Roasting Coffee at home: Can anyone do it?

In theory, it makes economic sense to roast your coffee. In theory, you could save a lot of money and have the freshest coffee possible; however, is it practical and is it worth to do it?Let's get our hands dirty and roast some coffee!

In my previous post, we got to the conclusion that investing on a coffee roaster could pay for itself within the first year. To test this, I bought a Fresh Roast Coffee Roaster SR500 and plenty of green coffee beans from Sweet Maria's.


For me, it would be worth it to roast my beans if, in addition to the cost savings, I could reliably produce good coffee, with no waste, and I could make enough for two weeks in less than 30 minutes.

Initial Investment

At $200, buying the Air Roasting Starter Kit was no brainer because it turned out to be a lot cheaper than buying things separately. With the kit I received:
  • The Hot Air Roaster: Fresh Roast SR500 
  • 8 Lbs Green Coffee Sampler 
  • 10 valve bags for storing 
  • 1 Roast Log 

Let's forget about the bags and the roast log; getting the roaster and the green beans by $200 was a great deal, considering that buying the roaster by itself is $179. At this price, I just bought 8Lbs of coffee at only $21, or $2.625 per pound



In my previous post, Does it makes sense to roast your coffee, we established that the average pound of green coffee beans was ~$7 if you buy individual bags. With this sampler, each ounce of green coffee is $0.164, which is 11.6 times cheaper than buying roasted coffee!!!

By purchasing the sampler, you lose the ability to select particular coffee beans, but we are just getting started, at this point we don't even know what coffee beans we want. 

The roaster is super simple, setting it up and reading the instructions is a matter of a couple of minutes. We are ready for our first batch.

First Batch

For the first trials, I am using Ethiopian green beans, which are supposed to be good for espresso.

Since I was afraid of burning the beans or creating a lot of smoke inside the house, I did this batch in the patio. I don't think this is required, but to avoid the smell inside of the house, I will continue doing it this way. The hot air roaster is small and portable.

I followed the instructions on the tips sheet included by Sweet Maria's and used less green beans than what the instructions manual indicated (two scoops of green beans instead of four). I know I don't like very dark roasts; I prefer medium roasts which are sweeter and less bitter. On
 my first batch, my primary concern was not to burn the beans and end up with waste and lots of smoke. Therefore, I was very conservative with the times and heat.


Ready to start the First batch

Based on what I read, I set up my timer for 7 minutes. Unfortunately, I was too excited to see the results, and I interrupted the cooling cycle by mistake( I didn't know there was a cooling cycle). The final result was a very light roast, with beans that didn't increase much in size, and with a lot of chaff left on them.


Color

I believe that I should have waited longer, the color of the beans seemed to be on the light side. I also expected them to grow more in size, but they were almost the same size as the green beans, which tells me they probably didn't go through what they call "The second crack".


Batch Size

I was disappointed by the final amount of coffee, it was not even enough for one day at our home, it was over after two double and one single shot (3 Shots). I believe I can increase the batch size a little more, but I don't think I will be able to make enough coffee for one week on a single roast. With this type of roaster, if you make the batch too big, the air will not be able to move the coffee around, and it will burn some beans (continue reading since I tried this).


Taste

Although it tasted good, it was too mild. We prepared a couple of lattes and the coffee flavor almost got lost. I believe I can correct this by roasting it a little bit more.


Second Batch

This time, I added one extra scoop of green beans for a total of 3 to try to get enough coffee for at least a couple of days. I also waited 1 minute longer (8 minutes) while roasting and let it run its 3-minute cooling cycle.


Color

The coffee beans look darker than the first batch, but they are still within the parameters I like; however, there is a notorious increase in the size of the bean. I believe this is due to "The second crack," which it didn't happen on my first batch.
From left to right: Green Beans -> First Batch -> Second Batch

Batch Size

Since this time the beans increased in size, the extra spoon of green beans is more notorious, and the batch is considerably bigger; However, it only lasted three days (around eight shots of coffee). On the 4th day, I was almost tempted to go out and buy some roasted beans.


Taste

The coffee is stronger, still sweet, but even in a latte, you can taste it.


Third Batch

It was midweek, and I was out of coffee, this was a disaster! I had to roast some more. This time, I used the amount recommended on the manual, but not on Sweet Maria's tips sheet, which is four scoops. The batch obviously was bigger, and it gave me a total of twelve shots, which should be enough for four to five days (almost a week).

However, the roasting was inconsistent. Since there's a greater amount of coffee, the hot air (which was set to max) is not able to adequately move the coffee around, and some of the beans got burnt while others were not roasted enough. Fortunately, it was only a minor portion of the beans, most of the batch was acceptable. There are ways you can control this by manually moving the beans or playing with the cooling cycles; however, I want an automated process, and I'll reduce the batch size next time.

Too many beans could produce inconsistent roasting: These come from the same batch

Preliminary Conclusions


After these initial batches, I believe anyone can roast coffee at home; however, it is too early to reach a conclusion on whether it is worth it. The roasting process is very smooth. I was initially afraid of burning the beans, but you can easily control it if you are paying attention.

Quality wise, once I find the right settings I am pretty sure I will be able to make consistent good batches, comparable to some of the best ones I can buy, but at a 10th of the cost. 

My primary concern is the batch size. Their documentation indicates it should give enough for 20 cups, but they might be talking about very light brewed coffee. For espressos, I don't think I will be able to get more than 12 single shots or 6 double shots in one batch; however, the total process takes around 11 minutes per batch, it takes me more time to go to the store and buy roasted coffee. I believe that making a couple of batches over one weekend should give me enough for two weeks, but we will see...