There are many ways of profiling coffee, and differing reasons for doing so. Each roaster is likely protective of their own, but as a question we get asked a lot here, below are a couple that you may find useful.
I have never found sample roasters reflective of their (much) bigger cousins, so here are a couple of practical approaches I have used in the past for time and temp related approaches on larger roasters.
4 Point Profiling
The objective here is to repeat 4 roasts, each of a slightly different degree to cup. This should give you a range that you find your preferences lie, which can be further clarified by repetitions.
Pros
Will build great understanding of your roaster and the coffee.
Builds real confidence that your profile is correct.
Is more beneficial if setting up a roastery from scratch.
Cons
Uses four roasts of coffee
Can be expensive at larger-sized roasters.
Approach
It’s hard to give times and temps, as all roasters vary slightly so feel free to adapt this to your roaster. I’m imagining a 12kg roaster in this instance, which is probably as large as you want to go with this style, unless you have the budget to experiment.
You can stretch this experiment through second crack if you want, or alter the parameters to fit your usual spec and roaster set up.
So if you followed this, and preferred the dark but short roast, these could then be your next points.
Repeated sample profiling
On larger roasters, I found this to be useful. It does require a good amount of trier sampling and bit of kit but that can fairly easily be created if you don’t have it.
Here, we are doing one big roast, and choosing sample points towards the end. This will give us a great understanding of how the coffee is behaving during development, and where our production window is. Because it is just one roast, we know the turnaround and beginning development is the same.
Pros
Gives a level of comfort around progress of the coffee
Only takes one roast
Exactly matches the beginning part of the roast so reduces variability.
Works on big roasters too.
Cons
Can be fiddly to take samples, especially with certain brands of roaster.
Will make your curve look ugly
Requires equipment, and maybe a second person.
Samples need to be cooled quickly and efficiently
Approach
Roast a full batch of your coffee, but push it further than you would normally, without burning it. This will showcase the full stretch of coffee and may still yield you a usable batch.
If we are roasting 25kg to 215°C in 13 minutes, maybe aim for 220°C in 14 minutes, as an idea.
Sample enough for a cupping at 30 second intervals or set degree differences. Degrees can vary depending on probe settings, but generally not by much. Make sure the trier is replaced between samplings.
For time sampling then, based on 220°C at 14 minutes, I would take a sample at 12.30sec, 13 mins, 13.30 secs, and drop the batch at 14 minutes.
For temp sampling, I would sample at 210, 213.5, 217, and drop at 220.
Sampling is made hugely easier with a second person.
What I have often found with this, is that at least one result here will not be very good. This gives you a firm idea of the bottom or the top of your production window. One result will normally stand out clearer than the rest, and give you an idea of your real target -either time or temp of that sample with a small allowance either side. This should allow you to build your ideal roast profile, with finessing covered off during production.
Building your own mini cooler.
The piece of kit that makes the trier sampling process so much easier is a mini cooling tray set up. This is easily buildable yourself, but it definitely helps if you have a friend in the trades that can get you a discount. More recently, there are now some off the shelf solutions that may be useful for those that are not confident in DIY.
4 x 110 T junction drainage pipes (more if you want bigger!)
4 x size 4 mesh filters (Gold filters are ideal as all metal, but I have used the plastic framed ones fine)
1x 110 end cap
1 x 110 to 32mm waste adaptor (this may vary depending on vacuum cleaner)
Costing for profiling
Of course, profiling costs money, and with things being so tight these days, it’s good to discuss methods to manage the costs for this.
The easy one is to write this off as waste, but in some businesses could harm your KPI’s. You can also mark it as costs for development, and it will be more informative to look back over in future, but again that might not fit in your model.
My favourite for bigger batches is to roll the costs of profiling across the entire lot. For example, I buy 50 bags of Brazil at £6.50/kg and want to use 1 bag for profiling experiments. I take the cost for that bag (1 x 60kg x £6.50 = £390) and add that across the remaining 49bags.
So, if the entire lot cost £19,500 for 50 bags, and I split that cost across 49 bags instead, it brings the per kilo cost to £6.63 instead of £6.50. I can then use that as my base cost in my costing model, and don’t have to worry about losses in profiling. This does raise the baseline cost, and this may make the coffee less competitive on the market, particularly on smaller lots.
There are other approaches out there, and the open sharing of knowledge these days makes things so much easier, so please don’t think these are the only approaches to take. They are tried and tested though and might just work for you!