Stouts going sour

For those who have not experienced it, an infected beer can cause gastro-intestinal distress, to say the least.
I had a bomber once all by myself and was not a happy camper that evening. Yes, it was sour, (wasn't supposed to be) but I didn't mind.
It has been mentioned here in the past, but I didn't understand until it happened to me.

 

Of course, it depends on the bug(s).

 

I don't know if this is the issue, but barrel-aged beers, stout or otherwise, are more likely to be soured/infected. There's a higher chance of some unexpected bit of bacteria left in a barrel or floating in the air during transfer of the beer. Most brewers with large barrel programs (like Goose Island, or Founders) pasteurize their barrel-aged beers to avoid this, but plenty of brewers don't pasteurize.

 

One of my favorite beers Ive had is a sour stout. Farmhouse Ann from Forest and Main. It was called a stout at the bar in 2013 but is now called a wild ale on Untappd.It was dark, roasty and chocolate with a mild sour funk.

Enjoy