Quick Background: I bought a coffeeshop/bookstore 6 months ago. Love coffee and the culture etc. I'm in a remote area and have few local roasters. The one I use is that which I judge to be the best. But I want to understand more about how the roast affects the beans. My first two roasts were an amazing example.

So I begin my quest to become a shop-roaster. I figure buying and installing a shop roasting system with zero experience would be like buying a brewery without ever having home-brewed. I wanted a Quest but they're not available for a while so I bought a Hottop to abuse and learn on.

Bean: Guatamala Finca Rosma
First Roast
I'm trying to maximize my green coffee purchases by minimizing the batch size, so I've chosen 150 grams to work with.

Started with the Auto profile, knowing that it would be hot for the amount of beans. I let it run, watched and took notes as best I could while it was happening.

Drop at 170
FC 7:40 and it seemed to continue right into second crack, I think
It was all moving so fast... I barely had the presence of mind to crank the fan to 50% at 8 minutes and then it was all going so fast that at the first sounds of what I thought was second crack I ejected. Looks like full cityish.

Second Roast
Next morning. I thought I wanted to slow it down and do a slower City Roast to taste and get a taste of the bean.
I felt more ready now...
80% power given the small batch
Drop 167
Fan 25% at 6 minutes
Fan 50% at 8 minutes
70% power at 8:30
First Crack started at 9:15
100% fan 0% power at 10:00 (not sure where i got the idea of 0%... but that's what I did)
first crack end 11:00 (i think)
Drop 11:20

TASTING
I took these to my shop to try the morning of the second roast. I use a Clever Dripper for tasting.

First Roast.
The fragrance was spicy and floral. The brew was the sweetest coffee I've ever tasted. Creme Brulee in a cup. Caramel, cinnamon and sweet vanilla. So amazing compared to all other coffee I've tasted (not as much as I want it to be).

Second Roast.
Similar spicy floral aroma with a slight mustyness (grassyness?). None of the sweetness of the first roast but more of what I'd call floral spiciness and definitely grassy but what my uneducated palate would call flat. Is this baked beans? Did stretching the time to 1C kill the sweetness or is that just because I didn't go through to 2C? I have so many questions that I look forward to answering by doing more roasts, although thoughts from the scrum would be appreciated as well.

Cheers,
Eric

Try searching for roast profiles.

Try to avoid roasting the outside fast then stalling the roast. This means try a lower dry cycle then ramping up the heat then stretching from 1c to 2c by reducing heat a bit to compensate for the beans producing their own heat.

If you go too high too fast then cool it off you roast the outside too dark and inside too light and it will be grassy

Not an expert...

I jut wrote up an article on a computer control board. In it is a graph of two roasts.The temperatures are not relevant to you as the Hottop display differs quite a bit from the probe temperatures which were recorded, but my point is that these two roasts differ just a bit but the results in the cup were quite different. Small changes can make a big difference when you get close. The article is HERE.

Nice article, Randy. I may end up adding hardware in the future. I'm going to experiment without added TCs etc for a while, but that system sounds like it's pretty sweet.

First Roast.
The fragrance was spicy and floral. The brew was the sweetest coffee I've ever tasted. Creme Brulee in a cup. Caramel, cinnamon and sweet vanilla. So amazing compared to all other coffee I've tasted (not as much as I want it to be).

I tried this batch again after 2 additional days rest in a non-airtight bag. I've never seen such a degradation in experience. Everything was still there, the spicy vanillaness, but they were so diminished as to make the taste much less amazing.

If other people hadn't had the same impressions as I did, I would chalk it up to first roast excitement. But I shared both tastes with others who had the same opinion.

I've read that roasted coffee loses it's luster quickly but have never experienced it like this. The other 3 roasts I've tested have been much more static in tasting over time. Why would one batch degrade so much more than others?

Did you read the Hottop manual for guidance on roasting? Randy G wrote a good description of how to roast, and there are links to the PDF on the Hottop web site.

The reason Randy suggested installing BT / ET thermocouples is to give you better information about the bean temperature. Due to the physical location of the internal probe in the Hottop, it may not give you useful information with only 150 grams of green coffee. It takes about 200 grams to get the probe into the bean mass. Just take a look at the rear wall of the drum, and you can see the internal probe.

Randy G. wrote:I jut wrote up an article on a computer control board. In it is a graph of two roasts.The temperatures are not relevant to you as the Hottop display differs quite a bit from the probe temperatures which were recorded, but my point is that these two roasts differ just a bit but the results in the cup were quite different. Small changes can make a big difference when you get close. The article is HERE.

I just purchased and installed this board in my hottop. It's great! I totally agree that the displayed temperature can be drastically different from the temperature measured by the thermocouples. From cold start the display temp can be 50 degrees or more below the real temperature. The back of the roaster acts as a heat sink and keeps the factory sensor cooler until the mass of the roaster warms.

It's not so bad on subsequent roasts if you make another roast back to back.