“Coffee in styrofoam is against my religion.”  ~Betsy Cañas Garmon

The difference between your average cup o’ joe and the freshly roasted, ground, and brewed coffee you are about to see here is like night and day, black and white, right and wrong…you get the point.

Too often I hear people say things like, “I don’t like my coffee too strong, it tastes bitter” or “All coffee tastes the same to me.” Well, the truth is, over-extracting coffee grounds with too much water is more likely to give you a nasty, bitter taste. As for all brews being the same…well, I’ll give you that one. All bags and cans of coffee from the supermarket probably do taste the same. BAD.

My hope is that after reading this article, you will be equipped with the proper coffee knowledge and know-how so that you may never drink a bad cup again.

Alright, I’ll step down from my soap box so that we can get started. When it was recommended that I write this article, I was told it didn’t need to be too long. Unfortunately, I found it hard to express all of the necessary facts without it being a lengthy article. So my apologies, and I hope you find it all as interesting as I do!

Please note that this article pertains to home roasting in a modified popcorn popper. There are, in fact, many ways to roast coffee at home. If you want to learn more, Sweet Maria's has boat loads of information for you:


But do read on! There is a ton of great information to get you started right here. Not to mention roasting in a re-purposed popcorn popper is one of the most highly recommended methods.

Home roasting will require a moderate initial investment, but I found it to be well worth it! Plus, if you keep it up, you’ll make that money back and more in savings!

1. An old popcorn popper. It must have side vents, not bottom vents!

Sweet Maria’s lists a few models that are known to work well.


Not many new poppers come this way. You are most likely to find the right model at a garage sale, thrift store, or on Ebay. You can also buy an air roaster specially designed to roast coffee. They work much in the same way as a re-purposed popcorn popper, but tend to be more expensive and do not work as well.

2. IF you choose to modify your popper, see the website below for a list of materials and instructions. There are many ways you can modify a popper, however I feel as though this site is thorough in its directions and is easy to follow. A little Google searching and you’ll find a lot of other great ideas. Please exercise caution when working with electronics!


3. Some things you will probably already have in your kitchen: A metal colander, a wooden spoon (or second metal colander), a large bowl, a flashlight, and a container for storing the roasted beans.

4. And last but not least, the raw, green coffee beans! I could seriously write another 100 articles just on the variety of beans out there…but I won’t.

I personally buy my beans from Sweet Maria’s, although there are other places to buy them online that may have beans just as good. I have a personal affection for Sweet Maria's because they offer more beans than I can name from all around the world, along with a detailed description of each one. Their website has so much information on home roasting and coffee in general, I can’t even say I’ve read 1/3 of it. Also, they have a sampler pack which I found very helpful as a beginner.

Cost and Savings:

Before home roasting I was buying my favorite roasted coffee beans in the mail from a small roasting company states away. The beans were $14 per pound, plus shipping. Sweet Maria’s has beans starting from $4.80 per pound, almost a third the price! Not to mention green coffee beans will keep much longer than already roasted beans or coffee grounds (which are essentially stale right from the store).

Even at the supermarket, tubs of Folgers aside, the “better” bags of grinds start around $6 (and that’s usually the sale price). Needless to say, I find myself saving quite a bit in the long run for a cup of coffee that is so incredibly better in every way.
On to the Roasting! After all, that’s why you’re reading this, right?

The setup.

As you can see, my modifications are not the same as the website I mentioned above, and it’s much messier (my next project is to clean up this bad boy for ease of use).

I used a Router Speed Controller to adjust heat, and in addition to the dimmer switch, I added a 15 volt amplifier to the fan controls. The amplifier allows me to run the fan faster than the max speed it had originally.

Also, I don’t use an internal thermometer. Knowing when a roast is done is a test of your sight and smell. Most people rely more heavily on sight to start with, and learn the accompanying smells as they go. So be sure to use that flashlight to get a good look at the beans as they roast!

Measure out your beans. Today I am roasting Panama Carmen, a medium sized bean.

If you have chosen to modify your popper, you have a “Hands On” Roaster as you will be adjusting temperatures and fan speeds throughout the roast to maintain bean circulation.

An unmodified roaster is a “Hands ‘off’” roaster. Please do not misunderstand this to mean you won’t have to do anything, although roasting is a little simpler.

Amount of Beans to Use By Weight and Size
Bean Size
Hands On Roaster
Hands “Off” Roaster
Large (Nicaragua “Elephant Bean”)​
100-105 g​
110-115 g​
Medium (90% of beans)​
120-130 g​
125-135 g​
Small (Peaberries)​
130-135 g​
140-150 g​
Information courtesy of Michael Allen Smith from IneedCoffee.com

I roast in a West Bend Poppery I, which has a much larger capacity than the Poppery II. I think I actually ended up with about 137g of coffee for this batch, which you can see is higher than the recommended amount in the table above. Why use so much?

One big problem with air roasters is getting an even roast, where all the beans finish at the same level of “doneness”.  Beans come out uneven when they do not circulate properly when roasting. There are a few ways to address this, and bean weight is one of them.

The Spin Factor, here’s what you should look for:

When you first start, the beans should not be spinning round and round in fast circles. Instead, you want them to tumble and roll around as if you have a pot of water at a rolling boil. A little spin is fine, though.

A word of caution: The beans will expand in size as they heat up, so you don’t want to use so many beans that they are overflowing at the end of the roast. Just start with the recommended weight and learn as you go!

Pour in the beans, turn on the machine, and check their “spin factor”. Drop in a few more beans if needed.

NEVER WALK AWAY FROM THE POPPER DURING A ROAST. Roasts develop quickly, and if they go too far, they WILL cause a fire! Although, your roasts should never get anywhere near combustible stages.

