Infected bottles?

[gwoods22]

I brewed an IPA (attempted recipe here) a month ago and a few of the bottles appear to be infected. My efficiency wasn’t great so my OG was 1.069 and it finished at 1.019 but I don’t believe that’s much of a factor here. The first photo is of a sample on bottling day (bright pale colour) and the second is a bottle from last night (much darker). I think the bottles may be infected they had an unfavourable slightly sour character, maybe even a little Brett (I’m not a huge fan of Brett personally). Should also note, aroma was excellent due to a healthy dry-hop and carbonation was also good but the taste was quite bad.

I tried using Cooper’s carb drops for the first time in this recipe to prevent the need for a bottling bucket and ideally limit oxygen exposure. I gave the bottles a PBW soak then a thorough rinse and sanitize using one of those jet bottle washers full of star san. However I didn’t use gloves when adding the carb drops, I just put one in each bottle with my bare hands. I had read that the alcohol content greatly reduces the infection risk during bottling so I didn’t think much of it. It also appears some bottles are much paler/brighter than others so I’m going to try one of the pale ones tomorrow to see if it is any better. Any idea what may have happened?

 

[JohnSand]

I tend to think that color change is an indication of oxidized beer, especially an IPA.
I wash my hands carefully, and even spray sanitizer on them. But I doubt you would infect your beer by bottle priming. Sugar doesn't spoil, and doesn't support spoil organisms. Your carb drops are not the suspect here.
Keep us posted.

 

[jdauria]

I agree with John, that the color change is most likely oxidation. IPAs and especially NEIPAs are highly vunerable to oxidation. I am assuming you open transferred from a fermenter to bottling bucket, then bottled from that. So that's a lot of oxygen getting in. Oxidation can be described as a combination of stale, winy/vinous, cardboard, papery, or sherry-like aromas and flavors. Your slightly sour description could be that winy/vinous or sherry like flavors.

 

[Hans O. Lowe]

I am assuming you open transferred from a fermenter to bottling bucket, then bottled from that. So that's a lot of oxygen getting in.

And more during the "Healthy dry hop"

 

[gwoods22]

I think that winy/sherry flavour is a better descriptor than sour so it makes sense oxidation was the culprit. I'm glad it doesn't appear to be a sanitation issue! It's funny to me that this never happened in my first 4 brews but this was definitely a more susceptible recipe, 70% 2 row to 30% oats, 60 IBU with a whirlpool and dry hop.

@Hans O. Lowe I did actually do an oxygen-free dry hop by using food safe magnets to attach a mesh bag full of hops to the lid of my fermentor. Then after fermentation finished I pulled off the top magnet to release the hops!

I don't have CO2 to purge my bottles but anything else I could try to help limit oxygen exposure when bottling?

 

[BasementArtie]

I think that winy/sherry flavour is a better descriptor than sour so it makes sense oxidation was the culprit. I'm glad it doesn't appear to be a sanitation issue! It's funny to me that this never happened in my first 4 brews but this was definitely a more susceptible recipe, 70% 2 row to 30% oats, 60 IBU with a whirlpool and dry hop.

@Hans O. Lowe I did actually do an oxygen-free dry hop by using food safe magnets to attach a mesh bag full of hops to the lid of my fermentor. Then after fermentation finished I pulled off the top magnet to release the hops!

I don't have CO2 to purge my bottles but anything else I could try to help limit oxygen exposure when bottling?

Fill the bottles really high. Maybe use a solution of SMB you can pipette in each bottle.