No, fortunately! With the process I follow in my brewing, the beer doesn't come into any significant contact with O2 after intially pitching yeast. After that point, the only time it's really possible is when I remove the carboy hood to transfer (or, in this case, to quickly add the simple syrup and then the yeast later on). Still, the yeast was producing CO2 during the entire time, so there would still have been a bit of a 'blanket' of that gas over the beer...and then rousing kicked up more CO2 and would have blown off the small amount of O2 that could have been introduced while the carboys were open. By pressure transferring the beers into sanitized kegs afterwards, there wasn't any further opportunity for O2 pickup. As I said in the video, the beer did taste more aged than I prefer my Kölsch (with the yeast character being more muted than it would have been otherwise), as I normally would have been drinking it for a few weeks by the time this batch finished up. I usually try to share and/or drink through that style fairly quickly after getting on tap. That's my theory, anyway. I'm pretty confident about it, as I've had a few stalled fermentations over the last 14 years (once with a Wyeast Belgian Saison strain and once with their European Ale strain), and the extra yeast trick worked. This time, I was hoping that the sugar dosing would be enough. Haha...it wasn't, but at least I know to not bother with that in the future. Hope that helps! :)
You don't get any off flavors from oxidizing the beer during the stalled fermentation?
No, fortunately! With the process I follow in my brewing, the beer doesn't come into any significant contact with O2 after intially pitching yeast. After that point, the only time it's really possible is when I remove the carboy hood to transfer (or, in this case, to quickly add the simple syrup and then the yeast later on). Still, the yeast was producing CO2 during the entire time, so there would still have been a bit of a 'blanket' of that gas over the beer...and then rousing kicked up more CO2 and would have blown off the small amount of O2 that could have been introduced while the carboys were open. By pressure transferring the beers into sanitized kegs afterwards, there wasn't any further opportunity for O2 pickup.
As I said in the video, the beer did taste more aged than I prefer my Kölsch (with the yeast character being more muted than it would have been otherwise), as I normally would have been drinking it for a few weeks by the time this batch finished up. I usually try to share and/or drink through that style fairly quickly after getting on tap.
That's my theory, anyway. I'm pretty confident about it, as I've had a few stalled fermentations over the last 14 years (once with a Wyeast Belgian Saison strain and once with their European Ale strain), and the extra yeast trick worked. This time, I was hoping that the sugar dosing would be enough. Haha...it wasn't, but at least I know to not bother with that in the future. Hope that helps! :)