In his book "The Complete Joy of Homebrewing", Charlie Papazian tells us to add gelatin to the beer just before bottling, at the same time we add priming sugar. (to clarify the beer)
I haven't heard anyone else add gelatin this way. It seems that the consensus is to add gelatin at an earlier stage, particularly right after a cold crash.
Is there any disadvantage to adding gelatin at this late stage?
The only advantage I can think of is that it resolves two issues at the same time if you add the gelatin with the priming sugar.
However, this shortcut will also result in more sediment in the bottom of every bottle.
I definitely think it is advantageous to add the gelatin ahead of time, give the haze a chance to settle out for at least a few days, then bottle after that.
I've used a product called a Beer Fining, which looking at the ingredients was just gelatine. That suggested to mix with some warm water and add to Beer about 24 hours before bottling. This sounds better to me as it eliminates the only downside as the sediment it does settle out will be left in the fermenter rather than in the bottles.
So it seems that this is a common process without any downsides other than the sediment it creates.
