The Complete Guide to Natural Process Coffees: Natural, Anaerobic, and Low‑Oxygen

When you sip a cup of coffee bursting with sweet berry flavors, wine‑like complexity, and a syrupy body, there’s a good chance it’s a natural process coffee. Known for its fruit‑forward profile, the natural process is one of the oldest — and most flavor‑packed — coffee processing methods in the world.

But not all naturals are the same. In recent years, specialty coffee producers have experimented with anaerobic fermentation and low‑oxygen techniques — like Rwanda’s clay-pot process — to unlock even more distinctive flavors.

In this guide, we’ll explore what makes each of these natural coffee processing methods unique.

1. Natural Process Coffee

The natural coffee process (also called dry process coffee) is the original way coffee was prepared for export. Freshly harvested coffee cherries are laid out to dry whole — fruit, skin, and all — usually on raised beds or patios.

As the cherries dry, sugars and flavors from the fruit infuse into the bean, producing an intensely sweet and fruity cup.

• Flavor profile: Blueberry, strawberry, tropical fruit, wine‑like acidity, heavier body.

• Common origins: There are Naturally Processed Coffees everywhere these days!

• Best for: Coffee drinkers who love bold, jammy flavors and a rich, sweet cup.

Because the coffee dries inside its fruit, the drying stage must be carefully monitored to avoid over‑fermentation or mold.

2. Anaerobic Natural Process Coffee

Anaerobic natural coffee is a modern twist on the traditional natural process. Instead of simply drying the cherries in open air, producers ferment the whole cherries in sealed tanks without oxygen for a specific amount of time before drying.

The absence of oxygen changes how microbes break down sugars, often leading to more intense and specific aromatic flavors than standard naturals.

• Flavor profile: Punchy tropical fruit, floral aromatics, sparkling acidity, complex fermentation notes.

• Common origins: Colombia, Guatemala, Bolivia, Rwanda, Ethiopia

• Best for: Adventurous coffee lovers who enjoy expressive, layered flavors.

Keyword connection: People often search for "anaerobic natural coffee flavor" and "what is anaerobic coffee processing" — this section answers both.

3. Low‑Oxygen Natural Process Coffee

Low‑oxygen natural coffees are a newer category. Instead of complete oxygen removal (as in anaerobic fermentation), coffee cherries are fermented in low‑oxygen environments — often with partial submersion, semi‑sealed containers, or sealed chambers made of porous materials.

One fascinating example is Rwandan Producer Baho Coffee's Intango process. In this method, whole cherries are placed in clay pots and allowed to ferment naturally with minimal oxygen exposure before being dried. This creates layered complexity without overpowering fermentation flavors.

• Flavor profile: Balanced fruit sweetness, soft florals, refined acidity, elegant complexity.

• Common origins: Rwanda, some experimental lots from Ethiopia and Central America.

• Best for: Drinkers who want the vibrancy of naturals with a smoother, more refined edge.

Why These Methods Matter

The difference between classic naturals, anaerobic naturals, and low‑oxygen naturals lies in fermentation control. Fermentation shapes flavor, aroma, and mouthfeel — making it a powerful tool for coffee producers.

• Classic Naturals → Sweet, bold, fruit‑forward.

• Anaerobic Naturals → Intensely aromatic, adventurous, and complex.

• Low‑Oxygen Naturals → Elegant, nuanced, and refined.

Understanding these methods helps you choose coffees that match your flavor preferences — whether you’re after wild, fruit‑bomb naturals or subtle, sophisticated low‑oxygen lots.

Finding Your Perfect Natural Coffee

Next time you’re browsing the Bellwood shop, look for processing details on the bag. We'll usually highlight if a coffee is anaerobic or low‑oxygen, because these methods have become flavor-defining features.

If you’re curious, try a tasting flight of the three side‑by‑side. You’ll taste firsthand how the processing method transforms the same coffee cherry into dramatically different cups.