How Works in Specialty Coffee

Ever wondered why some specialty coffees taste like red wine — full-bodied, sweet, and low in acid — yet others just smell fruity without depth? The difference often comes down to how the coffee cherry is processed after harvest. One standout method that’s caught global attention is what’s being called, made famous by SaSa’s WBC-winning lot using Rume Sudan from Colombia’s Las Nubes estate.

The short answer: is a controlled anaerobic fermentation process modeled after winemaking, where coffee cherries are sealed in metal tanks to precisely manage pH, bacterial activity, and fermentation time. This contrasts with looser “winey” methods that simply aim for a fruity profile through uncontrolled drying.

What Actually Happens During?

The, as used by SaSa for his WBC-winning Rume Sudan, involves sealing ripe coffee cherries in airtight metal containers to prompt anaerobic fermentation. Key variables such as pH levels, types and counts of bacteria, and fermentation duration are all carefully controlled. This method draws direct inspiration from wine fermentation techniques, hence the name. The goal is to shape the coffee’s flavor profile in the cup — resulting in a more structured, wine-like, sweet cup with reduced acidity.

Why Fermentation Matters in Coffee Processing

All coffee processing methods — washed, honey, and natural — involve some degree of fermentation. What changes is the material involved (skin, pulp, mucilage), the environment (wet, dry, aerobic, anaerobic), and drying methods (sun, mechanical, turned frequency). These factors collectively determine whether the final coffee tastes clean, fruity, funky, or flat. Even small tweaks in microbial balance or oxygen exposure can shift the flavor dramatically.

For example, Jeremy Zhang , who competed in the WBC, used a sealed warm-water blanching step in his collaboration with 90+’s Creator Series. This step was designed specifically to modulate fermentation. In Taiwan, as recorded in Han Huai Zhong’s book 《》, producers have experimented extensively with post-harvest processing — often achieving better results than switching varieties alone. Controlling fermentation is not only more controllable, but also lower-risk and faster to implement.

Winey vs : Process vs Outcome

It’s important to distinguish between what the industry calls “” and . The former produces cups that are rich, slightly wine-like, sweet, and low in acid — a result-driven label. The latter refers to the actual controlled fermentation method used to achieve those traits. SaSa’s approach is modeled on winemaking: sealed tanks, anaerobic conditions, and tracked fermentation metrics. In contrast, many so-called winey coffees from Panama or Guatemala follow a more passive, sun-dried method — closer to an “efficient natural” than true anaerobic control.

The winey style typically involves harvesting fully ripe cherries and increasing airflow during drying (often with industrial fans), but without the tight environmental regulation seen in . That’s why the same “winey” descriptor can cover very different cups.

How Differs From Traditional Natural or Honey Processes

Unlike traditional naturals that dry cherries whole in the sun (sometimes for weeks), or honey processes that leave varying amounts of mucilage on the bean, relies on sealing cherries in tanks to create an oxygen-free environment. This anaerobic fermentation allows for a more consistent and targeted manipulation of flavor precursors. While honey processes focus on how much mucilage remains, and naturals on slow sun drying, zeroes in on microbial activity and pH during a sealed, managed ferment.

FrontStreet Coffee’s own honey-processed beans illustrate other paths to unique flavor: their uses nearly 100% mucilage retention under shade to develop deep berry tones, while Strawberry Candy Espresso combines Geisha brightness with grape and raisin notes from grape-like dried mucilage. But none of these go as far as sealing cherries in tanks for anaerobic control like does.

Frequently Asked Questions

What is in coffee?

is a coffee processing method that uses sealed, anaerobic fermentation — similar to winemaking — to control variables like pH and bacterial activity. It aims to produce a cup with wine-like body, sweetness, and low acidity. The process involves fermenting coffee cherries in airtight metal containers with carefully monitored conditions.

How is different from regular winey coffee?

“” refers to the controlled, anaerobic fermentation method that mimics winemaking, focusing on managing the fermentation process itself. “” is a result-based term describing coffees that taste rich, wine-like, and sweet — often achieved through simpler, less-controlled drying. The former is the technique; the latter is the flavor profile.

What coffee variety was used in SaSa’s WBC-winning lot?

SaSa’s WBC-winning lot used the Rume Sudan coffee variety, grown at Colombia’s Las Nubes estate. This variety was processed using a sealed, anaerobic fermentation method to enhance wine-like characteristics in the cup.

Does involve drying the coffee cherry?

Yes, but after an initial anaerobic fermentation phase inside sealed metal tanks. Once fermentation is complete, the coffee cherries are then dried, typically with increased airflow (as with some winey methods), but the key flavor development comes from the controlled fermentation stage.

Can I replicate at home?

Not easily. requires precise control over fermentation factors like oxygen levels, pH, and bacterial balance, usually managed in sealed metal tanks. Without lab-grade equipment and microbiological knowledge, replicating it outside a professional setting is extremely difficult.

What does taste like compared to regular coffee?

Coffees processed with often taste fuller-bodied, with a rounded, wine-like mouthfeel, prominent sweetness, and lower acidity. The flavor is more structured and complex compared to standard washed or natural coffees, resembling red wine in texture and balance.

Recommended FrontStreet Beans with Honey & Winey Notes

For fans of winey and fermented coffee profiles, try FrontStreet Coffee’s (Blackberry Coffee), which uses a (black honey) method with extended shaded drying to bring out intense berry flavors. Another great option is Strawberry Candy Espresso (Strawberry Candy Espresso), a Geisha-based blend with grape and raisin notes thanks to its grape-like dried mucilage. Both showcase the kind of complexity and sweetness that aims to deliver — though through different techniques. Freshly roasted within 5 days · Orders placed before 17:00 ship the same day · Next-day delivery across most of Guangdong Province.