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I've just purchased a Fresh Roast SR500 home roaster. I have no experience roasting coffee so I'm looking for some basic principles to guide my efforts. After two batches so far, the first, done according to the directions, was horribly undrinkable, and the second, while drinkable still wasn't very good. The flavor is a somewhat bitter aftertaste. The coffee is described as a wet processed fruity Java bean. I have so many questions I'm not really sure where to begin.

After watching several YouTube videos it seems like every one is different. A professional roasters site advised the roasting time should be between 10 and 15 minutes for all roast levels. But that still leaves the question of how much heat and how to adjust that during the roast.

Are there any straightforward principles for how to adjust the roast in respone to the taste I've gotten from my first attempts? Or any guidance on differences in roasting light vs Full City which would be the darkest I would do?

I really don't want to reinvent the wheel here and waste a bunch of coffee beans in the process.

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I have been roasting with the FreshRoast SR 500 for several months and have seen wildly differing advice from a variety of sources. Recently I found information from a few sources that when combined have resulted in some really nice roasts.

The first piece of information I found was the temperatures for the heat settings of the FreshRoast SR 500:

|  Setting  |  Temp  |
| :-------- | :----- |
|  High     |  490   |
|  Medium   |  455   |
|  Low      |  390   |  

The second piece of information I found was the temperature at which coffee beans begin a process called pyrolysis. At about 400 degrees Fahrenheit pyrolysis begins in coffee beans. Pyrolysis is the process of chemical change within the bean that generates heat. When this process happens in coffee we hear it as a popping sound known as first crack.

In the SR 500 a temperature setting of Medium is high enough to raise coffee beans to this temperature. I had been using a high heat setting to roast coffee, and the resulting beans had a very smoky flavor, which was not very pleasant.

Additional research yielded some additional wisdom that I find sound.

1. Apply adequate energy at the beginning of a roast
2. Make sure that the bean temperature progression always decelerates
3. Make sure that first crack begins at 75% to 80% of total roast time

This information is sound when trying to roast to a City or City+ level, which is fortunate for me as I am aiming for a nice medium roast for pour over coffee.

According to an information card I received from Sweet Maria's with my first order of coffee from them, city/city+ is achieved at the tail end of first crack at a temperature range of 415 to 435 degrees.

Applying adequate energy at the beginning of a roast is not the problem with the FreshRoast SR 500. I find that the roaster applies too much energy and roasts much too fast. If anything, I needed to find a way to slow down the drying phase, as the beginning of the roast is often called, and developed a procedure for stretching that out with this roaster.

I start by using an interval timer app on my tablet designed for use with interval training exercise to precisely time the steps in my process. To slow down the initial drying process I alternate heating for twelve seconds and cooling for six seconds and repeat this cycle for twenty-four intervals. The interval timer helps me remember what step I'm on and prompts me to switch the roaster from heating to cooling and back precisely. During this phase I apply only low heat with the fan speed on high. I also physically lift the roaster base and tilt the roaster several degrees away from vertical and rotate the roaster around its vertical axis. This agitates the green beans in the chamber and helps prevent scorching. I roast batches of 90 grams and find that this batch size also prevents scorched beans.

A decelerating temperature progression means that the rate of temperature rise should slow down during the roast. It doesn't mean that the temperature should lower but that the rate of temperature increase should be faster earlier in the roast and slower later in the roast. When the beans reach first crack there is a spike in bean temperature from the heat being generated internally by pyrolysis. In anticipation of first crack and knowing that the roaster will not respond instantly to changes in heat settings, I lower the heat just prior to first crack.

The advice to make sure that first crack begins between 75% and 80% of total roast time is only a guideline, but I find that adhering to it gives me very nice coffee. So with all of this information up front, here is how I apply it with the FreshRoast SR 500.

I begin by preheating the roaster using high heat and the fan control at the 3 O'clock position. This allows all of the roaster parts to absorb as much heat as they can and prevents the roaster from sucking heat away from the beans. I follow a set rhythm while roasting one 90-gram batch at a time. While the beans are being cooled by the roaster after completing the roasting cycle I weigh out the next 90-gram batch. When the roaster stops I immediately pour out the beans into a tray, turn the roaster back on using low heat and low fan speed, clean out the chaff collector, and load the next batch of beans into the roast chamber.

Preheat the roaster for 2 full cycles at a fan speed of 3 O'clock and using high heat. Run the roaster on low heat and low fan speed between batches.

Start with a roast time of 2.8 minutes. Roast 90 grams per batch.

|  Description         |  Heat    |  Fan Speed  | 
| :------------------- | :------: | :---------: |
|  \*Drying Cycle      |  Low     |  High       |
|  @  1.9              |  Medium  |  1 O'clock  |
|  @  1.1 (FC) \*note  |  Low     |  "          |
|  @  0.5              |  "       |  3 O'clock  |
|  B4 End of FC        |  Cool    |  High       |
  • Drying Cycle: Alternate heating for 12 seconds and cooling for 6 seconds. Tilt the roaster several degrees from its vertical axis and rotate it around that axis during this process. Repeat this for twenty-four iterations. Continue rotating the roaster until the first sign of first crack.

  • note: Stop rotating the roaster at the first sign of first crack.

I'm sure there is plenty of room for improvement in my procedure. Adding a thermocouple and noting the temperature during the roast would be very helpful in knowing what is happening while roasting. Sweet Maria's sells one along with a battery and a temperature probe as a package that is cheaper than what Amazon will charge you for the same components. It's about $30 from them.