I roast with the lid on, and place my large bowl below the mouth of the lid to collect chaff.

Chaff is the flaky outer skin that will come off the beans during the roast. If all the chaff does not come off the beans by the time you are done roasting, don’t worry. They do not add any flavor to the coffee.

The Overall Process

The green beans will turn a yellow color as they begin to roast.

I know this is a bad picture, but it clearly shows the beans at their yellow stage.

The beans will then darken to a brown color and reach “first crack” where you will hear a lot of popping and crackling.

Not too long after the first crack comes the second crack. If you prefer lighter roasts, you will never reach this stage.

When the bean is just about to reach your desired color, turn everything off and cool.

Cooling The Beans

Dump the beans into your metal colander and either stir with the spoon, or toss the beans between two colanders. When the beans feel warm to the touch, you can dump them into an appropriate container.

Leave them uncovered for 12 hours before covering with a lid as they need to release CO2. A container with a one-way valve is desirable for storage, however, I also use a plain glass jar for storing beans. If you use a see-through container like glass, you will need to keep it out of direct sun-light; in a cabinet is preferable.

Further Addressing Uneven Roasts

For the Hands-Off roaster:

Lighter roasts: 5-7 minutes. Darker roasts: 7-8 minutes.

For the first 30-45 seconds of the roast, leave the lid off, and use a long wooden spoon to stir the beans. When they start to turn yellow, you can put the lid on and let the popper do the rest. Use a long enough spoon so that you do not get burnt!

Please refer to Sweet Maria’s to learn the signs of roast doneness.

http://www.sweetmarias.com/airpop/airpopmethod.php - Page dedicated to hands-off popper roasting

http://www.sweetmarias.com/roasting-VisualGuideV2.php - Visual guide to roasting

For the Hands-On roaster:

Here comes the ultimate benefit of a hands-on roaster. I roast my beans in stages, so it takes a little longer than the hands-off method. It goes like this…

- Medium-low heat, high fan setting, until the beans are at their yellow stage. Maintain this temperature for 20 seconds to even out the roast. This extra time will ensure most beans are at the same stage.

- Medium-High heat until the beans finish first crack. You will have to adjust the air accordingly to maintain bean circulation.

- Cut the heat entirely, leaving the air on, and let the heat that already exists even out the roast for 20 -30 more seconds. This is a City+ roast; should you want a lighter roast, you can stop here.

- Turn the heat back on to high. Fan speed will probably be around medium-medium low. The rest of your roast will depend upon the roast level you are looking for. Please refer to Sweet Maria’s guide to learn the signs of each roast stage.


Extending the roast time with cooling stages will help to even out the roast, but please, DO NOT ROAST TOO LONG! What I mean to say is, if you extend the roast time too much, you will end up with a flat tasting coffee, bleck!

So, when you even up the color before and between cracks, only use as much time as is necessary for the beans to look more even. A slightly uneven roast will still be delicious; don’t ruin a batch because you wanted them to look perfect! You’re only trying to discourage a roast of blackened beans mixed with still yellow beans.

Label your roast with type and date

Depending upon the bean, you will need to let them rest for anywhere between 4 hours and 4 days before the bean reaches its peak. Decaf coffee, on the other hand, can be brewed immediately.

As a rule of thumb, you may brew your coffee the next day. I’ve only roasted one bean that required a 2-4 day rest and that was an Aged Sumatra from a 2007 crop.

Generally you should consume the beans within 5-7 days for maximum freshness.
Now I know this is a coffee roasting article, but I would probably lose sleep at night if I didn't share a bit about the brewing process...So here are my top tips and tricks for the best cup o' joe you'll ever drink!

1. Always use filtered water! Coffee is something like 90% water, so this is an easy way to make 90% of your drink that much better.

2. Buy a coffee grinder!

Coffee grinds don't stay fresh for very long. If you were going to invest in only ONE item to improve your coffee, I would absolutely recommend a home grinder. Burr grinders are better than blade grinders for a few reasons. I personally have a Cuisineart burr grinder which I bought at a reasonable price. For the savings, I missed out on some of the perfection in higher grinder models. No matter what you buy, though, having a home grinder and good quality beans is going to be the biggest difference in your coffee quality (in my opinion).

3. Invest in something other than your auto-drip.

You can buy a french press for pennies...OK maybe a $20 bill, but that's still an inexpensive kitchen item. You've got to try coffee outside of an auto-drip. The paper filter of an auto-drip sucks all the delicious oils that come naturally out of the bean. There are other choices besides the french press, but that's another article for another day.

4. Water to grinds ratio.

Like I said earlier, over-extraction of the beans is BAD. I haven't measured my water or grinds in ages, but just take my word on this one. If everything else is done right, adding more grinds will give you a more fulfilling coffee flavor without adding the "ick".

5. Water temperature.

Water that is too hot will simply burn the grinds, ruining the entire cup. The proper temperature is around 200F. This is something I have not measured in ages, either, though. If you are using a french press, just let the water come to a boil, let it sit for about 15-25 seconds, then pour over the grinds.


Do yourself one huge favor, never ever EVER wash anything that touches your coffee with soap! Not the coffee carafe, not the french press, and if you can handle the fact that just hot water and some scrubbing will clean your personal coffee mug sufficiently, not your mug either. I wish I could say I have a special stirring spoon that's never been washed with soap, but alas, I do not take it that far. So why no soap? Soap molecules can bind with the leftover coffee molecules, and who's ever asked for soap with two sugars? I'm sure there are other ways to do it, but good 'ole vinegar and water is how I keep my coffee equipment clean.
Well, if you've made it this far, I sincerely thank you for taking the time to read my article. May you never drink bad coffee again!