hey everyone.

quick question: who here tilts their popper when roasting coffee? people say that it is a technique for improving airflow, but i'm not sure i'm convinced. When I do it, I can clearly see beans that sit on the "low side" of the roasting chamber and don't move for quite some time. I also notice some tipping in my roasts and wonder if this might be the reason.

What is everyone's opinion of tilting their popper when roasting?

I haven't done popper roasts for a long time, but I used to tip the popper at the beginning of the roast, when the beans were denser and the air couldn't really stir them quite as well; after the drying phase, they spun around by themselves pretty well and I put the popper flat again.

If they don't make it to the stage where they spin around with the popper flat, I would think you're overloading it a bit.

It creates a more efficient airflow, and therefore gets more even roasts with higher loads. The beans tend to circulate, going up on the upper side, and down on the lower side. This is less entropic than the classic fluid bed bubbling.

It is my experience that tilting the popper has only one real benefit; it allows movement of the beans when the batch size is so large that it would not be moving anymore without tilting. Hence it is a way to increase the batch size.

Yes the flow of beans that results is less "entropic" but this, in fact, is a bad thing in my view. As mentioned by the OP, the flow of beans is often uneven. Thus there are some beans that can be left in the hot portion of the popper for extended time and may result in over roasting of a portion of the batch and possibly charring of a few beans.

Do not get me wrong, I do tilt my popper to increase the batch size. This advantage does outweigh the disadvantage mentioned but as soon as the beans have lighten up I remove the tilt. YMMV