What the hell is causing this purple ring in my krausen

[Jj8564]

I have had this happen in most of my brews since I started using stainless steel I do a hot soak with pbw and then Sanitize with star san I don’t think it’s producing off flavors but i don’t think it’s normal

 

[Pennine]

How many times have you used that fermenter? I always noticed a dark purple ring the first few times using a new SS fermenter even after cleaning.

 

[Jj8564]

One of the pictures is from a brand new spike flex the other is from an anvil brew bucket that I’ve used at least five times now

 

[Pennine]

One of the pictures is from a brand new spike flex the other is from an anvil brew bucket that I’ve used at least five times now

I am not sure what it is, but yeah that seems like what happens to me, with my anvil buckets 5 times seems right it was worse than with my SS brew buckets.

 

[Pennine]

I think it's likely left over grease on them from manufacturing?

 

[Jj8564]

I think it's likely left over grease on them from manufacturing?

I’ve read some similar answers yet I find that confusing because I scrub with pbw I just worry it could be some sort of bacteria

 

[bruce_the_loon]

I’ve read some similar answers yet I find that confusing because I scrub with pbw I just worry it could be some sort of bacteria

I don't know if PBW is a good enough cleaner when it comes to machining oils. You might consider a stronger degreasing agent like the good quality washing up liquids that get rid of cooking fats. Possibly using the washing up liquid with hot water as well.

 

[rburrelli]

I’ve read some similar answers yet I find that confusing because I scrub with pbw I just worry it could be some sort of bacteria

Barkeepers Friend is your friend when cleaning stainless steel. Especially the first cleaning prior to use.

 

[aeviaanah]

I have had this happen in most of my brews since I started using stainless steel I do a hot soak with pbw and then Sanitize with star san I don’t think it’s producing off flavors but i don’t think it’s normal

Do you use brewtan b or any gallotannins? I've noticed a purple hue to the foam in mash and kettle whenever I use it

 

[Chris112]

Spike instructions state to just thoroughly wash new stainless with dish soap to remove leftover oil from manufacturing prior to use. Then I also wash with PBW.

Ss brewtech says to use TSP first, which also cleans manufacturing oils then brewery wash and then to passivate with mild acid.

My first two brews in my new spike flex had a purple spot on the krausen ring but after that no issues. Those brews weren’t bad either.

PBW doesn’t clean machine oil well enough so it may be worthwhile to scrub with a strong dish soap solution or normal amount of TSP solution.

Barkeepers friend will take off the volume etching if you’re not careful, I would not use it.

 

[skunkape]

Perhaps it's irrelevant... but what did you ferment? What yeast was used? Any additions? Fruit, wood, dry hops?

 

[hotbeer]

Fresh yeast or is this yeast you save and re-use?

 

[beersk]

Do you use brewtan b or any gallotannins? I've noticed a purple hue to the foam in mash and kettle whenever I use it

I was going to mention this as well as I've noticed something similar. Certainly was weird the first time or two I experienced it.

 

[glick]

When I bought my SS Brewtech brew bucket it came with step by step instructions on how to clean and prep the stainless steel prior to first use. It involved a thorough cleaning with tsp followed by passivation with a strong Star San soak. I have had 0 issues with my brew bucket and have been using it for years.

If I were you I’d go back to step 1 and get those fermenters cleaned. Anything that’s turning your krausen purple can’t be good for you.

 

[DavidWood2115]

Resurrecting a dormant thread…

I recently had the same issue with my CF10. It’s several years old with many batches and no new equipment so there is no way this is due to machine oils. The beer turned out great, possibly my best hazy to date, so I’m at a bit of a loss. Of course the beer was so good the batch did not survive the gathering I took it to, so there is no chance of determining if the purple scum would affect flavor longevity.

I brewed the same beer a month earlier, without the purple krausen. The only substantive process difference was that for this batch I dropped the whirlpool temperature to about 170 (was aiming for 180 but over shot). I think the cooler whirlpool definitely helps retain aromas, but is it possible it doesn’t kill something or denature something that could cause the purple scum?

 

[Skeeter686]

I brewed the same beer a month earlier, without the purple krausen. The only substantive process difference was that for this batch I dropped the whirlpool temperature to about 170 (was aiming for 180 but over shot). I think the cooler whirlpool definitely helps retain aromas, but is it possible it doesn’t kill something or denature something that could cause the purple scum?

Admittedly, I don't brew hazies, but I thought I'd heard that oxidation can cause hazies to turn purple. Do you think that might be a factor somehow?

 

[DavidWood2115]

I haven’t heard of the oxidation—> purple link, but I’m pretty anal about cold side oxidation so I don’t think that’s the cause. And I’ve followed the same cold-side process for multiple batches, so I don’t know what’s different about this batch.

 

[sibelman]

When my Flex was new there was some black crud. Never purple. Weird.

 

[Dland]

Resurrecting a dormant thread…



I brewed the same beer a month earlier, without the purple krausen. The only substantive process difference was that for this batch I dropped the whirlpool temperature to about 170 (was aiming for 180 but over shot). I think the cooler whirlpool definitely helps retain aromas, but is it possible it doesn’t kill something or denature something that could cause the purple scum?

View attachment 834093

Actually, 170F is a better target temp for than 180 for the whirlpool, more likely to avoid DMS. I cool to 160 before hop step all the time, never had purple stuff, or the brighter yellow granulars, for that matter, just tan yeast residue.

Did you dry hop or add anything else in fermentor?

 

[DavidWood2115]

Did you dry hop or add anything else in fermentor?

Yes. It was dry hopped with 5.5 ounces of Citra and Mosaic T90 pellets. I use a hop cannon to limit the O2 ingress during dry hopping.

 

[Dland]

I'd guess the colors are made in some reaction with hops then. There is off chance an infection came in with them, but since the beer was good that is less likely.

 

[AmarikinBrew]

Wut the hell are you doing brewing psychedelic shrooms for MAN?
Then again, I really donknow anything about that. Anymore. Really.