I hope this helps either you or anyone else that might be looking for information for the FreshRoast SR 500.

  • 1
    I'm sorry but reading this answer makes my head hurt. I have been using the SR500 for 2 years now and I do not take any special steps for good results. I put approximately 125 grams of coffee in the machine, run it on low with full fan for ~ 2 min to dry., then bump it up to medium or high for the rest of the roast. Turn the fan down when the beans are flying around too much and stop it when it gets to where you want it to be. That's all it takes. – Mark Edington Sep 11 '16 at 1:40
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    Well, I'm sorry your head hurts. – sbicknel Sep 11 '16 at 3:07
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There is a goodish guide for your roaster here.

I'd also keep in mind that coffee has a cooling period after you "stop" roasting, where it will generally still roast to a darker level (or two). You need to try to finish your roast at a level or so lighter than what you are aiming for and let the coffee "cool" into your desired roast.

I might suggest that you roast at a lower level (lower heat) so that the beans move through the stages more slowly. This will badly suck up your time, but will also allow you greater chance of stopping the roast at the roast level you are aiming for.

Keep in mind that many of the descriptions you read for green coffee are done by people with extremely refined palates. No matter what coffee you roast, those fruit type descriptions are still hints and notes in the coffee, not it's overall flavor. Additionally the quality of the green beans you are roasting will affect the final quality of your roast. It's impossible to make poor green beans great by perfectly roasting them. You can, however, ruin high quality green beans with a poor roast.

When I started roasting, I was "lucky" enough to start with a cheap air popper. The advantage of that is that with a popper it is very easy to hear the "cracks" associated with roasting. My personal opinion is that the "cracks" are one of the few constants with beans that actually consistently indicate roast level. While there are other gauges out there (darkness and smell), they can vary with different varieties of beans. Eventually I moved to a machine where I couldn't hear the cracking at all, but by then, I had learned enough of the other cues that it didn't matter as much.

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Ya. All these convoluted processes. I'm happy with: - time = 9.9 - fan on high , temp medium - after about 2 minutes , fan on medium - when I hear first sign of frequent popping, temp to high until color is good - return fan to high and go into cool

1

Roasting coffee is like brewing beer...you can do it simple or you can do it hard...how complex you make the process is up to you. It's just coffee...play with the process and enjoy the output. I don't have sophisticated taste buds so easy is best for me. I pretty much use Mark Edington's method with a few changes. The FreshRoast 500 tends to produce an uneven roast so I have been stirring the beans with a spoon for the first 2 minutes. I am going to try the 'remove vessel and shake' method suggested at Sweet Maria's...seems simple and effective. Most coffee's go until the end of first crack (and figuring out 'end' is like listening for the last popcorn to pop...was that it? No! How 'bout now?...screw it, first crack ends when I say it ends! As soon as I think the beans are done, I pull the vessel off the heat source and dump the beans onto an aluminum baking pan so they stop cooking and cool off more quickly. Enjoy! OH...get one of Sweet Maria's coffee samplers...the difference between been varieties is amazing. Most of use tend to roast Arabica or Robusta beans. Turns out, there are other beans and they're nothing like what you may be used to. Also, Heirloom Coffees are worth a look...more interesting varieties here.

  • Your answer would be much improved by adding detail and removing commentary; one great part of your answer is your suggestion to remove the beans and cool them quickly on a sheet pan. Feel free to add detail around Mark's method in comment above, or link to "the 'remove vessel and shake' method suggested at Sweet Maria's" (which I don't see in their instructions at first glance). See the tour and How to Answer for more on our format. Welcome! – hoc_age Mar 3 '17 at 6:27
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This thing is not a workable solution to roast coffee all i end up with is Smokey tasting coffee beans. I was a packaging supervisor at a large coffee business packaging up to 15,000 pounds of coffee a day. I worked closely with the coffee roaster, and learned about coffee and roasting. a few years after leaving that business I made a bbq coffee roaster and it worked great. I have gone back to a bbq, and rotisserie, and a basket, and a box fan to cool the beans. All for under $200.00 and when I am not roasting coffee I can bbq food on it.

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After plugging the roaster in I raise the timer to 9.9. If you do consecutive roasts it will hold this time as long as you do not unplug the roaster. I fill the roaster with the appropriate amount of beans (weighed out if possible). I roast on low until the beans are getting lighter green and starting to swell a little (usually 1-2 minutes). During the roast I always tilt the roaster to let the beans on the side be mixed into the middle. I do this every 6-10 seconds and wear insulated gloves that you can hold onto it well. I slipped once and besides spilling the beans it broke my roasting chamber. I switch to medium until they are the color of desert camo (tan with some darker browns), That doesn't take much more than a minute. Switch to high and adjust fan as necessary to keep beans moving. Keeping it as low as possible will allow heat to build more quickly. First crack will start when the timer is down to 4 or 5 minutes left. You can reduce fan speed further to build heat more quickly and can increase it during tilts to aid in agitating the beans. If you don't hear second crack by near the end of the time it may be necessary to increase it 1 or 2 minutes. I usually roast to faint beginnings of second crack to a bit before and have always achieved spectacular results.

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I too have been roasting a few years with the Fresh Roast SR 500. I typically roast Kona or Ka'u coffees from the Island of Hawaii where I live. I use the default setting of a 5.9 minute overall roast time. The first 1.9 minutes are set on High and then to medium for the remaining 4.0 minutes. Once the Cool process stops, I remove the beans and place into mesh basket. With that approach, I am able to achieve a consistent, very satisfactory medium dark roast.

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