Just back from SCAA and a post of findings and thoughts will follow.  This particular post is a bit overdue and takes precedence. I have posted about the Uber Grinder part of the Marco Uber Project a couple of times, initially where we wanted to explore the taste profiles resulting from different particle distributions and latterly about the results of trying to achieve the elusive ‘perfect’ burr.

I promised to post the grind profiles of the tests carried out. I will try to minimise the text and get straight to the plots. Everybody loves pictures! Note, all these experients were scientific analyses only – no taste comparisons were filed.

The first plot shows the Uber Grinder Burr for Marco, called type ‘M’ in the reports. The work continues to further refine this already excellent burr-set. Obvious commentary: the minimal amount of fines and height of the peak are the two key components we were after.

The next plot compares the ‘M’arco burr with a crushing burr. Interestingly, the profile is quite close to the M burr. With marginally more fines (not good) and a marginally higher peak (good), it gives the M a run for its money. While the general consensus was a crushing burr delivers a ‘worse’ particle shape than a standard burr, it was not verified on a taste test. The belief is the extra heat generated by the crushing burr and the inferior particle shape gave the ‘M’ the win. 

The next came the speed test, whereby the M was put through its paces at a standard 50Hz, 5Hz and 100Hz yielding 1420, 142 and 2840 revolutions per minute. The fastest speed delivered the worst plot, while the slowest speed, at 10% of standard matched the regular speed almost exactly. While grind temperatures were not measured, the slow output speed of the 142 rpm gave the win to the type ‘M’ but only just!

Challenge number three as the introduction of the accelerator or ‘turbo washer’. Designed to get the beans into the grinding teeth quicker, the resultant graph yielded an inferior peak. Fail.

Up stepped the glass pearls. Here we played with the ‘seasoning’ of blades, a process whereby the burrs are blasted with tiny glass beads to effectively blunt the burrs slightly to give the teeth a consistent output with no ‘scraggly’ bits, if you know what I mean. Unsurprisingly, the lesser the blasting the better the profile.