Coffee Blog - The Coffee Lovers’ Blog

With two bean roasting sessions behind me I cannot believe that I didn’t start roasting my own coffee beans a long time ago!

The Hottop roasting machine has so many options and settings which can be tweaked that it seemed that I may have purchased a sledgehammer to crack a nut (OK a bean!), so I am still using the machine on ‘Auto’ mode at the moment.

The last roasting session produced a lovely mid-roast, one which I was keen to duplicate on this, my third roasting session. This should be relativley easy to achieve as I am still using the same green beans as the previous two roasts.

So in ‘Auto’ mode and an 18 minute roasting time the following results were observed.

The first crack started after 13 minutes 11 seconds at a temperature of 367 degrees f, slow at first but more speeding up at just over 30 seconds later at 381 degrees and very rapid after 14 minutes 30 seconds at 392 degrees.

The second crack started around 15 minutes 55 seconds into the roasting at a temperature of 398 degrees f.

As with the second roasting session I ejected the beans with 1 minute 30 seconds of the roasting session left (16 minutes 30 seconds of roasting time elapsed). The displayed temperature was 407 degrees f.

The second crack was very rapid at the time and I wished that I had ejected the beans a little earlier, perhaps 30 seconds earlier. There was more smoke this time than the second roasting, but nowhere near as much as the first roasting (or should I say burning) session.

An update on the second roast
When I went to find a suitable storage container for these beans I took a look at the beans produced from the second roast. They were stored in an airtight glass container (as per the suggestion in the Hottop manual) but there was noticeable moistness on the beans and within the jar. I wonder if I put the beans in the jar when there was still a little heat in the beans?

I will look at the beans from this third roast in a couple of days to see if they go the same way.

A warning
The problem with having a home coffee bean roasting machine is that you are so keen to move on to your next roast you will end up roasting more beans than you can use!

After learning an awful lot from the first roast with the newly acquired Hottop home roasting machine, I was keen to see if the second coffee bean roasting session produced better results.
The first roast was far to dark, some would say burnt, so I decided to go for a slightly lighter roast this time.

Still in “Auto” mode, which defaults to 18 minutes, the next batch of 250g of green beans sat waiting for the machine to pre-heat. As soon as the roaster beeped to indicate it was time to add the beans they were added through the bean chute.

The Hottop manual does have a section which lists approximate times that you should see bean colour changes, the first crack and the second crack. If anything the beans were progressing slightly quicker than the manual said they would, but it was a warm day and the ambient temperature was over 20 degrees C so this may have caused this??

The first crack happened almost two minutes ahead of schedule so the second crack was expected early too.

Just a few seconds into the second crack I ejected the beans early as I didn’t want the roast as dark as last time.

The beans were ejected out onto the cooling plate and were noticeably lighter than last time, with just a hint of a few oil spots.

On the face of it, a much better roasting session.

Roasting details

Beans ejected after 16 minutes 30 seconds
Temperature of roasting machine at time of ejection, 408 degrees F
Observations - Rapid cracking (second crack), much less smoke than first roasting session

As mentioned in my previous post, we have today taken delivery of a Hottop Home Roasting Machine (KN8828-P).

This machine was purchased from UK company “Has Bean” following a discussion with Sarah (the owner of Has Bean).

Initially we had decided upon the Café Gene Coffee Roaster, but decided to push to boat out and purchase the Hottop KN8828-P instead.

The mostly stainless steel Hottop certainly looks the business. In fact, it wouldn’t look out of place behind the counter of your local coffee shop.

The roaster comes fully assembled and only needs the bean chute cover to be inserted.

We also purchased a 2Kg bag of Celebes Toraja Kalosi green beans. Sarah kindly sent 250g samples of Sumatra Lingtong, Toba Sulawesi Espresso Brand and The Breakfat Bomb beans too.

The reason we purchased a 2Kg bag of the Celebes was so that we had sufficient beans of the same batch to try various settings on the roasting machine without introducing different beans for different settings which wouldn’t have given comparable results.

The first attempt at roasting coffee beans with the Hottop didn’t exactly go to plan!

Keen to get going we quickly skimmed through the excellent manual supplied with the roaster and decided to use the “Auto” mode to start with. In Auto mode you still have control over the roast time, but everything else is taken care of by the machine. More experienced users will probably end up with their own roasting “recipies” which can be saved as programmes within the machine and easily recalled.

So we switched on the machine, selected Auto, confirmed the default roasting time of 18 minutes and started the machine going.

The first stage if for the roaster to get up to temperature (this take place BEFORE adding the green beans). When the machine is up to temperature a beep is heard and the on-screen display indicated that it’s time to add the beans.

We added the beans and watched them rotate around the internal drum as the display showed the internal temperature continue to rise. The machine quickly started to make a grinding sound as the drum rotated. Having not used a coffee roaster before we didn’t know if this was just caused by parts of the machine expanding as the temperature rose.

A minute later and the grinding was getting louder, and on close inspection of the rotating drum we could see that the drum wasn’t rotating smoothly - on each rotation there was a slight pause as if the drum was getting stuck. Seconds later there was a louder grinding sound the drum stopped rotating. Thinking this wasn’t right we pressed the Back/Eject button to abort the roasting process. This ejected the beans to the cooling tray below.

We allowed the machine to cool down and started again. This time the drum didn’t rotate at all during the pre-heat process so we aborted straight away.

Time for a quick call to Sarah at Has Bean. I explained the problem and Sarah said she would get Stephen to phone me once he had finished the current roasting he was working on.

We decided to take the machine apart (a process required to clean it anyway, so we weren’t invalidating the warranty) just in case we could see what the problem was. There was no obvious problem so we re-assembled the machine.

Waiting for the call back from Stephen we decided to give it one more go, using the same 250g of green beans we used for the first roasting attempt. This was a mistake, but more of this later.

This time the drum rotated properly and the grinding sound had gone. Perhaps something got dislodged slightly during transit.

So we were on our way; the beans changed color during the process as time passed and the temperature rose. The “first crack” of the beans arrived as expected, followed by the “second crack”. A quick look at the timer showed a few minutes left as the beans darkened and smoke stared escaping from the machine. This was expected, but not quite the amout that was actually generated - more than enough to set off two smoke alarms spread over two floors!

At the end of the process the beans were ejected and the result was a very dark roast (some would even say burnt) and a very oily coating. We then realised that the first aborted roasting attempt had already roasted the beans for a few minutes so we should ideally have thrown the batch away, or at least reduced the roasting time for the second attempt. Well they say you learn from your mistakes!

On reading the manual in more detail it does actually suggest throwing the green beand away if you have to abort the roasting process. Having had to open all windows and doors to get rid of the smoke just generated, we would quite agree!

So lesson learnt, we let the machine cool down, ready to try again with the benefit of our new found knowledge.

We will bring you details of the next roasting soon.