I am having infection issues and I can not figure out where things are going wrong. I all grain brew and prior to now have not had any issues, I have been brewing for a few years. I use a 1/2 barrel keg and Home Depot round coolers for brewing. My chiller is placed in the keg for the last 15 minutes of the boil. Once off the burner the only things that touch the wort are a thermometer and a large spoon for airation which are both kept in sanitizer prior to use. I brew in the garage and I place the keg outside the garage door while the chiller does it's thing. The wort is always covered with a metal screen to avoid any insects etc. From there the wort is drained into primary buckets and into the basement it goes with a tube hooked to a 3 piece airlock ran into a 2 quart jar which has not gone dry.
I brewed a blonde and an Irish Red on the same weekend, both turned out very sour. The blonde was very cloudy in apperance. Both were let to sit for a while but were finally dumped, the taste was very bad. My next brew was a Southern English Brown. It had a slight sour taste, but just faint. This beer is currently kegged and is borderline drinkable, basically has a tart taste to it that the style should not have. These 3 were brewed within a week of each other, nothing was changed as once I realized I had a problem they were all waiting for the keg. Last I brewed a Kolsch knowing I had an issue prior. I bought new primary buckets and high-temp hose thinking my problem may be either from transfer to primary or primary itself. The kolsch is bad. After 3 weeks in primary and a gravity of 1.010 it has a slimey krausen on it, smells like bread, appears very cloudy and has a sour taste.
Ideas? Am I correct in assuming the problem lies starting with the second it comes off the burner? I really was hoping the problem lied in the primary or hose and now I'm stumped... As far as yeast I used a washed yeast starter, dry yeast and a smack pack so I can not really blame it on yeast handling either. I do not open my primaries for any reason up until right around the 3 week mark when I am ready to keg or transfer so I do not suspect anything getting in that way. Where should I look next?? Thanks in advance.