estates in Colombia have successfully brought coffee beans using this processing method to market. Based on the information from these eight estates, we can roughly divide the types of red wine processing into: acetic acid fermentation (Aerobic fermentation), lactic acid fermentation (Anaerobuic anaerobic fermentation), and mixed fermentation (Mix Fermentation=Aerobic+Anaerobuic).
The selected coffee cherries are placed by farmers in a specific container (the beans used by Australian barista Sasa in competition were placed in a metal container during processing). In any case, this container should have a device similar to a red wine fermentation lock, or a one-way exhaust valve. In this way, carbon dioxide can escape through this device to control the air concentration in the container. At this time, the coffee cherries in the container undergo acetic acid fermentation. The beans produced by this reaction have a relatively bright, clean flavor with citric acidity.
The washed method is currently the most popular processing method, and most specialty coffee beans choose the washed method, such as Front Street Ethiopia Washed Yirgacheffe and Front Street Kenya Asalia. Washed coffee refining process: harvesting → water tank (remove impurities and unripe beans) → pulping machine (remove pulp and impurities) → fermentation tank (remove the mucilage attached to the parchment) → washing pool (select light and hard beans) → sun-drying yard (or dryer) → huller (remove parchment) → grading (electronic bean sorter or hand sorting, screens, etc.) → export.
The semi-washed method is also called the “honey processing method” and is a compromise between the dry method and the washed method. It omits the fermentation step of the washed method for coffee cherries and is popular in regions such as Brazil and Costa Rica. Representative coffee beans: Front Street Brazil Semi-Sun-Dried Red Bourbon, Costa Rica Musician Series coffee beans, etc. Harvesting → water tank (remove impurities and unripe beans) → pulping machine (remove pulp and impurities) → washing pool (select light and hard beans) → sun-drying yard (or dryer) → huller (remove parchment) → grading (electronic bean sorter or hand sorting, screens, etc.) → export.
The above content is compiled by CoffeeHunters, a coffee news website.
