The Pullman Tamper

It's a pretty common question; both roasters roast coffee, but the Gene is a lot cheaper than the Hottop and has a growing fan base, while the Hottop looks a much more serious unit and has a lot more programmable options. "Which one should I buy?"

Read the review of the Gene Cafe and the Hottop

I was faced with this same question in early 2008. I liked the look and functionality of the Hottop but the Gene was at a compelling price, and on the advice of some respected coffee authorities I purchased the Gene Cafe to evaluate its suitability for my personal use. Soon after this I had the opportunity to use a Hottop D roaster and subsequently purchased a Hottop B as well as a P upgrade kit so I could test these newer devices. The best advice I could give is to read through the review. As an owner of both, I rarely use the Gene Cafe now as I find the Hottop works best for me, however it's important to establish that there is no one perfect roaster for each person. Both roasters have their strengths and weaknesses, so with both units your choice will largely come back to which set of strengths are most important to you, and which set of weaknesses you can live with more easily. The review outlines these and helps you to decide which you are more likely to prefer.

In brief however, the Gene is cheaper, provides greater visibility of the roast, is very good at removing chaff from the beans and allows you to start a roast immediately on finishing the previous one; however it is quite noisy (making it hard to hear the bean cracks), is built mainly of plastic and doesn't give you a good indication of bean temperature. The Hottop is very quiet (making it very easy to hear the bean cracks), is built mainly of metal and the temperature sensor is located inside the drum giving an accurate indication of bean temperature; however it is more expensive, it tends to leave more chaff on the beans and in the roaster and has a required cool-down period which you can't get around if you're in a hurry to start your next roast. The Gene has a clear glass drum and a noisy fan and noisy motor, so you roast more by sight than sound. The Hottop has a viewing window in the end of the drum with a quiet fan and quiet motor, so you roast more by sound than sight. The bean cracks are important and definite milestones in a roast, whereas while bean colour is important it tends to be a more gradual change rather than a clearly defined point you can precisely identify, and the exact colour varies under different lighting conditions. These are some of the reasons I personally prefer the Hottop roasting process.

The overriding advice remains however to identify your needs and determine from reliable information (such as the review referred to) which set of strengths and weaknesses will best suit you.

If you'd like a bit more info on this, read on to our next article '10 reasons to consider a Hottop'

We'll be honest, we prefer the Hottop to the Gene Cafe. This isn't because the Gene Cafe is a poor roaster, or because we make more money selling Hottops because neither are true (believe it or not). It's simply because we believe the Hottop does the better job at roasting coffee. Being roughly twice the price so it should, but we believe it definitely does. Here are 10 of our reasons:

1. Hottops are the only roasters readily available in Australia that allow you to save roast profiles to memory for simple subsequent roasts
   
   
2. The Hottop is the quietest roaster on the market, with a quiet motor and drum operation, and air flow via a quiet rotary fan (not a blower)
   
   
3. The built-in cooling tray on the Hottop means your beans are cool within four minutes of the roast finishing. This compares favourably to others which use internal cooling where it can take more than 10 minutes to do the same.
   
   The importance of cooling is explained in the first edition of BeanScene (p.65), where Ross Quail, Master Roaster at Jasper Coffee writes: "...a coffee that has taken a long time to cool presents itself as somewhat 'flat', 'lifeless' or with a 'baked' flavour...", a statement backed up with some real-world testing mentioned in that article. And he doesn't sell roasters either, he just knows what brings out the best in coffee and it sure ain't slow cooling. Sure, you can make your own bean cooler out of a desk fan, a colander and a few other btis and pieces, but you can also make a roaster out of a breadmaker and a heat-gun, and one of the reasons you're here is because you want a total roasting solution, not odds and ends, right?
   
   
4. Its design makes it easy to fit a bean mass temperature probe so you can measure the actual bean temperature, rather than just the temperature of the air coming out of the roaster (which has little relationship to the bean temps). If you roast differing capacities of beans the difference between the bean temperatue and the air temperature will change, so not having a bean mass probe makes it very difficult to repeat a roast profile on a different amount of green bean. Bean mass probes can be purchased pre-installed when buying a Hottop from Things Coffee
   
   
5. Hottops give you control over the heater power AND the fan speed, giving you more flexibility over your roast
   
   
6. The use of smoke particle filters means it's a low smoke roasting solution, making roasting indoors far easier than with filter-less devices
   
   
7. The roaster is built around a metal chassis with chromed steel panels and a stainless steel drum, rather than a plastic shell and a glass drum
   
   
8. Because they heat via radiation rather than heating large volumes of air, the Hottop's 750W element consumes less power that some other roasters
   
   
9. The Hottop has a forced cooling and preheat cycle to ensure the drum is at the same temperature each time the beans are added. This leads to more repeatable roasts as the starting temperature is always the same
   
   
10. At the time of writing, the Hottop B is the only roaster that can supply continuous intermediate power, which means perfectly smooth heating and no chance of burning beans - some other roasters apply 100% power until setpoint is reached, and then no power at all until it drops below setpoint - if you ask the B for 60% power it gives a continuous output of 60% power.
    
    
    oh...
11. Unofficially they can roast over 500g of green beans. This isn't recommended of course and we'd never encourage that, but in our testing they handled 350g, 400g and 500g just as well as 250g, unlike some other products which started burning beans as soon as we passed 300g.

