Beer Smells Like Mop Water

[ChiechiBrouw]

A few months ago we bought a second fridge, so the old one was promptly populated with a corny keg, but apparently I'm too stupid to clean it properly.

I soak everything with Chemipro Caustic in warm water, including inverting the keg in a bath of the stuff; about 10-20 minutes per soak. I pressurize the keg and then flush about 10 L of Chemipro solution through it. I take apart the picnic tap and soak it along with all the tubing and fittings. I then repeat the entire process with iodine solution and then several times with water.

No matter what, though, the slight smell of beer-funk remains. After carbonating, even the first beer I pour has a subtle "mop water" smell in the nose that steps all over the desired hoppy aroma. It is hard to tell how prevalent it is (no one else seems to notice) or if it gets worse over time, because I'm so fixated on it that I can't taste anything else. (It is subtle enough that I don't notice it when I keg a stout or porter.)

What am I doing wrong here? I'm assuming this nastiness is from mold hanging out somewhere in the system, but it's just a corny keg (brand new, not refurbished) with about six inches of vinyl tubing and a picnic tap--where could it possibly hide that it would survive Chemipro and iodine? Do I need to completely disassemble the keg--dip tube and all--every time I clean it?

 

[Ace_Club]

Okay, had to do a little research on Chemipro, but it looks like it is a similar cleaning agent to PBW.

Anyways, after you perform your PBW wash/soak/cleaning and your iodine sanitation, why are you rinsing with water? IIRC, iodine can be used as a no-rinse sanitizer. So in the future, skip the multiple rinsings with tap water after the iodine sanitize step (unless the directions on the iodine packaging suggest otherwise, though if that's the case I'd strongly suggest finding a no-rinse sanitizer that you can buy).

Also, you should definitely be completely disassembling the keg, dip tubes and all, every time you clean/sanitize. Get yourself a diptube brush and run it through the diptube during that cleaning as well.

See how that works out for you.

Oh, one more thing, try omitting the mop water from your recipes. That also might help.

 

[ChiechiBrouw]

Of course--leave the mop water out of the secondary, why didn't I think of that!

The rinsing is actually because the iodine cleaner I use tends to foam up quite a bit and the foam gets stuck in the top of the keg. I'm worried that the foam is mostly composed of the polymer stabilizer they add to the iodine cleaners and that it might mess with my beer. I suppose "several times" is not really what I meant to say; really I swirl water around inside and dump it until no more foam comes out.

I will have to dig around for a dip tube brush--thanks for the tip. I don't take my keg apart when I clean it unless I kick it on the weekend because during the week I don't have a lot of time... I suppose if waiting for the weekend to keg my beer eliminates the mop water smell, then it's worth it.

 

[Ace_Club]

If it's specifically stated on the packaging as a no-rinse sanitizer, than I wouldn't worry about residual foam.

 

[ChiechiBrouw]

Success! I switched to one of those no-rinse oxi-cleaners, and got myself a 27 mm wrench to disassemble the keg and voila--no more mop water! Now I get a nice burst of fresh hop aroma when I pour.