As demand has continued to increase for our Artisan Roasted Coffee, we knew that we were going to have to add a new machine to keep up with the demand. Two weeks ago, responding to an ad on Craigslist of all places, I located a 2 lb Sono Fresco from another roaster who did not have time to devote to the art on a full time basis. I jumped in the car and drove to San Francisco and took a look at the machine which was clearly larger than my 1 lb refurbished model.
Returning today, the 2 lb was demonstrated and to my surprise it was quieter than the model I have now. Clearly, Sono Fresco had made many improvements in the past decade and this model is their flagship product. The beans were not as fluid in the chamber at first but as soon as the moisture was driven from the bean, more fluid motion activity began to emerge. The model is also just over a year old so it represents the newest technology that Sono Fresco has released to date. I am quite impressed with the resultant beans from its roast cycle.
The beans behaved normally during the roast cycle and we selected a profile 7 or Full City Plus Roast which took about 9 mins to complete. The other part of the process is cool down and we chose to override the profile and take matters into our own hands and cool the beans when the temperature reached 217 degrees centigrade. At completion or End of Roast, about 18 mins, 45 secs had elapsed.
What made this roast very enjoyable is that it also answered a long standing question that I have had concerning carmelization of the bean. Some maintain that an air roaster cannot properly carmelize as a drum roaster does. In reality, this argument makes no sense to me since the Maillard Reaction which is non enzymatic browning is evident in both technologies. If the Maillard Reaction is present so is bean carmelization where the sugars and specifically sucrose lead to the darker look to the bean. Any sweetness left is related to the uncarmelized component of the roast.
So, there it was....*bean carmelization was clearly evident in our test roast today and I also noted the larger roaster also brings a level of roast stability I have not completely achieved in my 1 lb roaster. The larger the roaster, the better roasting profile can be achieved and repeated. There is a law of diminishing returns but I am hoping to realize increasing returns with my new machine that can churn out 6 lbs of fresh roasted coffee per hour. 48 lbs of coffee per day at this point is fine. When the market demands that we produce more, we will look to add more roasters. It's a simple law of economics to follow.
In conclusion, whether you roast on a drum or in an air roaster, carmelization is realized as soon as a process called pyrolysis where the chemical composition of the bean is changed and CO2 is released. This release of CO2 also protects the bean somewhat as it continues to develop and release flavor aromatics.
These flavor aromatics are present as long as the bean chemistry has not been roasted to a point where they are exhausted. The resultant coffee is one that has excellent body and a very good taste with some sweetness. In lay terms, it is called pure yumm!
Here are some images from the test roasts we did on the 2 lb hereby known as "Big Red".
Green bean at roast start Bean browning evident