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Journal #3 - Three Batch Comparison

Recently I had to roast a coffee quickly to fill in the gaps on some orders. I had only grabbed 50lbs of it to hold me over so there was really no time to practice roasting it or anything, it was just purely toss it in there and wing it.

So I figured I would show the curves and what they tasted like.

The Coffee:

Nyamasheke Macuba - Macuba, Nyamasheke, Western Province, Rwanda

Coming from about 400 growers near the Macuba washing station.
Variety: Bourbon types
Process: Washed/Wet Process, Dried on raised beds
Screen size: 15-17
Density: .71

This is my number I got and it can vary between people taking it, the key is to use it only in your own context.

So first here are the three curves by themselves:

ligature roasting curves tanzania coffee
ligature roasting curves tanzania coffee

And then here are them stacked on each other so you can see the comparisons a little more:

ligature roasting curves tanzania coffee


So each batch was about 7.5kg. My roaster is 15kg so these were 50% of the roasters full capacity. Because of that you can see my charge temp was a little lower.

I tried a few different things but as you can see that roast differences werent that different. Just a slight increase in the first phase.

Now on to tasting:

For this I cupped 24hrs after roast. I broke the crust at 4mins and my first slurp was at 9mins. These are the base SCA standards, but I know there are other ways of doing it now a days. I generally would cup these a couple days afterwards as well to see the progression. Since these are really fresh, some flavors are going to be a bit more muted and there will be a certain level of dryness that is expected that will dull/disappear all together over the next couple days of resting.

Ground colors were all the same.

After grinding I evaluated the dry fragrance. These were all pretty similar in smell. No defects present. P915 had a bit more intensity in smell and also had a little more sweetness in the fragrance. Hint of dried cranberries. Wet aroma had the smell of milk chocolate.

P913 - Lemon, Raisin, Coffee Cherry, Chocolate. Slightly thin body, Cherry on the backend, acidity became more pronounced as it cooled.

P914 - Lemon, Raisin, Coffee Cherry, Chocolate. very similar to P913, cherry on the backend as well. drying on the end similar to cranberry juice. Best body.

P915 - More acidity. dark/maybe roast note on the backend when breaking crust. Better body than 913 but not as good as 914. Coming back to it after an additional 10 minutes, this one really had the best acidity. Pleasant and present throughout.

In the end, I would definitely take P915 and clean the curve up a bit. I would want to have better inner bean development in the first phase while still keeping it the longer overall roast time. Then keep the end temp and development the same.