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What Is Anaerobic Processing?

Mar 22, 2021 · coffee · culture · educational · processing
What Is Anaerobic Processing?

There’s a type of processing currently on the rise that could create a large shakeup in the coffee world: Anaerobic fermentation! We’ve got the lowdown on this interesting innovation in coffee processing, so let’s get started!

What is Anaerobic Processing?

We know that natural processing leaves the cherry on the bean, producing stronger flavors, and washed processing removes the cherry before drying. Anaerobic fermentation is quite a bit different than both of these processes. In Anaerobic processing, coffee cherries are placed in tanks that are airtight and pressurized to prevent CO2 buildup. Oxygen is then drained from the tanks using valves to create an interior devoid of it. Sometimes this process occurs with the mucilage on or partially removed, as with a natural or honey processed bean, or with the mucilage completely removed via washing. In any event, this oxygen devoid environment encouraged the development of acids like lactic acids. These acids can produce unique flavors in the coffee that tend toward a fruity complexity. The flavor of the bean can be further influenced by that removal of the mucilage before placing in the tanks. This processing method does require specialized equipment, but it isn’t that difficult to assemble for many producers already operating processing facilities. The proof of the staying power of this type of coffee processing is already in the pudding - Anaerobic coffees have had strong showings at the United States Barista Championships and the World Barista Championship in recent years.

What’s in it for Producers?

Aside from the benefits that this method of processing has for the flavor of coffee, there’s another reason that farmers have an interest. Typically, elevation plays into the perceived quality of a coffee. Coffees grown at higher elevations develop more complex flavors, as the cooler temps slow down development of the cherry. This leads to significantly more sought after flavors in the cup than with lower grown coffees. This in turn creates higher pricing opportunities for farms operating at higher elevations. The issues with growing at high elevations aren’t hard to imagine, though. For starters, building the infrastructure to grow coffee high in the mountains is no easy task. On top of this, transporting coffee to processing plants from these high farms is a challenge, often requiring significant logistical effort. Then there’s the fact that there simply aren’t as many high elevation farming locations as there are lower laying ones. Because of this, oftentimes coffees grown at lower elevations go for a lower price, and it’s hard to break away from that. Anaerobic processing imparts some of the complexity that coffee drinkers prefer high elevation coffee for. This method of processing has the potential to increase prices for farmers at lower elevation farms. The result is a greater quantity of tasty coffee, and more even pricing for farms at lower elevations. The hope is that this creates a more equitable pricing model for farms operating at these lower elevations. How anaerobic processing develops remains to be seen, but it’s certainly set to shake up specialty coffee in a big way.

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