Dialing cold brew for a class

I’m outlining a short workshop for new baristas on cold brew extraction and could use input on pacing. Plan is to run side-by-side brews — 1:6 at 800 microns for 14 hours vs 1:8 at 1000 microns for 18 hours — then measure TDS and taste for clarity vs body; in a 60-minute slot, would you prioritize grind calibration, agitation control, or refractometer basics?

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But i’d prioritize refractometer basics — calibrate with distilled water, then measure both; quick 5‑minute “800µm vs 1000µm” sieve check if time allows.

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