Commercial coffee roasters: sizing, buying, installing and running drum roasters from 1 kg to 300 kg.
Robusta behaves differently from arabica in a drum roaster — a rigid cell structure, a quiet first crack, a longer and hotter roast — and it changes the production line too: separate profiles, more smoke, a lower batch size by volume. What to test first and how to run both on one machine.
When a roaster’s bean probe reads wrong, the cause is usually wiring or settings, then fouling or position, and only last the sensor itself. How to check each in order, calibrate with ice and boiling water, and what to do when you finally replace a thermocouple.
A symptom-by-symptom troubleshooting guide for drum coffee roasters: the checks an operator can do in five minutes for a burner that won’t light, a flame that drops out, a drum that stops or a probe that reads wrong — and the signs that mean stop and get support.
Drum bearings are the wear item on every coffee roaster. How to grease them, the three signals — sound, hand, motor current — that say replace, the replacement sequence for light and heavy drums, and how to buy the part locally instead of waiting for a shipment.
Decaf behaves differently in the drum — darker green, weaker first crack, faster after it, lower weight loss. What changes in the profile, why the probe matters more than the eye, and the four production consequences of adding a decaf SKU.
Roasting is rarely the bottleneck; packing is. Staffing bands from under 100 kg to over 2,000 kg a week, where the hours actually go, and which equipment removes a person from the line.
Delivery day, step by step: what to have ready, how to inspect the crate before signing, where to uncrate, how to move 200–800 kg through a door and onto its footings, and what not to connect yet.
The gas, thermal and operator protections a commercial roaster should carry, what each one does, how to see it demonstrated in the pre-shipment test, and what happens without it.
A framework for coffee brands: what a contract roaster charges you for, what owning a machine costs beyond the machine, the volume where the lines cross, and the non-financial reasons that override it.
Contract roasting is a changeover business, not a volume business. The equipment that makes switching clients fast and safe — profile storage, destoning, packaging, sampling — and how to size it.
