Looking for opinions. I know we all go to great lengths to keep oxygen exposure to a minimum on finished beer. We rack gently, flood the kegs with CO2 to purge O2 out, and make sure that dry-hopping doesn't introduce unwanted O2. We also try to minimize O2 exposure during recirculation, although HSA might not even be an issue. We've been told to "not fear the foam". But I get a lot of foam when I am sanitizing my kegs. That foam contains air bubbles which are full of O2. I'm racking on top of this foam. Just wondering......