Roasting Intermediate in Kathmandu, Day 1: Understanding the Machine

The first day of SCA Roasting Skills Intermediate in Kathmandu began with the roaster itself. Before comparing flavour, students measured drum rotation and explored how drum speed, airflow and energy affected the machine’s behaviour. Changing airflow settings gave the group a practical way to discuss where heat was generated, how air moved through the drum and how much energy was being removed.

From there, the class built a reference map between first and second crack. Students worked through light, medium-light, medium-dark and dark profiles, then compared faster and slower approaches. Adjusting batch size helped them explore how the same energy input could produce different responses. By the end of the day, more than eight training batches were ready for cupping.

The purpose was to connect control at the machine with decisions that could later be tested in the cup. Working across several roast levels gave students a broader set of comparisons than a single target colour could offer. Each batch became material for the next day’s sensory evaluation.

We closed with discussion of roast defects, including tipping, scorching, facing and cratering. Thank you to Nepal Coffee Producers Association and HAMRO COFFEE for supporting this practical roasting training in Kathmandu.