Invisible lacto infection?

ericd · 08-15-2009, 10:00 PM

A lot of my beers have this sour, harsh off flavor even after adequate aging. My know-it-all homebrewing friend (who in his infinite wisdom hit a whopping 50% on his last batch

) says it's a lacto infection. The thing is I've never seen any signs of infection in any of them and they smell fine. Where else could the off flavor be coming from?

**david_42** · 08-15-2009, 10:09 PM

Lacto will sour a beer long before it is visible.

ericd · 08-15-2009, 10:13 PM

How long and where does it usually hide?

**Yooper** · 08-15-2009, 11:56 PM

Quote:

Originally Posted by ericd

How long and where does it usually hide?

It can be in grain, so that's why you don't crush grain where you ferment. It can be in tubing, buckets, etc.

The first sign of lacto is generally a sour ness. Not vinegar sourness, but sour like soured milk. The next sign is that the beers will gush when you open them, as the lacto continues to ferment in the bottle. At that point, if they don't taste bad, you can still drink them but drink them quick! Lacto gets worse with age. A 6-8 week old beer might taste fine, but if it gets sour as it ages, that's a good sign of lacto.

If you have lacto, you'll have to bleach bomb all glass and throw away all plastic.

ericd · 08-16-2009, 02:14 AM

Okay, it's definately not lacto then, it gets better with age (but doesn't go away) and the only time I've had problems with gushers is my last wild beer.

Could it be my water?

**Yooper** · 08-16-2009, 02:23 AM

Maybe. Could you describe the flavor a bit better? Harsh could be tannin extraction, or hard water with lots of hops. "Sour" could be yeast, ingredients, or even tannin extraction (thinking of astringency, rather than "sour" in that case).

Could you give us a sample recipe, and sample technique? How is your water?

What were your fermenting temperatures like?

**Cpt_Kirks** · 08-16-2009, 08:49 PM

If you keg and get a lacto infection, it doesn't gush, but I think it does move quicker. I had a batch split between a three gallon and a five gallon keg. They turned to vinegar pretty fast.

I poured most of 8 gallons of carbonated vinegar down the toilet.

**Yooper** · 08-16-2009, 09:37 PM

Quote:

Originally Posted by Cpt_Kirks

If you keg and get a lacto infection, it doesn't gush, but I think it does move quicker. I had a batch split between a three gallon and a five gallon keg. They turned to vinegar pretty fast.

I poured most of 8 gallons of carbonated vinegar down the toilet.

that doesn't sound like lacto- that sounds like acetobacter. Acetobacter is the bacteria that turns alcohol into vinegar. Often carried by fruitflies.

ericd · 08-17-2009, 12:12 AM

Yoop, if you've ever taste one of the little fruits off a bradford pear tree when they're still hard, that's the closest I can describe it. Puckery, sour, and kinda waxy.

**Yooper** · 08-17-2009, 12:20 AM

Quote:

Originally Posted by ericd

Yoop, if you've ever taste one of the little fruits off a bradford pear tree when they're still hard, that's the closest I can describe it. Puckery, sour, and kinda waxy.

"Puckery and sour" really sound like tannins to me. Can you imagine using a tea bag, and then sucking on the tea bag? That's what harsh tannins taste like. Is that the flavor you're picking up?