Gene Cafe, part 2

Meet The Gene Cafe!!
by Dave Borton

Big, sleek, cool knobs, nice contours, jet black, and ever so inviting...the Gene Cafe. It almost calls out your name, have you noticed?

But why the Gene Cafe coffee roaster?

Because you are s-e-r-i-o-u-s about your hobby, that's why. You want a large capacity machine (10.3 ounces) that can crank out back-to-back roasts which turn out as consistent as a clock tuned to Greenwich. You have made a good choice. But what do you need to know when Mr. Brown walks the Gene up to your front door?

First, read your manual. Take some time to familiarize yourself with the machine, particularly the different uses of the dials. When your beans are in the middle of the 1st crack, it's a little late to learn your machine. Like I advise with all home roasting appliances, buy 5 pounds of a Colombian or Guatemalan bean that handles heat well and learn your Gene. Go very, very deep for a couple of roasts, learning the Gene's paces. Then try a couple of lighter roasts. There is no substitute for trying the same bean at a variety of roast levels.

How Does the Gene Roast?

The Gene most resembles a professional drum roaster. Hot air enters the unit and heats the tumbler wall, the partition within the tumbler, and to a lesser degree, the beans themselves.

The beans, however, derive most of their roasting heat in the Gene Cafe from the bean mass itself. This means that the Gene Cafe roaster will take a longer period of time to get the bean to the same roasting depth than does a fluid air bed such as the FreshRoast Plus or the I-Roast 2. As such, unlike the I-Roast 2 where your roast could be done by 10 minutes, the Gene often hasn't even reached the 1st crack in the same amount of time. Relax, that's normal.

Working with the Gene Temperature Settings

Let's keep this simple. Higher grown beans are denser and handle heat better. As such, the higher the altitude at which the bean was grown, the higher the initial temperature setting should be. These work well for a starting point so feel free to tweak and learn what works best on your unit. Try these:

  • Yemeni, Africans, PNGs, Central American (all high grown beans) - After preheating as described above, 480 until 45 seconds after 1st crack initiates. Turn unit down to 471 until roast is done to your cupping preference.
  • Brazilians, Caribbean, Indian, some Indonesians - depending on growing elevation - 471 until first crack plus 45 seconds, then 460.
  • Konas - 460/450
  • Decafs - 450/440

What you are trying to accomplish is to stretch the time between the 1st and 2nd cracks (without flattening the roasting profile) to create a sweet roast, shooting for about 3:15 to 3:30 between 1st and 2nd cracks. Always keep your roast moving upwards in temp and in the Gene, the bean mass temperature does this, even as you turn the temp setting down.

Tips with the Gene

  • Roasts that are cooled within the Gene's tumbler continue roasting 1/2 step more deeply in roast characteristics. For example, if you are shooting for a full city roast, hit the 'temp' button to initiate the cooling when the roast is at a city plus. (Smaller roasts in the Gene cool more quickly and do not move into the next roast depth profile).
  • Set the time to roast at 20 minutes even. This makes it easy to mentally compute and write down times for 1st crack, 2nd crack, and 'pull.
  • Use a scale to measure all your roasts. While the Gene will handle 300 grams, you might find it easier to manage 283 grams. Why 283 grams? That is 10 ounces and you can weigh the roast afterward and mentally figure out your water loss and write it down.
  • If you cool your beans using the Gene's cooling phase, raise the safety cover and direct a small office fan towards the unit.

Some would argue that it is better to cool the beans outside the Gene Cafe. Here is an easy way to do it, should you choose to:

Press and hold down the left knob ('Temp') for over 2 seconds. Dump the beans into a colander that is suspended in a shop bucket. Draw air through the beans, using a shop vac that is hooked to a nozzle out the side of the bucket. An easier arrangement is to put your warm beans on a screened pizza pan and put the pan on top of a fan that is suspended in some fashion, drawing air down and through the beans.

Note well: Put the tumbler back in the Gene as soon as you dump the beans, reinitiating a roast by resetting the right knob ('Time') and then immediately hitting the left knob to put the Gene into a cool cycle. Now go stir the beans.

More Tips with the Gene

  • Always use the tumbler stand when the tumbler is out of the roaster. You are asking for trouble if you try to set the tumbler down in anything but the designed and furnished stand.
  • Use oven gloves when handling both the tumbler and chaff collector. Gloves permit sufficient gripping strength.
  • Never, ever force the tumbler into the roaster slots. If you are feeling resistance, you aren't putting it in correctly.
  • Keep detailed notes. If you hit a perfect roast with a bean, you want to be able to repeat the roast.
  • Sumatrans often seem much lighter than their actual roast level. Ethiopian beans (dry processed) roast unevenly so expect a variety of shades of roast. * Make sure you empty the chaff collector after every roast.
  • Clean the tumbler and chaff collector every 25 pounds (or earlier if the Pyrex obscures your view of the bean), using a degreaser/cleaner such as Simple Green or a citrus product.

So now you have it. Grab the manual, read it, and get it on with those 5#s of Colombians. Put the Gene through all its paces. And when you are an expert, share your best tips and profiles on the Gene with the folks at

Roast on,
Dave Borton
Dave is an expert in planning vacations to Honduras. Visit his site: Guide to Honduras Travel and Vacation

Footnote: Read and pay attention to your user's manual. If at any time my information conflicts with your roasting machine, follow the manufacturer's directions.