Roastery & Lab.

1. Sample: roasted on a sample roaster and cupped before we buy.
2. Green coffee: moisture, water activity, density, screen size and defects checked.
3. Roast: on our PROBAT Probatone 12, every curve recorded.
4. Roast degree: measured with a roast analyser.
5. Taste: every roast cupped.
6. Pack: within a day of roasting, in bags with a one-way valve.
7. Rest: at least seven days in our cafés before grinding; bags leave us fresh.

Coffee passes through many hands before it reaches you: the producer, the harvest, the processing, the roast and the barista. We work with green coffee importers who have personal connections to producers, so every coffee can be traced to its farm.

New green coffees reach us as samples. We roast them on our sample roasters, an IKAWA PRO100 and a PROBAT sample roaster, and cup them before we decide which coffees to buy.

Before a coffee goes into the roaster, we check its moisture content, water activity, density, screen size and defects. Each tells us something different.

Moisture content is how much water the beans contain. Water activity shows how freely that water is available, which helps us understand how stable the beans are.

Density, screen size and defects add physical information. Density is the weight of a known volume of green beans, given in grams per litre. Measurements and cupping answer different questions, so we do both.

In the SCA’s Coffee Value Assessment, the physical assessment form records colour, moisture, size and defects, based on a 350-gram sample. Water activity is not one of its required physical tests; we measure it in addition.

In research for the SCA’s Coffee Science Foundation, trained tasters are given three cups, one containing defective beans, and asked to find it. The findings are to inform an update of the SCA’s physical assessment.

Some green coffees lose their character within a few months; others hold it for 14 or 16 months, the SCA writes. Cool, dry storage slows their ageing.

Our green coffee is stored vacuum-packed in 12-kilo GrainPro bags, inside cartons. Packaging, surroundings and time all change green coffee, so we protect it until it is roasted.

In a 2025 study in the International Journal of Food Science, one Colombian green coffee was stored for 365 days in eight kinds of packaging at four sites. The conditions at each site affected how well the packaging preserved the coffee’s quality.

We roast on a PROBAT Probatone 12, gently, to bring out the subtle nuances of each coffee. Roasting software records the temperature curve of every batch, so we can see how it developed and compare it with the profile we chose for that coffee.

A Lighttells roast analyser measures the roast degree of each batch, so we can compare one batch with the next. Roast degree alone does not decide taste: two roasts of a similar degree can taste different. That is why we taste every roast as well.

We taste and test every roast. For formal assessments we use the SCA’s Coffee Value Assessment. To compare green coffees fairly, its standard prepares each sample the same way: a medium sample roast, rested for 8 to 24 hours. Feedback from both our cafés is recorded regularly and comes back to the roastery.

The SCA’s Coffee Value Assessment looks at a coffee in four separate ways.

• The physical assessment looks at the green beans themselves.
• The descriptive assessment records what a taster perceives, such as aroma, flavour and acidity, without judging it.
• The affective assessment records how the taster judges its quality.
• The extrinsic assessment collects what cannot be tasted, such as origin, variety or processing.

Keeping them apart means a description is not a verdict.

An Atago refractometer measures the strength of a brew: its total dissolved solids, or TDS. With the weight of the dry coffee and of the finished drink, this reading lets us calculate how much of the coffee was extracted. Strength and extraction answer different questions: how concentrated the drink is, and how much of the coffee ended up in it. We use both alongside tasting to check our espresso and filter recipes.

Water is an ingredient. Its minerals, and especially its buffering capacity, change how acidity and other flavours come across. We treat the water we use for brewing and cupping. For cupping, the SCA’s standard sets ranges for hardness, alkalinity and pH, and asks for water without chlorine.

We pack each coffee within a day of roasting, in bags with a one-way valve, and send it out as fresh as possible. It rests on its way to you and once it arrives. In our cafés, every coffee rests for at least seven days after roasting before it is ground.

After roasting, beans keep releasing gas for some time; the valve lets it out while limiting the air that gets in. Once opened, close the bag, keep it cool and dry, and grind just before brewing.

Masih Mansouri, our manager and roaster, is a Licensed Q Instructor and Authorized SCA Trainer. He holds the SCA Roastery Skills Diploma.

We teach SCA Coffee Skills Program courses in Barista Skills, Brewing, Sensory Skills and Green Coffee, and the SCA’s Q Grader Program.

Our roastery café is at Boxhagener Straße 82.

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