High Altitude Roasting

I’m interested in hearing from other higher elevation roasters. I live above 5000 ft and first crack for me is around 194 C. Most roasts from others have first crack above 200 C. Here is my latest profile of a Costa Rica Tarrazu medium roast that has a good balance of sweetness, acidity and slight bitterness.

This is very interesting. I went to your RW page to look at the details of that particular roast. Your batch was about 1 lb (1/2 kg). I wouldn’t say your FC is terribly far off from most of us at sea level. Remember at higher altitude there is less air pressure and less moisture in the air, therefore you’re probably going to lose the moisture from the beans earlier which might explain your FC at a lower temp. Maybe consider some of the principles used for high altitude baking and cooking adjustments: Baking and Cooking at High Altitudes - BettyCrocker.com - it also mentions that gases expands faster.

I’ve never cooked/baked in high altitude so I can’t help beyond some conjecture based on science of cooking/baking that is well documented :slight_smile:

That said I also noticed you used F5 all the way in that roast…I think you might be drawing out too much of the hot air from the drum at F5. When I roast 1 lb, I start with F2 and only towards the very end I might go as high as F5 to draw out the chaff.

I lived in Albuquerque, NM for many years. Albuquerque is over 5000 feet above sea level.

Water boils about 12 degrees C cooler at 5,000 feet. so your first crack sounds about right. the water in the beans will create steam at a lower temperature and therefore start cracking at a lower temperature. The down side to this is that: you should need more heat to get to the same roast level that we do at sea level.

There is a canning company in northern California that reduces it’s tomato sauce under vacuum. by doing so, the tomato sauce is not getting asmuch heat and the sauce does not get caramalized or have a maillard reaction. The process still creates steam but at a lower temperature. (BTW a pressure cooker works on the opposite principal: it cooks things faster because it is under pressure)

Hmmm, this is an interesting mental exercise. What role does the remaining moisture left in the beans have on the final roast temperature?

My initial reaction would be that if you are timing your development from the start of first crack and the temperature is lower, you might want to try dropping at a higher temperature.

But, as always: What your get in your cup that you like is the best solution.

I like the flavor of this roast. I have done darker roasts and those are good too. If I’m looking at another roast profile I would like to know where and what altitude it was done before I try to duplicate it. Some say that roasting at higher elevations produces a better cup of coffee
High Altitude Coffee Roasting: Why It's Better

Is there a way to modify shared roasts to display in Fahrenheit?

Roasting in higher elevation situations is complex, because some of the roasting involves water, and some reactions don’t so much. I think the drying phase is more altitude dependent, so mess around with that. You’ll read a ton of varying opinons about altitude, but go with what tastes right.

Drying phase has the most water, however it is possibly the least flavor influencing. But if you evaporate ate a different speed from sea level, then that will effect the rest of the roast, no?

Getting into maillard and caramelization (browning), you still have water involed. Pretty much until first crack.

Be super consistent with how you mark your color changes. get a good accurate LED for monitoring color during the roast. Buy an LED light for cinema and television. They often have adjustable color temp and much higher color accuracy. This can help a lot. Once you find the average temp for certain color stages, you can sort of cross reference temps to your calling color changes, and further make your stage marking more consistent.

THe average times for roasting are 4.5minutes for drying, and 4.5minutes for maillard into First Crack(FC) at about 9minutes. Some people extend those times byu 30 second here or there and get 10minute FC, and other may shorten those times and get 8minute FC.

So go through the steps and start analyzing your roasts:

  • Low and slow dry and back up to standrd time for mailllard
  • fast thru drying and back to standard for mailllard
  • standard for drying and slow for maillard
  • standard for drying and fast for maillard

You can further break things up into mailllard vs caramelization
If maillard is starting at Bean Temp 260F, or there abouts (green to yellow), and caremalizarion somewhere further into the yellow to browning stage, then you can mess around with speed in the maillard phase and slowing in the caremlixzaion… Or flip that. Or make a dip in between vs a straight constant RoR. They all effect the flavor, but idk which is prefered to you.

Then repeat this every time your room temp changes more than 5 degrees. as you may need to extend the drying phase in colder rooms to more evenly warm up the bean.