Soapy taste in beer - almost solved - getting close

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passedpawn

passedpawn

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I've had 5 batches of soapy beer, spread over the last 6 years. It's fairly random when it happens, so I've had some trouble fixing the problem. Recently, I had an Aha! event that REALLY narrows down the possibilities.

The flavor, as I said above, is soapy. Don't know how else to describe it. I've done countless searches for info and attempted to find a common denominator between the soapy batches, but could not. I thought it was water (or related chemistry), oxidized hops, etc. I really thought it was dryhopping with old Centennial (I store in vac bags in freezer though).

I usually take a taste sample of one of the fermentors during kegging (I make 10g batches and split into 2 fermentors). I don't believe the flavor ever existed coming out of the fermentor, but I'm not sure - my notes only indicate the problem after kegging.

Aha!
But recently, I split a batch of an ESB after the boil. After fermentation, one keg was really good, the other undrinkable - soapy. The yeast was rehydrated and shared between the two fermentors, so it can't be the yeast or malts or hops or water because they were shared. It must be something in ONE of the fermentors or kegs. I think that means infection or leftover starsan or oxyclean.

Thoughts?
 
What material are your fermenters made out of? Starsan isn't likely to be the culprit, but Oxyclean maybe.
 
spittybug said:
What material are your fermenters made out of? Starsan isn't likely to be the culprit, but Oxyclean maybe.
Click to expand...

PET (big mouth bubblers). I've got six of them, and they normally don't cause this, so not that.

I do use the normal oxyclean with the blue aromatic crystals. I rinse pretty good after a soak (I don't always do a soak though, only after IPAs). I'm going to switch to the "scent free" which is what I used to use a long time ago. Maybe I'm leaving one of those things in there, though I rinse upside down with a hose/sprayer so seems unlikely.

I store the fermentors with strong starsan solution, and only swish/dump before filling. I know starsan isn't a soap but an oxidative cleanser, so I don't really think that's the problem, BUT... the first time I ever had this flavor was after I had cold-crashed with a blowoff tube still connected, and the fermentor sucked back a bunch of starsan solution from the blowoff reservoir.
 
"they" say don't fear the foam, and this is true to some extent with that product. But I make an effort to have cleaning compound residues in any of my brewing vessels at a minimum to none.

Normal sanitation for me does include a very hot PBW solution, quick fresh water rinse though pumps, then starsan or saniclean. Then thorough drain off, foam and all.

All that said, I have had beers that tasted kind of soapy at some stage of conditioning, blamed on hop oils and such, but I don't know, usually ages out.
 
This thread is definitely interesting to me because it’s not something I’ve thought a lot about, but now that I think about it, it is definitely something that I’ve experienced....more than I’d like to admit.

I feel like my recipes are on point, my processes are very good, I limit oxygen ingress really well, but I always seem to have slightly soapy-ish flavors. I use oxyclean as my main cleaner for my two kegs, which have been used a lot, and also my primary fermentater. I’m admittedly not the most anal person when it comes to cleaning and sanitation, so I think this could definitely be something that I try to correct.
 
Dland said:
usually ages out.
Click to expand...

My soapy problem most certainly does not age out - at least, it doesn't age out in the keg. I've let it go for many months (I've got a keg hitting the law this weekend that I filled in June). Maybe if I left it in the fermentor, not sure. Maybe I'll put the keg back to room temperature and leave it for another month and see what happens.
 
Is it possible that the second keg filled had a bunch of sediment (yeast and trub and crap) that the first did not have. Then maybe that keg had yeast autolysis which caused the soapiness in that keg?
 
petemoss said:
Is it possible that the second keg filled had a bunch of sediment (yeast and trub and crap) that the first did not have. Then maybe that keg had yeast autolysis which caused the soapiness in that keg?
Click to expand...

I'm very careful to keep stuff out of the keg. I get very little sediment in there (I usually leave close to a gallon in the fermentor just for this reason). I doubt that's the issue.

