Rotted taste, off flavor after primary

Any pellicle on the beer?

 

Could be yeast. If there is any haze to the beer, the yeast could be entrained in the beer. Yeast itself can have very umami, meaty flavors. Does that describe it at all?

Otherwise I'm wondering if you're fermenting in plastic. I have had this problem multiple times in the past. All of a sudden every beer starts getting contaminated. Soft parts such as buckets, hoses, airlock bungs, can harbor wild yeast and bacteria that are basically impossible to kill, thus infecting every batch until these soft parts are replaced. Consider the possibility.

 

I would stop aerating. Wait until you are ready to pitch. Wort, if the post boil sanitation is sound, should be pretty sterile. No need to give whatever made it in there o2. Also, I'm not a hot side aeration expert, but depending how hot the wort is when you were oxygenating, you could be getting some affect from that.

 

As a gardener and tomato lover I am very familiar with that "turning" tomato flavor, which, yeah, there is still some "umami" there since tomatoes have tons of "umami", but is still a very distinct and highly unpleasant flavor.

At this point I am leaning toward infection. It sounds like you had one suspected pellicle. And a full blown pellicle can take a long time to develope. You likely packaged before it had time to be highly noticeable.

Were the spots of mold in the fermenter when the beer was present? If so that is another good indication.

Are you reusing your yeast? If so stop as it may be passing on the infection.

I doubt the sanitizer is causing that much of an off flavor.

Look up the diluted bleach solution in How to Brew, which if i recall used to have dilutions for sterilization and sanitation. Use the sterilization dilution over the appropriate period of time, if not longer. Do a thorough immersed soak. Rinse well and try again. If the problem repeats again I would pitch my plastic fermenters, hoses, etc. and but new.

 

I'm a big believe in scrubbing my plastic brewing vessels followed by bleach sterization followed by a good rinsing with HOT water and finally rinse with starsan solution.

Good rule of thumb is if the manufacturer says how much add to a given volume of water, use the full amount. Cutting back can result in wasted product, possible infection or not a complete cleaning.

 

My primary fermenters are 7.9 gallon buckets. My practice is to store these buckets with a bleach/water solution between batches. Something you may want to consider doing as well.

I use a two fluid ounces of bleach (8.25% Sodium Hypochlorite) per 8 gallons of water.

Cheers!

 

yep it is, but perhaps you are seeing the result of using less pbw in the beer. As @JackHorzempa stated keeping your fermenters with the bleach solution will help and bleach is a cleaner as well. I have stopped using PBW and only use cholrine, hot water and scrubbing with no issues. Just remember to completely rinse out the chlorine with hot water or it will ruin your beer.

 

If your wort is in the 70 degree range I doubt your problem is due to hot pitching. I suggest rereading the above posts and try to brew again using the above methods, then report back.
It does seem to be an infection problem. and remember if you are using starsan it is not a cleaner, just a contact sterilizer.

 

Mold needs moisture. Are you storing your fermenters wet? I store my fermenters upside down with spigots open and loosened for cleaning. I always use my leftover StarSan (or Trichloromelamine for plastic fermenters) from racking/kegging to soak the fermenter before storing. Plastic fermenters never get scrubbed with anything harder than the soft side of a scrubby sponge. Any vinyl/plastic gets rinsed/backflushed immediately. These precautions have worked for me for over 10 years and 100s of batches without a problem so far.

 

Carboys are tough to clean but i learned to put some hot water/star san and wash clothes inside then spin so the cloth runs along the walls of the carboy. Your back will feel it but it helps.

 

It's time to pitch all plastic and rubber and start over. This is the only way I know to prevent future infections. Believe me, I've tried everything.