Not more than a few days or max 10 days. Why?
Once the fermentation is over, the yeast dies and settles at the bottom. This yeast then starts breaking down and releasing umami flavors (soy sauce). To counter this, professional brewers brew in conical fermenters. In a conical fermenter, you can remove the dead yeast, and hence the umami flavors from yeast breakdown will not bother you.
Homebrewers, on the other hand, periodically rake their wine and beer from primary to secondary to tertiary fermenters to get rid of the off-flavors from sediments.