Latest Posts

  1. Podcast Episode 19: Kenya Coffee: Growing, Trading and Marketing

    Podcast Episode 19: Kenya Coffee: Growing, Trading and Marketing

    A while back we had Mary Maina Manyeki visit us in Oakland, and had a great conversation about her experiences as a Kenya coffee farmer.

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  2. The New Postcard

    The New Postcard

    We are really proud of our latest postcard because it captures an aspect of one of Tom's photographic projects; shooting realistic macro photos of coffee beans.

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  3. Sweet Maria's Green Coffee Sample Sets

    Sweet Maria's Green Coffee Sample Sets

    The ultimate order-ahead-of-time-pre-holiday-non-procrastinator-thing-you-can-buy-from-us-right-now

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  4. New Macro Videos

    New Macro Videos

    An inside look at parchment coffee and Kenyan coffee grades

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  5. Kenya Coffee Grades

    Kenya Coffee Grades

    A geeky macro video of the various grades and types of Kenya coffee. Some of this information can apply to wet processed coffee elsewhere too! -Tom

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  6. Sweet Maria's Product Guide: Roasted & Green Coffee Storage

    Sweet Maria's Product Guide: Roasted & Green Coffee Storage

    ...because you gotta put it somewhere.

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  7. Sumatra Aceh Mandheling Preparation Notes

    Sumatra Aceh Mandheling Preparation Notes

    Just some quick comments on the benefits to pre-sort this lot of Sumatra before roasting

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  8. The Amazing Spider Graphs

    The Amazing Spider Graphs

    ...fighting the crime of buying bad coffee

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  9. Adios! We're Out! Hooray!

    Adios! We're Out! Hooray!

    No more Centrals, and that's a good thing.

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  10. New Postcards...With a Lot of Information About Dry Processing

    New Postcards...With a Lot of Information About Dry Processing

    It's much more than just dehydration.

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  11. Roasted Coffee Macro Images

    Roasted Coffee Macro Images

    This photo gallery has a collection of extreme close ups of roasted coffee beans.

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  12. Podcast: Ferment in Colombia with Leo

    Podcast: Ferment in Colombia with Leo

    Breaking down coffee...literally

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Coffee Damage under UV Light

Coffee Damage under UV Light

Coffee Damage under UV Light, originally uploaded by sweetmarias.

Ultraviolet light is useful to see problems with coffee like mold and bacteria, but these are things that affect low grade lots that are already quite damaged. However, when I suspect drying problems with coffee, I check it out anyway. Some recent Sulawesi wet-hulled lots have been very surprising under UV light, and in general UV shows the problems with the wet-hull process overall (although our Blue Batak Sumatras fare well under UV light. This was a surprise. An Ecuador
Cariamanga lot with a nice cup, but some odd off notes cropping up way too often. The green coffee loots PERFECT. But under UV light, small nicks, little marks were I suspect the pulper scraped against the coffee seed due to misadjustment. Then in fermentation the damaged areas are in contact with mucilage and bacteria, rather than being protected by the parchment layer. The result is some off cups, but mysterious since there was little clue under normal light. I
could not get the coffee to "light up" completely under UV for the photo so the arrows assist in seeing the glowing areas, and then the 1 little pulper kiss marks can be seen.
--
-Tom

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