I would certainly buy it if possible but if you want mostly dark roasts, do more investigation as I can not help more.
Positive Product Points
1- Impressive show piece 2- Well built 3- easy to use 4- Adapts to user preferences 5- Wide roasting capability
Negative Product Points
1- Chaff separation and collection can be improved 2- May be low on max heat available 3-Warning beeps too high pitched 4- May be a little high priced but worth it
As far as I know my Hottop is a very recently produced unit as the shipment had just come in to “Our Coffee Barn” when I placed my order only about three months ago. So I assume that it is typical of all recent machines. I purchased the unit out of state to miss the tax and also obtained free shipping and beans. By the way they shipped the same day the units came to them and have proved to be very knowledgeable and helpful since then.
It is a beautiful unit and as far as I can see it is very well made of first class parts and materials and should last a long time. My first roast was a disaster due to my inexperience with it. The process seemed so slow for the first 15 minutes that I was not prepared for the rapid progress as the cracking started and the roast turned out to be a very dark French before I ejected it. I threw it out because, not only was it way beyond what I like, it tasted baked.
My next roast was lighter but still had a very pungent baked flavor and I think it went into the ash can too. At this time I figured I had to learn more about what was going on.
In order to understand how the automatic control system regulated the roasting temperatures, I first plotted the panel temperature readout for each minute from cold start to 26 minutes without adding beans and I found that the roasting air temperature was controlled in a smooth upward curve from zero to the maximum. I call this the no-load air temperature. The drum temperature is not known but must follow along at a higher level and the coffee beans are roasted by a combination of the heat from the drum and the air. On my roaster the highest air temperature reached is 410 degrees Fahrenheit at about 19 minutes from cold start. This seems a bit low as it begins to drop after that. The bean temperature measured by an infrared thermometer as they drop into the cooling tray runs 20 to 30 degrees above the panel readout at the time of ejecting the beans.
It was obvious that the normal five minute preheat time warmed the unit up to only about 200 degrees and the gain was steady but somewhat slow after that and I knew from roasting in the oven that the beans were put in at a temperature of 450 to 500 degrees and a few minutes later you had roasted beans. Coffee beans should not be held at low temperatures too long as it volatilizes the oils that carry the flavored esters which give the drink it’s bang and will taste dull and baked. I realized then that all I had to do was to sneak up the curve to some higher temperature and dump the beans in for a quicker warm up and shorter roast time. I am not able to hear the high-pitched beep at the designed five-minute time to add beans so I use a stopwatch anyway.
The user has the ability to choose the degree of roast and whether the process is long and slow or faster for a brighter roast, which brings out more of the aromatic flavors in the beans. The five minute standard preheat allows the slowest roasting and by selecting a longer preheat to a higher starting temperature the shorter roasting times can be obtained. For my own taste I prefer the faster roasting to between first crack and slightly into second crack. Some users have complained of too much voltage dependency where they don’t get hot enough for the darker roasts, however I feel that the actual temperatures are regulated automatically by the control system and my voltage stays up ok even when the heater coils come on. I do not feel that the machine is very sensitive to the ambient temperature as the polished surface stops heat loss and there is very little cold air drawn into the roaster. The one thing that will be affected is the warm up or preheat, because the entire machine is cold. I do not use a pre-selected time for roasting and feel that one should always use the manual eject at the desired color or temperature or other indicator of roast level. I use preheat times from 8 to 14 minutes depending on the type of beans and the kind of roast that I want.
Further Testing Hottop Roaster
Many of the reviews that I have read on the Hottop Roaster find problems with the heat output at the upper roast level and have installed variacs to hold or increase line voltage for more heat. I agree that in cases where there is low line voltage or input voltage swings during roasting or from one roast to another, the variac is needed for uniformity. Observing the color of the heating coils clearly shows a designed heat modulation after about 5 minutes from cold start. When the beans are put in the heat comes back on full long enough to bring the temperature back to the design level. The coils do go cold again at about the 19minute point that causes the droop in the curve.
. The blue bean-roasting curve, taken by a multimeter probe directly in the tumbling beans, shows the need to start at a higher roaster temperature. My information acquired to date is that the roasting temperature should proceed steadily upward and definitely not flatten or stall anywhere. The proceeding curves clearly indicate the drop in heat input in the upper roasting level that is no doubt one of the causes of other users problems in wanting the darker roasts. At present I seldom want a roast above a dark Full City so am not bothered by the low final temperature.
The thing that gives this Hottop roaster its wide roasting capability is this long heat up of the air and drum. This gives the user the ability to favor the bright aromatic character of the beans by selecting the higher starting temperature which also yields a shorter roast cycle and to bring out the depth of body in the beans by pushing the eject time to a higher level. To subdue an overly bright bean such as a Kenya he would introduce the beans further down the curve for a longer warm up period.
The roasting is very uniform and consistent as long as all variables are the same. All in all it is a fine machine and real pleasure to use. I am not able to Comment on the heavier roasts since our preference is for the lighter City and Full City roasts below second crack and I have heard complaints from some folks who were not able to reach the darker French and Italian roasts. I know that since using three other not very satisfactory roasters during the last several years I will enjoy this one.
Can't be better. Swell people, very prompt shipping, Knowledgeable and helpful