My second year making wine.
I have this grayish-purple stuff in the neck of my carboys. It appears to have risen from the wine, sliding up the top of the carboy and collected at the neck. Not seeing anything else weird in the wine.
I crushed 6 crates of California Cabernet Sauvignon and one crate California Merlot. Fermentation seemed to go great, I pressed after nine days when brix was at -.5* and moved to four 5-gallon carboys.
After ten days I racked into fresh 5-gallon carboys and added 2.5tsp K-Sorbate and 1.5gm K-Meta to each carboy. I topped each with some tap water to bring the level up to the necks. The wine smelled and tasted fine.
After about a week I saw this. It does not seem to have gotten any more significant/any more amount.
Does it look like something to be concerned about? If so, any suggestions? Any comments on my process so far?