I would still use it. I used an old bag on a batch of IPA recently. Still turned out pretty clear. If you have an idea of what it smells like fresh, smell it again. Does it smell like Irish moss? That is what I did, and it sure smelled like Irish moss.
Primary: RIIS(For maple bourbon barrels) // CoconutLime IPA, // Partiglye from RIIS(semi coolship)
Secondary: Black Framboise(wild black raspberries) // Brett'n'Brown //Sour blonde // Sour brown // Brett porter
Barrel Aging:Sour stout(10 Gallon Rye Whiskey) // Blonde Peach Sour(10 Gallon Wine) // Sour Brown(5 Gallons) // BrettFunkBlonde(Gin/bourbon 8 Gallon)
In the Bottle: Downtown Julie Brown (Sour brown aged in gin barrels) // Peach saison // Concord wine
On Tap: Heady Clone