Anatomy of a Roaster: what is the 'Trier'?

This is the first video in a series that will describe the Anatomy of a Coffee Roaster.
The Trier is a tool used to take samples of coffee from within the roasting drum as the roast is progressing. The production roaster will use the colour and aroma feedback to make decisions about where to take the batch and when to stop roasting and eject the batch from the drum.
This video also describes the difference between to trier used by Loring and that of a traditional drum roaster in Probat.
I hope this helps explain this piece of the equipment.
Stay tuned for the next in the series.
James