Rubbermaid mash tun smells kind of sour

[supermoth]

I just took the lid off my Rubbermaid mash tun and it smells. It always keeps a bit of a grain smell from batch to batch, but now that smell has turned a bit sour.

Every time I use it I clean it out immediately afterward. I hose it down (with cold water) and use the soft side of a sponge to make sure there is no residue. The false bottom parts get taken apart every time. Just two days ago, I took apart the ball valve stuff and washed all the pieces and made sure there were no obvious leaks into the inner insulation. One thing I've always been suspicious of is the etched volume markings on the inside of the cooler.

OK, so I just went back and sniffed again and in the few minutes it's taken me to type this (and crack an Apfelwein ,) it's aired out enought to where the offending smell has gone away. Now all I smell is the residual nice smell of grain, but the sour memory lingers.

Does anyone have helpful cleaning advice? Reassurance? Admonishments? Recommendations for Oxyclean?

 

[samc]

Oxiclean for sure after every brew day. If it still persists you might consider some bleach solution. After cleaning and drying you should store it upside down and open to allow it to air out.

 

[maida7]

It's probably lactic acid from the bacteria on the grain. This SHOULD NOT be a problem. Unless it's like overpoweringly smelly, I doubt it will effect your next batch of beer. Go ahead and clean it if you want but don't go crazy. RDWHAHB

 

[lschiavo]

Oxiclean for sure after every brew day. If it still persists you might consider some bleach solution. After cleaning and drying you should store it upside down and open to allow it to air out.

This made a huge difference for me. Let it dry out. If you keep the lid on with moisture something will grow in it.

 

[supermoth]

Thanks everyone. And thanks to everyone on HBT who turned me on to the wonders of Oxiclean! It's amazing stuff.