Roast Approach: India Kerehaklu Estate Blossom Cultured

Today's coffee that we are going to approach is a fresh crop (2025) from Kerehaklu Estate in India.  This coffee is a washed coffee with a blossom culture added during processing.

Arrival QC & Coffee Details

• Harvest date: March 2025

• Arrival date: August 2025

• Moisture content: 10.7%

• Density: 1.15 g/ml

• Altitude: 1025-1175 m.a.s.l.

• Cup score: 86

Initial QC Cupping:

Fragrance and aroma of dark chocolate, florals, and dark spices. Up front notes of milk chocolate and lavender with an aftertaste of lime zest and sweet maltiness. Medium citric and malic acidity with a heavy body and creamy mouthfeel. Overall well-balanced!

The Coffee:

At Kerehaklu Estate, Pranoy isolates local microbes and cultures them. This enables Pranoy to control which microbes are dominant during fermentation while still preserving the estate’s ecological fingerprint.This “blossom culture” is added to the coffee while it undergoes submerged fermentation for 36 hours. The Kerehaklu Estate is located within 250 acres of the Western Ghats, a 1600km mountain range in western India that has been recognized by UNESCO as a world heritage site for its biodiversity.

 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:

In this edition of Roast Approach, I will bring you four different roasts of this coffee.  Each roast providing a unique emphasis to the acidity, sweetness, body and balance of the coffee.  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 four 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.  This coffee entered in to first crack usually around 385.  Due to first crack being prone to some inconsistencies, I have adjusted all measurements of post crack development time to go from 385 degrees through the end of the roast.

The Approach:

Roast PR-18971 - "The Standard"

This particular roast profile is what I consider my "standard."  It's the base profile that I use on my first attempt at any coffee.  I start the coffee at a moderate charge temperature of 390, gradually increase the gas application up through caramelization, then gradually step down the gas application after first crack.  I also use a standard gradual increase in airflow, which you'll see echoed in all of my roast profiles.  This coffee ended at 402.6 degrees and a total roast time of 8:25 minutes.

When I roast this first "standard" my goal is really to observe the coffee and see how it is reacting to heat.  I am specifically looking at my rate of rise during Maillard and caramelization phases.  While I pay attention to first crack, I find that it can be an inconsistent metric.  What I am really watching for is how the coffee reacts to the drop in gas application and increase in airflow around first crack.  A plummet in my rate of rise around this time in the roast signals to me how much momentum I may need to achieve my goals in future roasts.  Lastly, I am watching for points at which the bean becomes exothermic and my rate of rise increases.  I make note of these temperatures so that I can adjust gas application in future roasts accordingly.

I was also able to take Agtron measurements of this set of coffees.  In measuring Agtron readings, it is important that they are all done at a consistent amount of time from the end of the roast.  For these coffees, I took readings approximately 14 hours off roast.  I also took readings of the external whole bean numbers and internal ground coffee numbers.  The "delta" number is the difference between the ground and whole bean numbers.  A higher delta can indicate that the exterior of the seed is developed (roasted) more than the internal seed.  In extreme cases, this may indicate scorching or burning on the exterior and underdeveloped flavors on the inside.  It can also create a very pleasant complexity with areas of the roasted seed that have undergone more sugar caramelization and other areas which may have retained more acids.  Where the delta is small, the interior and exterior of the seed have been developed to a consistent level.  This can result in a cup that tastes "baked" or "under developed", as there lacks the complexity between differing levels of development within the seed.

The Cup:

On the cupping table, this coffee had a fragrance of fresh blueberry, almond, and sweet pastry.  The aroma had notes of ripe pink berries, almond pastry cream, honey graham cracker, and coconut macaroons.  The body was smooth and creamy.  There was a cocoa powder finish that was a bit drying and bitter, possibly indicating that the coffee could use a cut back on development time.  For a first roast, this turned out really well.  

