The window into the soul of a coffee roaster...
The sight glass is the one way someone roasting coffee can directly visualise what is happening in the drum of the coffee roaster. I think of it as being akin to a portal in a spaceship, the eye piece of a microscope, the periscope of a submarine, the webcam on your laptop.
There are two key visual changes that occur in coffee beans as they heat up during the roasting process. The first is change in colour, starting off light yellow/slightly green, moving to a darker yellow and then (depending on ending roast degree) brown to perhaps black (the latter a horrible result in my opinion). The sight glass allows the coffee roaster to confirm visually what the roaster's thermocouples are describing quantitatively from a thermodynamic perspective.
A few announcements...
Firstly, happy holidays! I hope that you are healthy and well and that you are winding down to a wonderful and relaxing holiday period surrounded by the people you love the most.
Secondly, our family is taking two weeks of holiday between January 10 and January 24... so there will be no roasting during that period. Last orders prior to the holiday will be taken Friday January 5, 2024 for roasting Saturday/Sunday January 6/7, 2024 and dispatch Monday January 8, 2024. Roasting will recommence on the weekend of January 27/28.
And finally, if you've been wanting to efficiently try all of the four different espresso roasts that Garage Roasters has to offer, I have added a Blend Sample Pack to the product list which offers up 250 g of each of the four blends so that you can taste the differences between them all.
Buy the Blend Sample Pack