And I don't ferment long, so I doubt autolysis is the problem.
 
passedpawn said:
I'm very careful to keep stuff out of the keg. I get very little sediment in there (I usually leave close to a gallon in the fermentor just for this reason). I doubt that's the issue.

And I don't ferment long, so I doubt autolysis is the problem.
Click to expand...

Cool. Just thought I would ask. I am very interested to see what you find out.
 
Definitely try switching to a more pure cleaner. I buy sodium percarbonate and sodium metasilicate in bulk.

I've never had a soapy beer (though I've had soapy commercial beers, which I always assumed was autolysis).
 
In my opinion, not that it is worth much, but i have to say cleaning chemicals. From experience i use to buy soda from a town about 60 miles away, it always had a soapy taste in it. Had one the other day it still has the soapy taste. They get their water (as far as i know) from the same place, the Platte River wells.

I suggest doing another brew exact same equipment and cleaning methods and split the batch the same way. Mark the keg with the soapy taste beforehand and if you get a soapy taste again I suggest pour boiling bleach water in the keg and altering your cleaning methods and of course replacing all gaskets and o rings. If you don't have a straw brush get one and clean your pipes! Not like you are going on a first date but better, drain those things empty. You would be amazed at the stuff I was able to get out of mine after 10 years of brewing and just running water and sanitizer through them. Disassemble down to the nut.
Bed bath and beyond has one that is functional to 13.5 inches.
1565845810470264744325.jpg

Long enough to clean your tubes. It also comes in handy to clean picnic tap hoses, etc. Made my old hoses look new ish, definatly cleaned them out
 
Could be that in splitting, one batch got overpitched?
Quoting from Randy Mosher's "Tasting Beer"

Sensory Vocabulary
Autolysed
Type: Aroma, flavor
Descriptors: Autolysed, muddy, soy sauce, Marmite, umami, soap
Threshold in Beer: Varies Appropriateness: Generally not pleasant; acceptable in older, stronger beers Source: Various lipids and amino acids, the results of the disintegration of yeast cells
 
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I do a lot of reading on brewing subjects and I stumbled on an article about cleaning stainless steel kegs, fermentors, etc. to avoid beer stone and how the cleaners work best with each other. So for awhile now I soak fermentors and use my keg washer with PBW mixed with HOT water. Soak the fermentor and or use your keg washer as normal. The big thing is after you drain or dump the PBW the article recommended rinsing with HOT water. The HOT water rinse is very important after using PBW. After the rinse with HOT water, you then spray Star San out of a spray bottle on all the surfaces of the fermentor and or keg. Coating the surfaces with the Star San after a HOT PBW and a HOT water rinse prevents scaling and beer stone build up which is hard to clean off, which can otherwise leave residues inside the keg or fermentor. Then just store the keg or fermentor in this condition until you need to use it and then sanitize it before use. Maybe try this on that keg and see if the problem goes away. Good luck and post back if you find out what the cause is.

John
 
jcav said:
I do a lot of reading on brewing subjects and I stumbled on an article about cleaning stainless steel kegs, fermentors, etc. to avoid beer stone and how the cleaners work best with each other. So for awhile now I soak fermentors and use my keg washer with PBW mixed with HOT water. Soak the fermentor and or use your keg washer as normal. The big thing is after you drain or dump the PBW the article recommended rinsing with HOT water. The HOT water rinse is very important after using PBW. After the rinse with HOT water, you then spray Star San out of a spray bottle on all the surfaces of the fermentor and or keg. Coating the surfaces with the Star San after a HOT PBW and a HOT water rinse prevents scaling and beer stone build up which is hard to clean off, which can otherwise leave residues inside the keg or fermentor. Then just store the keg or fermentor in this condition until you need to use it and then sanitize it before use. Maybe try this on that keg and see if the problem goes away. Good luck and post back if you find out what the cause is.