The Approach:

Roast PR-18972 - "Hot & Fast"

For this second roast, my goal was to see how the coffee responded to heavy gas application through both Maillard and caramelization phases.  An increase in gas application was started early (around 240 degrees) with full (100%) application by the start of early Maillard.  This 100% level of gas was maintained until right before first crack, at which point it was gradually stepped down.  The intense gas application created short periods in Maillard and caramelization, with drying being nearly the same.  With the increased heat also came increased momentum and a shortened period in post crack development time.  This coffee ended at 402.1 degrees and a total roast time of 7:43 minutes.

The Cup:

On the cupping table, the coffee had a sweet fragrance of citrus, orange blossom, and sweet coconut.  The aroma was full of orange, almond cookie, orange blossom and honey.  The cup had notes of dark chocolate, orange, and sweet butter cookie with a creamy medium-heavy body as it cooled.  The acidity was more juicy and vibrant on this roast of the coffee than the others.

The Approach:

Roast PR-18973 - "Fast Then Slow"

For the third roast, I wanted to try to stretch out the caramelization phase of the roast and develop more complexity in the sugars. I also wanted to keep the high gas application, with hopes of creating a coffee that was complex, sweet, and balanced.  To accomplish this goal, I used the same heavy gas application as in the previous roast, however I backed off the gas application substantially before the caramelization phase started.  You will see from my roasts that I frequently make the adjustments 10-15 degrees in advance of the start of the expected chemical reactions, so that at the beginning of those chemical reactions the roaster has adjusted to provide the energy catalyst that I am looking for.  Any time that I am looking to stretch out caramelization, i have to be mindful of my end temperature.  More time in caramelization can build mellanoidins and complex sweetness in the coffee, but it also means less momentum through post crack development.  If you try to achieve the same end temperature, you'll bake your coffee.  To adjust for this, I typically look at reducing my end temperature by about 2 degrees.  This coffee ended with a temperature of 400 degrees and a total roast time of 7:58 minutes.

The Cup:

On the cupping table, the coffee had a fragrance of coconut, orange zest and brown sugar.  The aroma was full of sweet caramel, bright orange and chocolate.  Flavor notes included juicy orange, hints of anise, chocolate, fresh ground nutmeg, and vanilla pastry cream.  The coffee was balanced with a smooth and creamy medium body.

The Approach:

Roast PR-18974 - "The Slow Snail"

For the final roast, I am looking to see how the coffee reacts with a slow trip through Maillard and caramelization.  For this roast, I also started with a lower start temperature of 380 degrees.  Additionally, I took the coffee to 402 degrees for an end temperature.  You'll notice that this coffee has the smallest delta between whole bean Agtron and ground Agtron numbers.  This would point to a more consistent development throughout the entirety of the bean, and thus less complexity.  This is typically how I would begin to approach a medium or dark roasted coffee where I was seeking to mute out some of the acidity and emphasize sugar browning sweetness.  This coffee finished at 402 degrees and an end time of 9:07 minutes.  

The Cup:

On the cupping table, the coffee had a fragrance of caramel, toasted coconut, and roasted marshmallow.  The aroma was reminiscent of rich pastries with notes of almond cookies, caramel and orange blossom.  Flavor notes were sweet caramel, butter cookies, orange, and butterscotch.  There was a medium body and creamy mouthfeel, with a lingering cocoa finish.  

The Takeaway:

For having never roasted an Indian coffee, this coffee was an absolute delight to roast.  It roasts easy like a washed central and is relatively forgiving in the cup as it leans into sugar sweetness.  I cupped this with numerous other roasters and each remarked that the coffee was exceptionally clean and reminded them of decadent pastries.  Pastry cream was a frequently mentioned tasting note.  With such exceptional sweetness and balance, this coffee would excel on espresso and as a base for milk beverages.  

My personal preference in the roasts was for the "Hot & Fast" roast.  On this coffee, the heavy heat application and quick sprint through Maillard and caramelization created the most complexity.  Pulling the juicy acidity out of this coffee was a bit more difficult than pulling out the sweetness.  The coffee leans towards sweetness.  An intense heat applicaiton really helped bring out the juicy citrus notes, while still maintaining the sugar development.  

Happy Roasting!