For the World Brewers Championship in Boston earlier this year I roasted my competition coffee using an Ikawa Roaster, a great little roaster that worked out very well.
For future competitions, I am back exploring "Competition Roasting" on our 15Kg Loring Falcon Smart Roast. I recently attended a "Loring Certification Workshop" hosted by Rob Hoos and Michael de Renouard at the Loring Showroom in Copenhagen.
That workshop gave me some new insights and ideas regarding roasting smaller batch sizes on the machine, something I haven't done before (at April and Sustainable Profile we are roasting 12kg batches exclusively).
There are a few things that are important to consider when it comes to roasting smaller batch sizes, in this case, 20% capacity or 3kg.
1. Your Thermocouple probes will read temperature differently since the mass of green coffee is much smaller. Resulting in you most likely need to work with different guidelines for your temperatures (yellowing, crack, and end).
2. Working with a Loring you need to make sure your "Stack", "Return" and, "Inlet" temperatures are lower than on an 80%+ capacity roast. Doing that will enable you to have more control and work with a larger range of Burner Settings.
3. To allow you, even more, control it's useful to work with a "pyramid" burner distribution - having your highest burner setting later in the middle part of your roast. Building up from the start and down from the yellowing.