Dilema.......why does my beer change from pretty good to bad

[Elysium]

I have been brewing for a year and thanks to this forum my brewing techniques have improved a lot...and I mean it.

Now....I am facing a problem I dont understand (which might be caused by something I still dont understand but I need to get to the bottom of this).

The problem is simple: my beer is stored in a storage room where it bottle-carbs and conditioned. The room is okay when it comes to temp 68-75F.

However....my beer, after a few months, changes the taste.....but not to something good and superb, but to something slightly rancid, acidy. Any ideas why?

 

[NervousDad]

I'd say infection, maybe lacto, which can create a sour/acidic taste.

 

[Elysium]

I'd say infection, maybe lacto, which can create a sour/acidic taste.

The forced wort test is always negative. I'd like to rule out infection.

 

[krenshaw]

is this just one batch or happens most of the time?

 

[kh54s10]

We'll need more details, such as recipes, type of brewing, procedures, cleaning and sanitation, fermentation temperatures etc.

Common culprits are high fermentation temperatures or bad water chemistry.

Try to narrow it down and change that procedure or ingredient (water) and see if that makes a change.

Otherwise, as I said, more details will be needed.

 

[Trox]

What are you using for your cleaner and sanitizer? If I remember it correctly you had asked before about creating your own from local supplies since the ones most of us use isn't readily available in your area. I can't recall if it was the cleaner or the sanitizer that you was asking about making at home, or what the end result of the thread ones, but if you did blend your own it might be leaving some residual off flavors that don't start coming through until a few months later.

 

[pdietert]

Are you purging the air from the head space in your keggs?

 

[pdietert]

Also, what is "a few months" and what types of beer are you brewing? 68-75 seems pretty warm for storing home brew for longer than a couple of weeks unless you are trying to age it quickly. At those temps even a very small infection (that would be suppressed in cold storage) could be a big problem. The forced wort test is not going to test sanitation from fermenter to keg nor the keg itself.