Mold in dried kräusen on conical wall

[manu]

I've been happy with my conical fermenter, though I've seen an unsettling trend in the first 3 batches I made in it. The upper part of the dried kräusen is black, which I assume is mold. I've been extra vigilant about keeping things clean, and limited the potential oxygen exposure. For the last batch, I didn't even draw any yeast or trub in order to avoid sucking in oxygen. I assumed there would be enough CO2 to prevent mold from forming. The last batch also had an addition of oak chips that where thoroughly boiled for 20 minutes.

Any thoughts on what this black stuff is or why it keeps on coming back?

 

[DurtyChemist]

It's well documented in the equipment section. Look up brew bucket black ring or mold.

 

[rat01man04]

I've got teh same thing from my first batch in my new Blichman Fermenator...

 

[manu]

The black stuff got less and less, and by batch #6 it was completely gone. At this point I don't think it was mold, but rather some substance remaining from the manufacturing process. Cheers!

 

[rat01man04]

Thanks. How did your beer turn out? Over time and subsequent batches? I haven't tasted mine yet

 

[Ashevillain]

Machining oil? :/ was deff all over my kettle when i first got it. Had to reallly scrub it until white rags were no longer getting black residue.

 

[Tiber_Brew]

Did you clean your conical with TSP prior to use?

 

[rat01man04]

I thought I cleaned it thoroughly, maybe not enough. Something I'll focus on before the next brew. That said, I just did a 48 hr PBW soak and the black line left behind from the (mold?) is now gone. You can kind of see where the line was, but that's just a different shade of stainless steel now. I plan on doing another PBW clean/soak prior to my next brew. I'm hoping that's the end of it. I'll keep everyone posted

 

[rat01man04]

And I'm sorry that pictures keep posting upside down... I'll turn my iPad around next time!

 

[Tiber_Brew]

Prior to brewing with your conical the first time, it's best to clean it with either TSP (manufacturer recommended) or similarly effective cleaning agent. I went as far as to clean mine with both TSP and Micro 90. It might be overkill, but I'm fairly confident that all machining residue is gone.

I don't think PBW alone will sufficiently remove machine oil and manufacturing residue (as evidenced by the "black ring").

 

[TheBrewBrotha]

Could Bar Keepers Friend be used instead of TSP?

 

[manu]

Just for the record, I cleaned mine with TSP first, then PBW and then passivated it with a high concentration of StarSan before first use. I still got the machine oil ring at the top.

I wonder if the alcohol in the beer caused the remaining oil to separate from the conical. Anyhow, the oil rose to the top and attached to the tried up kräusen on the side wall. I doubt too much is remaining in the beer that I bottled. I didn't notice a flavor or aroma impact. Again, the issue subsided for me after a few brews.

 

[manu]

Could Bar Keepers Friend be used instead of TSP?

BKF is awesome. I use it on SS all the time, even on my cooking pots and pans. However, it should be said that BKF will ruin etching like volume markings.

 

[Tiber_Brew]

Just for the record, I cleaned mine with TSP first, then PBW and then passivated it with a high concentration of StarSan before first use. I still got the machine oil ring at the top.

Interesting. Makes me want to double check my kräusen ring a little closer for black residue after I keg my next batch. (I just recently started fermenting in stainless conicals.)

 

[TheBrewBrotha]

BKF is awesome. I use it on SS all the time, even on my cooking pots and pans. However, it should be said that BKF will ruin etching like volume markings.

Awesome as I too use BKF on all SS items. Thankfully, knocks on wood, i haven't any damage to my etchings