My wine preserver came from Amazon today. Haven't used it yet, and as SRJHops says, how will we know if it works?
I'll give it a try soon and report back, though my guess is unless I do get oxidation, it will be hard to PROVE it worked --
Sorry I'm a bit late to the party here, but...I stumbled on this thread and wanted to share my still limited experience with this wine preserver.
I also experimented a bit with it and quickly found out that it isn't a very practical option if you want to purge
everything with it, meaning fermener headspace at dry hopping, bottling bucket, and all bottles as well as the bottle headspaces. I don't know what your experiences have been here (would be interested to hear them), but on the first batch I used it, I managed to empty a can and I couldn't even purge all my bottles/headspaces (approx. 7 gal batch size).
For such "large-scale" purging activities, I believe a proper CO2 tank is the only way to go, economically speaking.
I'm actually still using the wine preserver, but I limited myself to only purging the bottle headspaces for my bottle conditioned hoppier beers, since I found this part of the process to have the biggest impact overall.
For that, it works really well and you don't need as much gas. I think you need some kind of bottles that allow you to seal them immediately after the purge, such as flip-top bottles. Not sure it would work just as good when using crown caps and a bottle capper.
I agree it's difficult to prove its effectiveness at dry hopping, since you would need at a minimum to perform a split batch in two different fermenters...and even then...
On the other hand it was very easy to prove its effectiveness in the bottling phase. Just purge the headspace of a few bottles, and do not purge some others. Then do some side-by-side compares over a given timeframe and see the difference. In my case it was striking, at least color-wise.
On the other hand, purging the bottles prior to filling did not have any impact whatsoever, neither on color nor on taste/aroma.
By the same logic I concluded that it would not help much to use it for purging fermenters or bottling buckets during the transfer.