An interesting alternative to PVPP, for its prevention/cure of wine browning, is to use the ‘Black Wine’ technique on whites, esp Chardonnay.
With Black Wine, once the grape clusters are pressed, you expose the juice/must to as much air (oxygen) as possible (or desired). The oxygen oxidizes the ‘easily oxidizable compounds’ in wine (the same oxidizable compounds that pvpp removes). Since these compounds are oxidized in an aqueous/water solution, the oxidized compound won’t be soluble in an alcohol solution (eg wine) and will drop out of solution once fermentation is complete. If these compounds are oxidized in an alcohol solution (aka wine), then they remain soluble and remain in the wine.
The large amount of sugar in the must prevents compounds other than the ‘easily oxidizable’ ones from being affected.
I remember visiting Matanzas Creek circa 1990 and being shown the muddy, brown must in their chardonnay tanks. They explained that they were letting it oxidize. I think Dave Ramey was the winemaker there then.
There are some attempts to do this with red wines. Various agents can be added to the tank to modify or bind proteins and cell wall pectins to help improve extraction from the skins. This is fining in a sense because these bound components will end up being removed from the wine during later racking.