Reigen Fermentation

Reigen is a Berlin-based sake brewery located in the basement of a former bowling alley. The old Keglerklause was renovated in 2022 together with our neighbors aru, Ernst Cave, and Julius. Since 2024, it has been home to Reigen: an open manufactory for high-quality European sake and other koji-based beverages.

At the heart of our work is sake made using the traditional Bodai-Moto method. This ancient fermentation technique brings out complex, layered flavors: bolder, more expressive, and sometimes funkier than conventional sake.

Alongside sake, our range includes sweet and savory non-alcoholic amazake and sake-kasu, the aromatic lees left after pressing.

Handcrafted in small batches, our products are made for sake connoisseurs, wine lovers, and anyone curious about new flavors, whether in the glass or in the kitchen.

Good fermentation starts with good ingredients and attention to detail.

Our rice comes from De Tacchi, a family-run farm in Northern Italy. Instead of highly polished sake rice from Japan, we use Italian risotto rice with a low polishing rate. This adds depth while reducing transport emissions.

Our koji is made in-house. It forms the base for both our sake and non-alcoholic drinks. In sake production, it enables the conversion of starch into sugar, making alcoholic fermentation possible. At the same time, it brings structure, complexity, and character.

And our water: filtered Berlin tap water, clean, mineral-rich and tied to the place where everything is made.

Fermentation is where the sake comes to life. But what happens before, during, and after is just as important: each step shapes flavor, structure, and balance.

1. We start by washing the rice to remove excess starch, then steam it as the base for both koji cultivation and brewing.

2. Warm rice is inoculated with Aspergillus oryzae. Over two to three days, it develops aromas and the enzymes needed to convert starch into sugar: the foundation of fermentation.

3. The ingredients are brought together and fermentation begins. Sugar turns into alcohol, while flavor, structure, and complexity build layer by layer.

4. Once fermentation is complete, the mash, traditionally called "moromi", is gently pressed in our custom-made, traditional-style fune press.

5. For our sparkling varieties, we bottle the sake while fermentation is still clearly active. This allows the carbon dioxide to develop naturally through a second fermentation in the bottle, similar to Pet Nat. Depending on the style, we disgorge selected batches before topping up and sealing the bottles.

6. The sake then matures at room temperature. Some batches develop gently through light oxidation in tank, while others are bottled fresh. All remain "nama", unpasteurized, for maximum flavor. We never use preservatives.