For the past 4 months, we have been building our first 2 production coffee roasters. Today, the dream of researching, designing and manufacturing a professional coffee roaster came true.
So there we were, standing proud by our machine after having roasted the very first batch of coffee in the new generation of machines. But our victory was over far too soon when I realized that the coffee in the cooling tray wouldn’t stop smoking. We started scrambling for water, but couldn’t get anything close by to douse the glowing mass of beans with.
You see, a cooling tray acts much like a cigarette, for lack of a cleaner analogy. The beans in the tray is the “tobacco” while the fan would stand in for the unlucky smoker. The prize is the nicotine, or in our case, caffeine (not so different after all). Once you have a small ember (a stuck clump of water-damaged beans will do) in the cooling tray, the fan will provide it with copious amounts of oxygen in an attempt to cool down the beans. A small fire will inevitably ensue, sending us scrambling for anything to douse the now red-hot coffee beans with!
Unfortunately there was no water. But there was beer. It was a celebration, after all. George was kind enough to sponsor his, and our problem soon turned into a somewhat under-extracted coffee with distinct barley after taste. After seeing my creation glowing for a brief few minutes left me somewhat dumbstruck, but we soon found the problem.
It turned out to be the bean agitator design. I wanted to go with something new by using a swiveling design that allows the scrapers to move up and down. This created a “floating” effect, where the scrapers would lift to the top of the beans so that you can have a better, more even distribution of beans in the tray. However, I never gave much thought to the beans below the fins. The main bean mass lied untouched, which is good for cooling, but bad for embers.
Thankfully, the fix was simple enough. I simply turned 2 of the 4 blades into proper scrapers by adjusting their angles. Now they will dig into the bean mass and stir the bottom of the beans towards the top, while the other 2 blades will continue to level out the beans to ensure an even distribution of beans.
Tomorrow we’ll head back to the shop to run the drum in some more. After that, the real roasting will start! I just bought a bag of Costa Rica Brumelia Fancy, and I’m dying to make good use of it. Hopefully, that’ll go down with lots of crema instead of smoke!