What causes excessive foaming in bottles?

[shenanigans]

I made a double IPA in February and the beer turned out to have an off-flavor which tasted like a harsh metallic flavor. Although I kegged majority of the batch, I also bottled 1 gallon. This was the only beer I ever had to dump and have been rather uncertain as to what caused the harsh off-flavor. Today I wanted to see how the flavor may have changed but when I took the cap off the cold beer began to foam excessively. What causes a beer to foam excessively similar to if a bottle of pop is shaken up and starts bubbling out of the top?

I have only had this happen once before with a beer which was fermented with a really old batch of rinsed slurry.

Could I have gotten an infection or contamination from the rinsed yeast? Currently I feel the yeast must have been the cause of the off-flavor but the mystery still continues…

Any information is greatly appreciated; cheers!

[mrv]

Over priming/under attentuation can cause foaming. An infection that eats through fermentables the yeast didn’t touch will also cause foaming.

Iron in your water, contact with steel (besides SS), or unseasoned aluminum could cause a metallic taste. According to John Palmer, hydrolyzed lipids in
poorly stored malt will to. I’m not familiar with that.

What hops did you use? I get a metallic taste from too much Willamette.

I don’t know of an infection that gives a metallic taste. Could be wrong, though.

[shenanigans]

I used Centennial, Simcoe, and Columbus hops. It is weird because the beer tasted great until it was kegged/bottled. Also I did a double dry-hop and had never done this before so maybe something happened with the double dry hop.

The beer did attenuate fully and I have never over primed my beers and the off-flavor was in both the keg and bottles.

Just wish I knew what caused it because I have never experienced it before.

[alss]

This is a puzzle. Seems quite possible to me that the metallic taste and the over carb could be two separate issues. The foaming could be an infection from contaminated yeast like you had before. Perhaps the metallic flavor is there on other batches but is greatly intensified by the over attenuation caused by the infection. Do you ever brew highly attenuated beers, like a Saison or a light lager?

[dmtaylo2]

Bacteria can generate metallic flavors. It’s possible you’ve got an infection. Not for sure, but possible.

[shenanigans]

I talked to a few staff at NB and they thought an infection may have caused the off-flavor.

I have not made a highly attenuated beer such as a light lager or a saison. Currently, I am still trying to acquire a taste for belgian beers.

Anyway I plan to make another double ipa this weekend!