Roast Approach: Guatemala Acatenango Finca El Mirador Pacamara Natural

Today's coffee that we are going to approach is a fresh crop (2025) from Finca El Mirador in the Acatenango region of Guatemala. The farm sits at an elevation that ranges from 1500-1550 meters above sea level.  This is a natural processed pacamara coffee.  Pacamara is a hybrid between the Pacas and Margojipe varietals.  The beans are known for their large screen size, mostly in the range of 19-22 screensize.  Pacamara is known both for its seed size, as well as for being a very tricky coffee to roast.  If you talk to other roasters, you'll find an assortment of theories about how to roast pacamaras, and what you may expect to find in the cup.  We hope this exploration will help you to find new insight into how you approach this dynamic coffee.

Arrival QC:

The coffee arrived in October, 2025.  The coffee is natural processed with a range of screen sizes between 18-22, reflecting the large nature of the pacamara seeds.  The coffee has a normal moisture of 11% and a moderate density of 1.15 g/m. This is a very important piece of information.  Because of the large screen size, most roasters assume that the seeds are low density and require gentle treatment.  However, when analyzed, we can see that the seeds are of a moderate density that is inline with other specialty quality coffees from this region of Guatemala.

The sample roast was preformed on an Ikawa with the roast profile that can be found on our website.

The Roaster:

For these roasts, I'll be using a Proaster 1.5 kilo drum roaster hooked up to natural gas.  Batch size is 400g, approximately 35% of roaster capacity.  I've used a small batch size on this roaster to get closer to mimicking the gas power that you might find on a larger production roaster.  It must always be mentioned that each roaster is different.  The type of probe, placement of probe, and batch size will all influence the way in which bean probe temperatures are registered in a roaster.  With that said, don't read too much into the exact temperatures, but look more closely at the theory behind the approach, time spent in different development periods, and rate of rise to get a better idea of how to translate this profile over to your own machine. 

The Goal:

Typically in the Roast Approach I bring you three different roasts for the coffee, where each roast emphasizes a different overall heat application.  I started exploration of this coffee with my typical roast profiles and then played around with changing the charge temperature.  Changing the charge temperature can drastically change the overall momentum for a coffee roast, creating momentum that will shorten time spent in each phase.  

For this Roast Approach, you'll see a roast with a charge temperature of 380 degrees and a roast with a charge temperature of 405 degrees.  On the roaster I'm using, this represents a low charge temperature and a moderately high charge temperature.  

Hopefully this will provide you with the background you need to confidently approach this coffee in your own roasting adventures.

If you would like to learn more about my four phase approach to roast profiling, check out my “Roast Approach: Roast Strategy” blog.

Below is a comparison chart of the two roasts for you to follow along with. Each segment is measured in seconds with drying from charge through 305, Maillard from 305-350, caramelization from 350-first crack, and post crack development time measured from first crack through the end of the roast.  First crack occurred consistently on this coffee at 384 degrees.

The Approach: Roast 1 - Low Charge Temp

This roast began with a charge temperature of 380 degrees, which is moderately low for the machine I use.  The roast began with a low gas application of 50%.  The goal was to provide a slow, gentle temperature increase for the coffee.  With larger coffee beans, you have more plant matter to penetrate with heat.  When heat application is high, you can end up with more development on the exterior of the seed and an underdevelopment in the center of the bean.  The result of this type of roast is a cup that is both ashy/burnt and also sharply acidic.  You can observe this in a bean by breaking the seed open and seeing the difference in color between the outer and inner portions of the seed.

