Belgian ale getting sour with time

[iluretar]

Hello, i've been having an issue when brewing a belgian ale, as the title says it gets sour/acidic with time. It starts well and within a week of bottling or keging it starts to go sour. I've cleaned all the equipment several times with pbw, and even caustic but the issue keeps happening. The thing is that in between batches of this belgian i have brewed several others without any issue, inclunding ambers, browns, wheat and saison. Im in my 5th batch of belgian that has this issue in the course of a year and around 10 other batches of other styles without issue. Last one was even fermented in a brand new fermenter and plate chiller and still the same issue. Ph at bottling is around 4.4 and it goes all the way down to 3.9 by the time i dump it. I have changed yeasts, added nutrient and also an oxigenation system for the wort thinking it may be yeast related but no dice. Any suggestion is welcomed, thanks.

 

[hotbeer]

I call myself being a little fastidious about cleaning my equipment and sanitation. Recently I had some random bottles from a batch earlier this year seem to be infected with something that affected their taste and took the SG down to 1.001 from the OG of 1.010.

For this, I just changed up my sanitation procedures some by adding a soak for the bottles and equipment in some water with chlorine bleach before rinsing and using my usual sanitation stuff.

No issues so far. But I haven't any beer in bottles that have as much time on them as the others were when they were found infected.

So the short answer will be to soak all your stuff in a bleach solution after thoroughly cleaning it, then go on about your normal procedures.

You do disassemble your spigots, bottle filler, IC, etc., and run a swab through your lines when cleaning them don't you?