MARGINAL GAINS - DO REGION OR PROCESS HAVE AN IMPACT ON YOUR EXTRACTION %?

Alright, this is a quick hit so buckle up.

The question was asked of me this week, are natural processed coffees more soluable than washed? They asked because we have a stack of data on espresso extraction, which to our detriment we've done bugger all with!

So, I set about some basic analysis, but first some context;

• extraction % is measured as Optimal extraction, as discussed here.

• This is measured after dial in and used as feedback data and a fallback if all goes tits up.

• We use a VST Lab Coffee III refractometer with filters.

• The data covers two small equipment changes, we switched to the Pergtamp, and recently to 15g VST baskest (from 18g).

Here's the data , click me. 

Although it is by no means rigorous, the sample is large enough that I think we can see some interesting results.

• We've used 105 espressos this year! ( we have 1 set of duplicate readings)

• We've used 24 roasters so far in 2015 ( bit of a surprise)

• Our average % is above 21%, which is pretty good for a non-EK setup.

• There appears to be no significant difference in ext% due to Process, Region, Time from Roast or Roaster.

fin.