Early on, after turning point, I increased the heat application to 100% when the seeds reached a probe reading of 240 degrees.  I maintained this gas application through early Maillard, reducing gas application at 340 degrees as the coffee entered into the caramelization phase.  The intention with extending the caramelization phase was to increase the sweetness and build the body in the seed.  During this phase I reduced the gas application to 50%.  This provided enough continued momentum to finish the roast.  I did reduce the gas again to 30% at 390 degrees to finish the roast.  Looking back, this was not enough gas at the very end.  In hindsight, I would have maintained the gas at 50% to avoid a potential stall out at the very end.  The coffee ended at a temp of 400 with a roast time of 8:39.  The Agtron reading (on a Difluid analyzer) was 

Roasts don't always go exactly as you intend for them to.  In these moments, its important to remember that it's not what's on a graph or computer screen that matters.  What matters is what's in the cup.  I was concerned that the stall-out in the very last seconds of the roast may have negatively impacted the flavor, however I was very pleased with the final cup.

The coffee had an aroma of vanilla nougat, cherry, chocolate, and orange blossom.  The body was medium-heavy with a syrupy mouthfeel.  Tasting notes included cherry candies, chocolate, vanilla, green apple, and a tropical fruit finish.  Acidity was round citric acidity with notes of tangerine, and pink lemonade.

The Approach: Roast 2 - High Charge Temp

This roast began with a charge temperature of 405 degrees, which is moderately high for the machine I use.  In addition to the moderately high charge temperature, I utilized a fairly high gas application at onset of 75%.  This reduced drying time by 0:35 seconds and created significant momentum into Maillard.  This momentum built throughout the roast, shortening time spent in each of the phases.  

Gas application was increased to 100%  at 260 degrees.  It was clear with this coffee that there was a lot of momentum due to the higher start temperature.  With this much momentum, it was important to pull back the heat application before the caramelization phase.  If the coffee rushes through all of the phases too fast, it runs the risk of overdevelopment on the exterior of the coffee and underdevelopment on the interior.  

At 340 degrees, the gas was pulled back to 50%.  The coffee continued at a high rate of rise, so I pulled the gas application back multiple additional times through the end of the roast.  At 370 degrees it was pulled back to 40% and at 387 it was pulled back to 25%, where it remained through the end of the roast.  In all roasts of this coffee, the roast experienced a short spike in rate of rise after first crack, followed immediately with a reduction in rate of rise.  It's important to not instinctively reduce the heat at that RoR spike at first crack, or you will risk not having enough energy momentum to push through the RoR crash that happens right after the spike.  For this reason, I waited to adjust down my gas application until my RoR had recovered from the post-first crack crash out.  The coffee ended with a final roast temperature of 401.2 and a total roast time of 7:39.  Roast loss for this roast was 14.25% and the Agtron reading (on Difluid analyzer) was 101.5.  

On the cupping table, this coffee had a hard-candy sweetness and the aroma of cherry pie.  The medium body was silky, which combined with notes of vanilla to bring forward flavors of pastry cream.  Other prominent notes were peaches, honey, and hints of raspberry and chamomile in the finish.  The coffee had a tart pink lemonade acidity. On the undesirable side, my colleague found the coffee to have a bit of ashiness and there was some astringency on the finish.  These were likely due to some overdevelopment that may have happened on the exterior of the coffee with the high charge temperature.  While the coffee didn't show signs of scorching or tipping, it clearly had a bit of overdevelopment in the cup.

The Takeaway:

The goal with this roast approach was to see how these large seeds responded to heat application.  In the washed lot of this same coffee, the 405 degree charge temperature did not negatively impact the coffee with any notes of ash or unpleasantness.  However, this natural processed coffee was clearly more susceptible to the high heat. Also, I would mention that I feel that this natural processed lot of pacamara benefited more from the lower charge temperature and longer drying time.  

Another interesting thing about roasting this coffee was the high roast loss, while maintaining a relatively high Agtron color reading.  Typically, a roast loss over 14% on my roaster would result in a coffee that has significant sugar browning characteristics and start venturing into the medium-dark realm.  I'd expect to see a corresponding Agtron reading of around 79 or 75 with a coffee that has this type of roast loss.  With both the washed and natural processed coffees, I saw a high amount of roast loss but a very light in color coffee.