Espresso Knowledge Science
The start of information on the Osma for me
I used to be at Chromatic to style some coffees with Hiver, and I requested to gather some information. I’ve wished to look at if the Osma had any points with fines migration, so we grabbed some Brazilian espresso, and we pulled two pictures. By inspecting the particle distributions, I didn’t discover proof to recommend fines migration within the Osma.
I checked out a shot on the Osma and one on the First rate Espresso. I put the movies aspect by aspect. Each have some donuting, but when fines migrate, this could nonetheless come out in a lateral lower.
The Osma is a chilly (or scorching) espresso brewer that makes use of harmonics to shake the espresso and extract a really chilly brew espresso shot. The espresso hits in another way, and I think some solubles are extracted at completely different charges than in scorching espresso. I’ve been all in favour of learning this machine by amassing some information.
My concern with a few of different experiments, notably compelled fines migration, that the Osma might behave equally to compelled fines migration. I took a spent shot puck, and I lower it into three items.
Then I used imaging and pc imaginative and prescient to depend the particles. I did this for an everyday espresso shot with the identical espresso, identical grind (Versalab grinder) on the First rate Espresso machine. My preliminary measurements didn’t present a distinction, and I wasn’t positive if the samples have been dry sufficient, so I dried them for a day longer.
There wasn’t a lot shift, and I anticipated the underside layer to have a barely larger variety of finer particles, but it surely didn’t.
Then evaluating to the Osma, I discovered an analogous sample.
So to match the entire distributions, I took just a few measurements to take a look at the cumulative results. Once more, there was not an impact within the common or Osma pictures.
I zoomed into under 150 um in particle diameter, and the underside layer has the identical quantity of finer particles as the highest for Osma. The center layer appears to have barely extra, so it’s potential there was some migration from the highest to the center, however it’s exhausting to find out.
My first samples earlier than drying once more didn’t present a distinction, and for the primary pattern, I took further samples to confirm the measurement course of. For each, I took three samples, and for many, the variance was not massive.
