Anaerobic fermentation has become very popular in the coffee industry in recent years. This trend was mainly caused by the Australian contestant Sasa Sestic who won the WBC championship in 2015. Even among the top six contestants in the 2018 WBC competition, five of them used "anaerobic fermentation" coffee beans to compete. You can know what is special about it!
During the processing of green coffee beans, "fermentation" will be encountered to a greater or lesser extent, and it will profoundly affect the flavor of the coffee beans. Fermentation is generally divided into two types: "aerobic" and "anaerobic". The biggest difference between the two is that the anaerobic process is more uniform and can be controlled, but there are too many environmental variables under aerobic conditions and it is not easy to monitor. Generally speaking, most traditional treatment methods are "aerobic" fermentation, and only in recent years have anaerobic fermentation treatments been slowly developed.
Anaerobic fermentation treatment, also called carbonic maceration, is inspired by the red wine production process, so it is also called red wine treatment. "The grapes will be put into carbon dioxide gas to bring the grapes into an anaerobic state. In this way, even if there are no yeasts, the grapes can convert their own fructose into alcohol, so they have a special aroma, and the brewed wine will have a soft aroma and a rich taste." Back to the processing of green coffee beans, freshly picked coffee cherries are put into a sealed metal can, and carbon dioxide is injected into it to promote the discharge of oxygen, create an anaerobic fermentation environment, and reduce the decomposition rate and pH of sugar in the coffee bean pectin. value decreases, allowing the beans to obtain higher sweetness and a more distinctive flavor.
The coffee beans that Sasa Sestic used in the 2015 WBC were Rume Sudan from Las Nubes, Colombia. According to him, the anaerobic fermentation method used in this coffee bean mainly involves placing mature coffee fruits in a sealed metal container (stainless steel barrel), injecting carbon dioxide, and expelling oxygen, so that fermentation and decomposition can be carried out in an anaerobic environment. The pH value, gas composition, humidity, temperature, and even the type and number of bacteria involved in the fermentation process can be effectively controlled to develop better sweetness and a more balanced flavor.
However, at present, various processing plants and various types of green bean processing known as anaerobic fermentation are actually different. After all, this type of processing method is still in the development stage, so there is no standard or absolute version. Most of what we have heard so far is based on Sasa's coffee bean processing method at that time, or modified from this version. For example, recent experimental processing methods such as anaerobic sun drying, anaerobic washing, and double anaerobics have appeared one after another, which is also very exciting. Adding the anaerobic process to the solarization or washing treatment method has become our common anaerobic solarization and anaerobic washing treatment methods.
adoptAnaerobic solarizationWill just pickThe coffee cherries are placed in sealed barrels for low-temperature fermentation. In an anaerobic environment, the decomposition rate of pectin decreases, and the pH value decreases at a slower rate, prolonging the fermentation time of coffee, thereby developing more sweetness. The temperature must be strictly controlled in the entire anaerobic environment, with an average of 10 to 15 degrees Celsius. After more than three days of anaerobic fermentation, the coffee cherries in the barrel are sun-dried. Finally, the excess parts of the dried coffee cherries are removed and the coffee beans are taken out.
For example, the Front Street Colombian Flower Moonlight Coffee Bean on the Front Street Bean List is subjected to anaerobic sun treatment. This Front Street Columbia Flower Moonlight Coffee Bean obtains a richer, sweet and sour ripe fruit and fermented aroma due to anaerobic sun exposure. After baking, it shows the aroma of cranberry, strawberry jam, liqueur chocolate, cream, and rich fermentation flavor.
The anaerobic washing treatment method involves dry fermentation of freshly picked coffee fruits for 12 hours, and then the peel and pulp are removed by machine, and then the coffee beans are placed in a sealed fermentation barrel for anaerobic fermentation for 24 to 48 hours. After the fermentation is completed, the coffee beans in the barrel are dried. The coffee beans processed in this way present a very rich and fruity sweet taste. Front Street Columbia Rose Valley coffee beans are processed using anaerobic washing methods. You can feel the aroma of peach and rose when brewing by hand.
The so-called double anaerobic washing is divided into two anaerobic steps. The coffee cherries are processed immediately after being picked, and the coffee cherries are placed in a sealed anaerobic environment for the first anaerobic fermentation. After fermentation, the coffee cherries are removed and the peel and pulp are removed according to the water washing method. The coffee beans with pectin are again placed in a sealed anaerobic environment for the second anaerobic fermentation. Finally, the fermented coffee beans are dried in the sun and the moisture content is reduced to 11% to complete the process.
The characteristic of two anaerobic fermentations is called double anaerobic washing. Front Street Columbia Paradise Estate Sakura coffee beans are double anaerobic washed. Due to the processing method, they present flavors such as spiced tea, citrus, dark cocoa, and mint.
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You can now buy the above coffee beans online at the Taobao store “FrontStreet Coffee” (前街咖啡). FrontStreet Coffee is a long-established specialty coffee roaster in Guangzhou, China, and its Guangzhou retail shop sells coffee beans only. The shop carries dozens of coffee beans from different origins around the world, including carefully selected single-origin beans for V60 pour-over and espresso. Guangzhou’s FrontStreet Coffee shop is recommended by many coffee lovers.
The FrontStreet 2013 Yunnan coffee beans sold in the store come from the Typica variety grown at FrontStreet Coffee’s own plantation in Yunnan. The name comes from the year the brand and the plantation were founded. You can buy these beans from China’s Yunnan origin at the Guangzhou shop and at FrontStreet’s Taobao store.
FrontStreet coffee beans are freshly roasted within 5 days and deliver consistently excellent quality and great value. Orders placed before 17:00 are shipped the same day, and most areas within Guangdong Province receive them the next day.
FrontStreet Coffee Taobao store: https://qianjiecoffee.taobao.com
Or search for “前街咖啡” (FrontStreet Coffee) on Taobao
Important Notice: FrontStreet Coffee has moved to a new address: 315, Donghua East Road, Guangzhou (coffee beans only)
Tel: 020 38364473
