Riddle me this (sour beer content)

[Bugeater]

I would venture a guess in the direction of a mold problem in the vicinity of your furnace/air conditioner unit. Sounds like an airborne infection getting spread by the fan. At a minimum get the furnace filter changed assuming you can get access or can get the landlord to do it.

Wayne

[Evan B]

I would venture a guess in the direction of a mold problem in the vicinity of your furnace/air conditioner unit. Sounds like an airborne infection getting spread by the fan. At a minimum get the furnace filter changed assuming you can get access or can get the landlord to do it.

Wayne

We actually have baseboard heaters and no a/c (a/c doesn't exist in seattle). So air flow only happens with open windows, which doesn't really happen this time of years. Which really all just adds to the mystery.

Awesome suggestions so far. Thanks guys! hopefully one of these days I'll shake this funk off

[ipaisay]

Describe to us your "cleaning" routine. Ie PBW->star san/idophor? how often do you change your transfer tubes? do you clean up right after each brew/fermentation session?

[Evan B]

everything gets a healthy PBW soak followed by starsan. On the cold side, the beer touches nothing that didn't just come straight out of starsan. i change my tubes almost every brew out of paranoia

[brewinhard]

What type of yeast are you using? If you are repitching, you could be repitching infected yeast. If you are using a fresh starter, then maybe your sanitation gets screwed up there. If you are using dry yeast, are you sanitizing the yeast packet AND the scissors? I typically let my equipment sanitize in star san for a minimum of 3 min. out of paranoia.

[Evan B]

i'm getting my yeast from the brewery down the street. we always thoroughly clean and sanitize the bottle before harvesting the yeast in to it. i always get this when they're harvesting to pitch their next beer, so I know that everything's clean on that end. i soak the bottle in star san while the boil is happening

[cosmo]

Are you sure it is an infection? I say this because I have recently started getting batches that seemed a little sour. My sanitation is impecable (like yours sounds), PBW -> Starsan. Everything that touches the wort is either boiled or right out of the starsan. I make sure the A/C is turned off for at least a half hour before the boil stops. I always use a fresh smack pack of yeast in a starter that is boiled in a flask and put on a stir plate. I have noticed this more when I went to cooler fermentation temperatures and temp control. I didn't get any sour flavor a year ago when my sanitation was much worse. I am pitching the correct amount of yeast as indicated by the Pitching Rate Calculator. I am thinking the only thing left is maybe not enough aeration. I was shaking / rocking the carboy for 4 minutes prior to pitching the yeast. The batch I brewed up last weekend I did the shaking / rocking four times at 4 minutes each with 5 minute rest in between. I will see in a few weeks if that made a difference. I also bought an 02 aeration system from William's Brewing which I plan to try on a batch of Kolsh next weekend. I just wanted to make the point that it may not be infected. It could be something else in the process that is causing the yeast to put out off flavors. I could be wrong, but it's something to consider.

[ipaisay]

I have to ask the same question: Are you sure that it is sour? See a pedicle? even a bottle pedicle? Maybe it's your ingredients and possibly a lack of good fresh quality ingredients? That will give you some flavors if you go from good ingredients to lousy ingredients. Maybe not sourness but you could be getting you a "tang". (Pootang is fun too!) I made two beers this summer from malt I won at a Homebrew comp and the beers were horrible. I must have been really old malt.

Sounds like you are as clean as you can get! Even better than I am.