Tuna or Fish Odor in Roast?

Discuss roast levels and profiles for espresso, equipment for roasting coffee.
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Boldjava
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Joined: 16 years ago

#1: Post by Boldjava »

keno wrote:Interesting, I just roasted some Kenyan coffee two days ago, not this one but some Makwa AB and noticed exactly this bad tuna-like aroma post roast. Not exactly a taste I want to experience in my coffee, but fortunately it doesn't really come through in the aroma once ground or in the cup...
Kenya Gakui Peaberry

Yesterday, two PhD students, Food and Science Dept at the ag school cupped with us, working at improving their cupping skills. The tuna/fish odor topic in roasted coffee came up. Both majored in organic chemistry as undergrads.

They immediately said, "Oh, that is just amine degradation. It happens in foods."

They went on to explain the chemistry involved that was way, way, over my head. But, at least now when I pooch a roast and Charley the Tuna appears, I can sound smart and say, "Oh, that is merely amine degradation" and quickly change the subject before anyone has a chance to ask me to explain it.

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LMWDP #339

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jbviau
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#2: Post by jbviau »

Dave, I remember talking about this with you before. Enjoyed the post. This is definitely something I've experienced, though usually with pre-ground coffees roasted darker than I'd prefer.
"It's not anecdotal evidence, it's artisanal data." -Matt Yglesias

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Boldjava (original poster)
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#3: Post by Boldjava (original poster) »

I have gotten in natural Ethiopians and believe in my situations, it was when I applied heat too quickly.
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keno
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#4: Post by keno »

Boldjava wrote:Yesterday, two PhD students, Food and Science Dept at the ag school cupped with us, working at improving their cupping skills. The tuna/fish odor topic in roasted coffee came up. Both majored in organic chemistry as undergrads.

They immediately said, "Oh, that is just amine degradation. It happens in foods."

They went on to explain the chemistry involved that was way, way, over my head. But, at least now when I pooch a roast and Charley the Tuna appears, I can sound smart and say, "Oh, that is merely amine degradation" and quickly change the subject before anyone has a chance to ask me to explain it.
Thanks for following up on this. Very interesting. Now I'm down with amine degradation! :)