Just racked my beer from the two Genesis plastic brew buckets into 5 gallon kegs. There is a definite residual odor that is lingering, mainly of yeast. The buckets have been thoroughly cleaned, and sanitized.
How do we eliminate this odor?
I don’t think you do. I ferment in plastic and they always have a faint smell of beer even after cleaning and sanitizing. You could wash them with the hottest water you have and use some Craftmeister cleanser, Oxi, PBW, etc. and let it soak and then let them air out in the sun but honestly… the smell will probably still be there. It will not impact future batches.
Yep, same here. When I fermented in plastic the smell of yeast and hop oils was permanently embedded in there. It never affected the beer.
Think of it as a cast-iron pan or maybe a sourdough starter… there is a little bit from the last batch in the next batch. No, actually don’t think of it that way. It’s gross. But I promise that you could make a super dark and hoppy high-ABV batch and then make a delicate Caribbean Lager in da same fermenter on the da next batch and EVERY LITTLE TING… GONNA BE AWRIGHT, mon. 
Strong caustics, like lye, can destroy molecules that may be creating aromas. Find some lye at your grocery and mix up a strong solution to soak the interior with. Do be very careful since a lye solution will quickly destroy your skin and eyes.
Thanks for the feedback! It has been so long since plastic was used that I forgot about any odor issues.
I plan to brew another light lager in a few days, and will give these Genesis fermenters another go,
Bleach is fine just rinse it well. Removes odors and stains.
But if it destroys the skin in your nose you won’t smell that offending odor anymore!
The odor isn’t a problem for future batches. If it really bothers you, try baking soda.
Not to be critical but I don’t know if I would want to use bleach. That could impart an chlorine odor in the plastic, IMHO. If beer does it, what’s to stop bleach from doing that, again IMHO. But that is just me.
I agree with Martin that caustic will do the job, although it is dangerous to use so be careful. If you have a good relationship with a local brewer, you might be able to talk the brewer into selling you some. That said, I have never had a problem with the beer odor in a plastic bucket effecting a subsequent batch and never worried about it.
I think this is the key right here. You have a solution looking for a problem and there really is no problem. I make A LOT of wimpy gold lagers and they are good tests for whether a flavor would be transferred from the fermenter to the finished beer. It does not happen.
This is most reassuring, so full speed ahead with the next brew…Munich Helles.
There is nothing wrong with using bleach to remove stains and odors. Just needs rinsed well. Dose it correctly, don’t use it on stainless, rinse it well and it is perfectly fine. I’ve done it a hundred-bazzillion-gazillion times.
Definitely agree that the previous batch odor is not going to be an issue, but if you need a tool to remove stains and aroma bleach is probably the most convenient to use.
Tried baking soda? Works great for me. But as we all said, its not problem
See reply #8
Thank you. It does not bother me now that all of you “pros” have weighed in on the issue.
When you brew with that vessel again, give it a good whiff after it’s been cleaned (soaked in hot water with a brewery cleanser or whatever) and sanitized using Starsan, IO-San or Iodophor. You will notice that the odor of the previous batch is much less pronounced. That’s one good sign that your new batch won’t be impacted by the previous one. I switch off between two plastic fermenters now. When I clean them after transferring from them and I put them back into my beer bunker, the smell is quite strong. But after a good cleaning and sanitizing it’s fine.
The other thing that can help is good old sunlight. Which you probably have a lot more of in TX than we do OR right now! Try leaving it open in the sun for a while. It my help.
ETA: now that I think about it, didn’t it snow down there recently?
My daughter is in Austin and told me it snowed on Sunday. :
Every summer I give my buckets a good deep cleaning and a full day or so of sun (repeating as needed). They look bright white and then I start to use them again and the inevitable discoloration kicks in…but I don’t ferment much in buckets anymore (other than SS Brew Buckets). My buckets hold Iodophor, Star San, BLC mixture, you name it, from time to time…generally I just use them to capture the water from chilling to re-use for cleaning after the wort is racked to fermenter, or earlier in the brew day to weigh out grain bills and catch crushed grain in the underside of my JSP mill. Sometimes I temporarily store extra grain in them, when I stock up in advance of some bigger brew days. They really are handy and stepping up from using them as fermenters doesn’t mean that they will not be used!