One roaster, three controllers - which one is best for you? Read through the following comparison to get a brief on how they each work. You may also like to check out the B and P roasting videos further down which demostrate the controllers in action.

Hottop B

The B controller has a simpler segmented LED display control panel and 3 memory locations, though by no means is a cheaply made unit. Before you start the roast, you enter simply a total roast time and target temperature and start the roast. Once it's underway you then manually control the heater power and fan speed to build a profile as you go. Once the roast has finished you can save the program you just created, however there's no way to edit it at all other than performing another roast and making the adjustments as you go once again. Initially it has a steeper learning curve than the P controller as you have to learn the thermodynamics of the roaster, i.e. how long it takes for a control panel change to show up in the drum. I stalled the first few B roasts while learning this, however now I've learnt this I find it the more flexible of the two controllers because you can adjust all parameters at any point in the roast.

The thing I like most about the B controller is the ability to control every aspect of the program at any time - and it's a fair bit cheaper than the P too! It is undoubtedly the most flexible Hottop controller. It's also great that it can supply continuous partial power - if you ask for 60% power it will give continuous 60% power, rather than the P which will give 100% power until it reaches a setpoint and then switch off the heater completely. The B's roast profiles are smoother than the P's.

The thing I dislike most about the B controller is the fact you can't erase a program completely and start with an empty program or edit the program upfront. This means if you roast with an existing program (as you often would want to otherwise what's the point in having them) you sometimes have to do battle with the pre-programmed adjustments coming in before you want them, e.g. if you decided you wanted the fan to come on later you'd have to wait for it to automatically turn up and then turn it back down.

Hottop P

The P has a fancy LCD multi-colour control panel with silicon rubber buttons and 10 memory locations. Before you start the roast, you create a program using 8 different roasting segments, each of which can have a setting for temperature, time and fan speed. Initial programming is slow but once you've done one you can copy and paste to other memory locations and refine the roast parameters. Once the roast is underway you have limited control, being able only to adjust the temperature of the active segment. Essentially the philosophy is 'Program, then roast' and I found this preferable over the B controller when getting started, but a little limiting once I'd built up more experience. Since you're telling the controller what temperature to aim for, you don't have to worry about learning the thermodynamics of the roaster as you do with the B controller as the P's brains will take care of actual heater power as required to reach the set point at the required time.

The thing I like most about the P controller is that while you never leave any roaster unattended, it's the most 'set-and-forget' solution and you don't have to monitor it as much as others during the roast. You create the initial program and can then pretty well sit back and let it follow the program until it's time to eject the roast. This makes it a very 'sociable' roaster, i.e. you can set it going while you have friends around and can stand around nearby and chat, keeping one ear out for the cracks and monitoring the change of smell without having to keep too close an eye on the screen, and only getting involved to accept the safety beeps and to eject the roast. By contrast the B's programs are time-based so it's sometimes necessary to make a change a bit earlier or later time-wise than you may have when you created an initial program (e.g. if ambient temperature is quite different), which means you have to pay a lot more attention to the control panel. The P is also a very schmik looking controller, far 'prettier' than the controller on any other domestic roaster be that Hottop or anyone else, so if someone wants to take a closer interest there's plenty to see on the control panel and in the viewing window.

The thing I dislike most about the P controller is that it doesn't look ahead to the next roasting segment's parameters when controlling the current one. This means if it's got 30 seconds to go and is slightly above the set point, it will drop off the power to bring it back down even if the next segment requires it to increase the temperature. The amount of thermal energy stored in the drum means this doesn't adversely affect the roast but the engineer within me would prefer it to look ahead and behave accordingly. Another disadvantage with the P is that the heater power is either full on or full off - it will supply 100% power until it reaches the setpoint and then turn the heater off completely until temperature drops below the setpoint or the next segment is reached. It can't supply partial power like the B, so it tends to roast in steps rather than a smooth curve. With good program design the off time can be as little as 20-30 seconds at the end of each segment which has no effect on the roast results but it's worth noting for the purists who would want absolute smooth power.

We roasted 250g of Mt Gabbana Forest Estate Ethiopian Limmu in a Hottop roaster fitted with the KN-8828B controller. This video gives a brief overview of how to use the B controller and shows the roasting process and the excellent result achievable, as well as some of the flaws.

Play hi-fi video stream (58Mb, ~23 minutes)

Play lo-fi video stream (7Mb, ~23 minutes)

This is the profile we ended up achieving and the times and adjustments we made to achieve it:

We roasted 250g of Brazil Daterra Sweet Collection in a Hottop roaster fitted with the KN-8828P controller. This video gives a brief overview of how to use the P controller and shows the roasting process and the excellent result achievable, as well as some of the flaws.

Play hi-fi video stream (66Mb, ~26 minutes)

Play lo-fi video stream (7.5Mb, ~26 minutes)

We roasted 250g of Ethiopian Mao Horse Harrar in a Gene Cafe. This video gives a brief overview of how to use the Gene Cafe, showing the roasting process, the very good results achievable, and some of its flaws.

Play hi-fi video stream (56Mb, ~22 minutes)

Play lo-fi video stream (6Mb, ~22 minutes)