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White Crystals After Crushing
Jim Shurts — Richland, Washington asks,
Circumstances caused me to pick my Merlot grapes earlier than desired (Brix=21.2, pH=3.61, TA=5.1) this past harvest. After processing them through my crusher/de-stemmer and cleaning up, I noticed a white residue/deposit on the inside surfaces of the equipment and in the catch vessel. I rinsed the equipment just after finishing, so it was not dried on, rather deposited during processing. It does not come off easily by rubbing with a finger, but scrubs off fairly easily with a scrub pad. I did not remember it from last year. Any ideas as to what it is? Many thanks.