John
Click to expand...
Yeah I noticed a huge reduction in deposits when I started doing a hot acid wash after the PBW.
I use citric acid.
 
passedpawn said:
PET (big mouth bubblers). I've got six of them, and they normally don't cause this, so not that.

I do use the normal oxyclean with the blue aromatic crystals. I rinse pretty good after a soak (I don't always do a soak though, only after IPAs). I'm going to switch to the "scent free" which is what I used to use a long time ago. Maybe I'm leaving one of those things in there, though I rinse upside down with a hose/sprayer so seems unlikely.

I store the fermentors with strong starsan solution, and only swish/dump before filling. I know starsan isn't a soap but an oxidative cleanser, so I don't really think that's the problem, BUT... the first time I ever had this flavor was after I had cold-crashed with a blowoff tube still connected, and the fermentor sucked back a bunch of starsan solution from the blowoff reservoir.
Click to expand...
I wonder for all the time you have already spent on this... maybe splurge for some PBW and use that in one control group? I mean (and i know i will get killed for this) using Oxyclean... i buy that in the "soap" aisle in the store... PBW aint cheap, but it does the job oh so well!
 
Nate R said:
I wonder for all the time you have already spent on this... maybe splurge for some PBW and use that in one control group? I mean (and i know i will get killed for this) using Oxyclean... i buy that in the "soap" aisle in the store... PBW aint cheap, but it does the job oh so well!
Click to expand...

Yes, you're right. I'm going to get some this weekend. It takes SO long to test out a hypothesis though, and note that the problem only appears occasionally.
 
passedpawn said:
Yes, you're right. I'm going to get some this weekend. It takes SO long to test out a hypothesis though, and note that the problem only appears occasionally.
Click to expand...
Yup. Could be months/ dozens of batches if you do it right.
But... i am shocked you did not start with pbw sooner, eslecially for a soap tatse.

Do you wash any of your regualt equipment in the dishwasher or with hand dishwashing soap? Spoons, paddles, etc.
 
Nate R said:
Yup. Could be months/ dozens of batches if you do it right.
But... i am shocked you did not start with pbw sooner, eslecially for a soap tatse.

Do you wash any of your regualt equipment in the dishwasher or with hand dishwashing soap? Spoons, paddles, etc.
Click to expand...

Nope. The only thing that gets oxyclean is the fermentors. They get rinsed well though.

Every few batches, especially after an IPA, I do a hot-soak of the boil kettle. I put a couple of scoops of oxyclean in there and heat to near boil. Hmmm. That SHOULD make both 5g batches bad (I do a single 10g and split) - but only one of them was bad this time. But it sure seems like the problem has to be that oxyclean.
 
passedpawn said:
Nope. The only thing that gets oxyclean is the fermentors. They get rinsed well though.

Every few batches, especially after an IPA, I do a hot-soak of the boil kettle. I put a couple of scoops of oxyclean in there and heat to near boil. Hmmm. That SHOULD make both 5g batches bad (I do a single 10g and split) - but only one of them was bad this time. But it sure seems like the problem has to be that oxyclean.
Click to expand...
I went down a rabbit hole here on the "oxyclean vs pbw" (or something like that) thread. Lots of people swear by the knoxk off brands from walmart or dollartree. (Sun brand? ) they get scent free.

But i dunno... after all the work in brewing and cost... pbw is pretty cheap really.
 
Despite it being a detergent there is no "soap" in oxyclean, either branded or no brand. There is no way any residue could be the cause for a soapy off-flavor.
 
petemoss said:
Is it possible that the second keg filled had a bunch of sediment (yeast and trub and crap) that the first did not have. Then maybe that keg had yeast autolysis which caused the soapiness in that keg?
Click to expand...

So I had one beer come out with a flavor that I described as soap/goat/coconut

It was a Boston Lager clone and yeast autolysis was my best guess as well, followed by an interplay between crystal malt and dry hop hopping with specific hops
 
Isn't StarSan's primary ingredient phosphoric acid, which is the same stuff they put in Cola as a flavouring thing? I doubt it'll be StarSan. It's an acidic base which is generally not linked to soapiness. Soapy flavours have always in my books been linked to alkaline solutions, so it might be something to look for.
 
