Before you think this article is about if any of these processes are bad, it's not. Let me share my thought process and what I learned. In actuality, I really wanted a drum roaster. I literally almost bought a Mill City Coffee Roaster.
Problem was $7500 was way out of my ball park, so I started looking at eBay specials, craigslist binged, and almost bought a Sonofresco which is a fluid-bed coffee roaster. The issue I had with getting a drum was that they are not portable, propane and overall, they are best suited static. So prior to getting our brick and mortar shop in Los Alamitos, we were at farmers markets. I needed something portable and was also electric powered. That's when i stumbled onto this...
Reason for why i choose it: It fit the purpose of allowing me to bring it to farmers market to roast for the people to see it was freshly roasted. And i find it fascinating that know one else roast or boast about fluid bed style roasting. This method was invented by "Sivetz was a prolific author and inventor, publishing a number of books, tracts and articles on coffee quality and coffee technology. Along with his unique fluidized bed roasters, he also invented and produced a low temperature coffee extraction system point is you can still make good coffee with either it just depends on if you really care about what your doing, allowing people to enjoy the coffee. In order to create the seperation from what other people are doing i choose everything that is unique to Teofilo's "Single origin coffees from Philippines", how we roast all our coffees the fluid bed style coffee roasting style.
"Clean Hot Air Roasted Coffee"
A healthier better tasting coffee. Clean hot air roasted coffee produces a better tasting healthier product. Our coffee is less bitter and acidic producing a smoother, richer flavor. Why is our coffee better? Hot air roasted coffee uses convection heat to loft the beans for a very even heat transfer. The “Clean Bright Taste” people rave about is achieved by roasting the bean quickly and evenly while suspended on a bed of hot air. You will find this coffee less bitter then traditional drum roasted coffee." This is on of our coffee bags.
There are some clearly identifiable advantages to both methods.
-It is more efficient to heat the beans directly rather than heating a metal surface to conduct heat to the bean
-No moving parts in air roasting other than the air itself.
-Accurately gauge the actual bean temperature by inserting a thermocouple into the roasting chamber.
-Immersed in the hot air, they achieve a more even roast.
-Air roasting improves a coffee's acidity (creating clean, bright flavor tones).
-Drum roasting is that the operator has more control over the process: heat, air flow and humidity control.
-User must have adequate skill to judge all these controls well, inadequacy will surely lead to poorer coffee.
Possible cons: heating beans via conduction on the surface of a drum creates harsh, scorched flavors; they also note that the chaff of the coffee remains in the drum, generating more smoke, whereas air roasters have the advantage of blowing off the chaff.
Drum roasting creates more complex flavors and that the less efficient (slower) heat transfer allows for fuller flavor development.
Drum roasting has a positive effect on coffee's body (creating a fuller mouth-feel)
This article is written just from my experience and not advising anyone to do either just gives you options. 1st ask yourself do you want to do this? Does it fit your purpose? And these 2 systems exist don't hate either process, like i mentioned in the 1st part of the article i really wanted a drum roaster and still do but i've gotten so use to the fluid bed style and enjoy the curiosity of Michael Sivets he has so many theories on why its better. He wrote a coffee bible as the internet said, "Coffee Technology". In the end you decide what works best for your purpose.
I rather set a path instead of follow one.