Sourness at end of keg

[moger777]

So I've kegged two beers so far. Both times I noticed that the last few beers were particularly more sour than when they were first kegged. I keep my kegs refrigerated and clean and sanitize before adding the beer. I'm wondering if this is normal that the last few beers don't taste as well as they should or if there is a flaw in my sanitation technique. I'm wondering if maybe the beer lines get dirty and cause sourness as the beer runs out since I don't clean till the beer runs out. The reason I don't think it's the lines is that it usually is not noticeable until there is less than a gallon left in the keg and I also keep the beer line in the fridge with the keg (I got one of those cheap taps, not one of those fancy beer tower types). It might be a bit early to reach a verdict since I've only kegged two beers. Is it worth mentioning that both beers have been extracts (extract twang more noticeable at end of keg?). Any help appreciated.

 

[Kai]

If it's sourness or tartness, it seems very likely to me that your batches have been infected in the keg. Sanitise the thing like there's no tomorrow, try replacing your o-rings and beer-line tubing, do a meticulous batch (including meticulous sanitisation at all stages) and see if the problem persists.

 

[david_42]

I clean all of my lines every month or so and when I'm putting a new keg on. Low infection levels can take a long time to build up, but once they are established, every pint you pull will be sour.

 

[Bobby_M]

I clean ALL 4 of my lines anytime ANY of my kegs kick. That ensures they're getting cleaned on more of a regular basis. I've never had a beer sour in the keg.