Toxxyc said:
Isn't StarSan's primary ingredient phosphoric acid, which is the same stuff they put in Cola as a flavouring thing? I doubt it'll be StarSan. It's an acidic base which is generally not linked to soapiness. Soapy flavours have always in my books been linked to alkaline solutions, so it might be something to look for.
Click to expand...

Star san is tasteless in dilution. Taste some and see. I have. Star-san isn't the issue here.
 
Soapy will normally leave a soapy mark(s) on the glass. Seeing any?

Also, soapy will create rainbow colored bubbles. Seeing any?

I know these are out there, but just trying to help determine what might be causing the soapy and if it's really soap.
 
Tobor_8thMan said:
Soapy will normally leave a soapy mark(s) on the glass. Seeing any?

Also, soapy will create rainbow colored bubbles. Seeing any?
Click to expand...
No it won't. To taste it you don't need that much soap that you will be able to see it as well. Besides, if you have so much soap or oil that it can form a visible film on the beer's surface you'll also have no trace of foam whatsoever.
 
passedpawn said:
Beer looks totally normal otherwise. I think my process is fairly clean.

The fact that this last batch that I split AFTER the boil should be a big clue. Half of it is undrinkable, the other half was fine.
Click to expand...

If everything was the same except the fermenters and the kegs, there you are. As @Horseflesh says above, keep track of which are which, and see if it repeats itself.

Here's a possibility: When i use PBW, it doesn't always completely dissolve. I think there's a saturation point or something. It sits on the bottom of the kettle or tub I'm using. Suppose you have some of that oxyclean caked on somewhere in a fermenter (seems unlikely, I have Bigmouth Bubblers too), or in a keg? You might think it's all rinsed out, but it's sitting in a ridge or under the rim or inside your dip tube or maybe in the spigot if you have those....you get the point. I'd check the spigots first if you have them.

So it either has to be the fermenter or the keg. It's a huge clue. It also might not be the specific fermenter or keg that's at fault, but rather, how it happened to go down when cleaning those particular items. The next time, it might happen to a different fermenter or keg.
 
passedpawn is trying to determine the source of a soapy taste. One batch is fine and the other tastes soapy. I'm writing to consider tap lines, fermenters, etc. Something done to one and not the other. One was rinsed more than the other? Perhaps the glass had enough soap? Just throwing out ideas.
 
You don't by chance live with someone that is a practical joker do you. I could just see someone sneaking down to the basement late at night with some Dawn dish washing liquid.
 
If I missed this in your replies, I apologize.
Was one fermented longer or at different temp? Here is a "soapy" explanation straight from John Palmer.

"Soapy flavors can caused by not washing your glass very well, but they can also be produced by the fermentation conditions. If you leave the beer in the primary fermentor for a relatively long period of time after primary fermentation is over ("long" depends on the style and other fermentation factors), soapy flavors can result from the breakdown of fatty acids in the trub. Soap is, by definition, the salt of a fatty acid; so you are literally tasting soap."
 
I had one batch of soapy beer, luckily it did mellow with time to be drinkable but was always there to some extent if you looked for it. Initially it was very strong and did not take much of a sip to completely coat your mouth. That beer did not fully attenuate and there was quite of bit of yeast still in suspension on kegging so I am thinking it could of been a yeast related thing.

I use the unscented oxyclean(oxy-free?) and found I only need like barely enough to cover the bottom of the scoop (maybe 1/10th of a scoop)added to a 6 or 7gal fermentor to remove stuck on crap when I need to give it a soak. When I used more it seem to leave more of a film and took considerably more rinsing to get it off.

I am often amazed how much starsan (or water) clings to the sides of vessel when you a do a quick dump (looks empty) then reinvert. I get a slight tartness when I have tasted starsan and more of a puky flavor than soapy.
​
 

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