Work Log
23 Jun 2020
Just received a new shipment of green coffee from Sweet Maria’s. I decided to try another test.
09 Aug 2019
My friend Erin and I tested a couple of the fermented beans with interesting results. The 48hr CO2 batch resulted in a spicy brew. I mean really spicy. The 24hr diH2O did not however. This warrants further investigation.
Apparently there is a startup, afineur, which specializes in fermented coffee beans. They sell them for $50/lb. Their goal seems to be reducing acidity and bitterness, not emphasizing flavors. I bet there is a market here…
29 Jul 2019
Finally dried the “48-hour” beans. They have been in the fridge since the actual 48-hour mark.
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25 Jul 2019
The beans in the dehydrator are “done”. They were removed and placed in labeled, plastic bags. Without proper water content testing I can’t really be sure. I don’t think it matters, however, since the beans are destined to be completely dehydrated and burned during roasting.
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The 48-hour fermentation beans are starting to smell off. This may be too long for room temperature fermentation. Neither jar smells better than the other, so I do not think the acidic environment helped.
24 Jul 2019
I poured about half of each jar into a sieve to drain, then put them in my dehydrator. The temperature is about 40C. I picked out all the seeds which had “sprouted”. Oddly enough, the carbonic acid jar batch (left) had roughly twice the number of sprouts. Weird.
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Anyway, ten of each of the best looking seeds were placed in a 50:50 verm:coir potting mix. After completing one of the pots I realized that the sprout could actually be a stem, not a root. So one entire pot is planted with the sprout facing down and the other pot is a 50:50 mix of up/down. Both pots were put on my plant shelf alongside the other pot of coffee seeds planted about a week ago.
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23 Jul 2019
Added 200g of green coffee to a 1qt mason jar and filled half-again with club soda (carbonic acid)1 at about 8pm. Added a second trial of the same except used deionized water. I will “ferment” these beans for at least 24 hours before drying them. Perhaps I will split the trials into 24 and 48 hour samples. I could also try some longer fermentation times in the refrigerator.
22 Jul 2019
The beans in the dehydrator have lost approximately 41g (down to 259g total). I roasted these and still had substantially the same problem of varied colors. I also noticed that even the “green” roasted beans were thoroughly roasted and could break easily. Perhaps the original beans were fermented differently? I could try to ferment them again, although it wouldn’t be as effective without the mucilaginous layer of the whole coffee cherry.
I should take some samples and determine the actually water content the right way.
19 Jul 2019
A few weeks ago on my Guatemala trip, I acquired 10lbs of green coffee beans (for $16 hehe) at a street market in Santa Cruz del Quiche. Upon first roasting, the coffee had wide variations in color. Many beans were still green looking while others were full dark roast. I do not like dark roast so this batch was not very pleasant. My first thought was that they were unevenly dried. So I set 200g in my dehydrator at around 35C.
18 July 2019
Previously I attempted to use sonication to make coffee. The results were promising, but I never followed up.
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Bibliography
This idea came from the process called carbonic maceration.↩