The other issue is that citric acid has a very distinct taste. It’s not really a dominant acid in grapes. The amount of lemon juice you would need to change the color would alter the flavor profile and make the wine more acidic.
We are going to start including additional Bentonite with the kits. Process will tweak a little bit more to mix Bentonite and carbon together first before adding the juice. This will help pull it out faster.
Again, to me, that is putting the ambulance at the bottom of the hill. I am suggesting finding a measure that would keep the wine from oxidizing, or "enzyme browning" if you prefer, at all.
Making a slurry out of the charcoal is more like what is done in Europe, and it is added slowly to the wine on a case-by-case basis. From what I have read, the addition of activated charcoal should be carefully calculated and performed and is not a "one size fits all" proposition. Lastly, I do not get the impression that it is
the way it is done in Europe and some US manufacturers, rather it is
a way to address a specific issue.
When I lived in Rochester, New York, I had some experience in commercial wine making at a local vineyard. They made a great deal of white wine and I never saw use of or heard mention of the use of charcoal. White grapes were picked, moved to the crusher/de-stemmer, pressed and piped directly into the fermentation vats.