Glass Carboy Cleaning Incorrectly - possible source of off aroma

[RebelBrews]

Hi all. I recently started brewing again and I’d bought some glass carboys. I cleaned them like I always did by soaking them overnight with hot water and Oxiclean. Before the soak I had scrubbed a bit with the carboy brush and this time left the brush in the carboy overnight. Before draining I gave the carboy another brushing and then drained the water. I then rinsed the carboy a few times. It was then I noticed that there were lots of brush marks left on the inside of the carboy. These brush marks are difficult but not impossible to remove. Though a few areas do seem particularly stubborn. I don’t think they’re regular brewing residues as they seem very white.

After some research I discovered that using hot water to clean glass carboys is actually quite dangerous because of the thermal stress on the glass. So I won’t be doing it again. However, my main question is about what I should do now. I’ve removed about 95% of the marks and rinsed it a bunch. Ditching the carboy would be less expensive to me than wasting my next batch.

This whole situation reminded me of a frustrating problem I’d had in my previous brewing life. I went through a streak of beer batches that had an off aroma and I’d convinced myself it was caused by chlorophenols from chloramine in the water supply. It seemed impossible to resolve even with careful treatment of the water. However, now I’m wondering if leaving a carboy brush in super hot water might soften the plastic bristles enough to leave plastic residue behind and even possibly have been the source of the burnt plastic phenolics I’d previously encountered many years ago.

Questions:

1. Should I ditch the glass carboy?

2. Is the carboy brush left in hot water a possible/likely source of band-aid like phenolics?

Any help would be appreciated. Thanks!

 

[IslandLizard]

Glass itself is very impermeable. I seriously doubt any flavors, including plastic-like ones, if they so happened, will be picked up.

If there's no residue, goo, patches of who knows what on the inside, left, the carboy should be clean and sanitizable. A little Bar Keepers Friend (BKF) scouring powder may be needed to remove stubborn patches that don't look clean to you. A piece of rag around the bristles give you a bit more surface friction and grip. Could also be from a dirty mould during manufacturing... Nothing will remove those, it's baked into the glass.

Using very hot water in a glass carboy won't be good, thermal stress, thermal shock.
But warm, tepid water should be fine, unless you just retrieved the carboy from a -30F snow bank. Thermal differences can crack the glass. So can bumps, and weight when full.

Are these brand new or older carboys?

Handling large glass vessels like that remains dangerous, especially when quality control during manufacturing is poor or non-existent.
Many (glass) carboys, sold nowadays and over the past 10 years, have been found (after breaking) with areas where the walls are paper thin, under 1/16"! So be warned and please, be extremely careful handling them!

There are many plastic fermenter alternatives! Even Stainless ones.

If you brewing water is municipal tap water it will contain chlorine or chloramines. You need to remove those by treating with 1/4 Campden tablet or a good pinch of K-Meta per 5 gallons. Not removing them can cause Bandaid off-flavors.

 

[RebelBrews]

I definitely appreciate your thorough and informative response. It may have indeed been better to go with the plastic carboys this time around. I just like the way that glass looks. Definitely hear you on the extreme temperature differential being the key thing to avoid.

I don’t think the majority of the marks I’ve found were there from the manufacturer though certainly some of them could be. Most of the marks I found really did resemble little white scratches spaced much like the bristles of the brush.

One of my glass carboys was manufactured in Italy and the other, who knows. I’ll certainly heed your advice regarding limiting the temps to tepid water and, in general, being extraordinarily cautious in handling the glass carboys.

Thanks again and cheers!


PS - Forgot to mention that after my previous encounter with phenols I definitely use campden tablets whenever I brew with tap water. It’s good advice nonetheless. I think I had a couple phenolic batches even after using campden but it’s been so long it’s hard to remember for sure. No phenolics this time around but the leftover marks got me thinking.

 

[Gruel]

My understanding is that oxiclean (name not withstanding) is not used for cleaning brewing/fermenting residue, but for sanitizing. So your carboy might be due for a hot alkali bath and a good scrubbing...

 

[jschein]

Oxiclean does not sanitize it is a cleaner only

 

[RebelBrews]

My understanding is that oxiclean (name not withstanding) is not used for cleaning brewing/fermenting residue, but for sanitizing. So your carboy might be due for a hot alkali bath and a good scrubbing...

It’s definitely meant for cleaning and it’s always been great in the past.

Though you bring up a really interesting idea in that there might be a chemistry solution.

 

[Gruel]

Interesting.

Rebelbrews, I think that for 'sanitizability' you are better off with glass than with plastic.
In any case, it sounds like you need both an acidic and an alkaline cleaner to remove beer stone:
https://www.morebeer.com/articles/removing_preventing_beerstoneAlso, shout (added: oxy power) seems to be better than oxiclean (higher H2O2 content) for sanitizing: http://www.umich.edu/~chemstu/conte...pics_notes/Bracken_JCE_2005_p762_oxyclean.pdf

 

[jschein]

Interesting.

Rebelbrews, I think that for 'sanitizability' you are better of with glass than with plastic.
In any case, it sounds like you need both an acidic and an alkaline cleaner to remove beer stone:
https://www.morebeer.com/articles/removing_preventing_beerstoneAlso, shout seems to be better than oxiclean (higher H2O2 content) for sanitizing: http://www.umich.edu/~chemstu/conte...pics_notes/Bracken_JCE_2005_p762_oxyclean.pdf

I really don’t think Shout should be used either , I am no scientist but doesn’t sound right

 

[IslandLizard]

One of my glass carboys was manufactured in Italy and the other, who knows.

Glass carboys from Italy are supposed to be good. They're ribbed and cylindrically shaped. The name "Italy" only sometimes visibly cast into the bottom, IIRC.

Glass carboys from Mexico, at least those from until 2010 are solid and good too. They are smooth, not ribbed, traditional carboy shape, with a distinct shoulder. Not sure about the country name or some ID always appearing either.
Somewhere in 2009 Mexican carboys started to disappear from the U.S. market. The ribbed Italian ones became more commonly available, taking their place.

Within 2 years after the demise of Mexican carboys, glass carboys from China (no name or ID) started to flood the markets everywhere, looking just like the Italian ones (ribbed, cylindrical). They brought big problems with them due to poor manufacturing standards, lack of adequate testing/QC/oversight, you name it. Razor thin walls in random areas, in the smooth rectangular sections between the ribs. With those the bottom also tended to sheer off for no apparent reason. Nice, huh?
The glass Wide (Big?) Mouth Bubblers from NB also came from China, with the same flaws.

I still have a bunch of glass carboys, mostly from Italy and Mexico, AFAIK, but they only get used for long term aging, like sours, so they are handled minimally, not routinely for monthly batches.

 

[day_trippr]

Oxyclean is notorious for leaving a white film behind when left in glass for a protracted period, especially with high RA water (lots of carbonates 'n' stuff to precipitate out). But you can almost always remove that white film just using a household acid like white vinegar - no scrubbing/brushing required, just swirl high strength vinegar around and it'll cut that residue right off.

Thermal stress of carboys is to be avoided like...the current plague. That means not only avoiding applying hot water to, say, room temperature glass, it also means not rinsing out a cold-crashed carboy right after racking to a keg or bottling bucket - even your coldest household water may well be 30-40°F warmer than that carboy, and that's a huge thermal shock.

I have done all of my brewing in the same six 6.5 gallon italian glass for 15 years and treat them like eggs loaded with tiny nukes I always try to keep temperature differentials under 5°F at any stage of brewing and cleaning, which often means letting them sit for a few hours to slowly warm up, and never using anything approaching "hot" for cleaning...

Cheers!

 

[IslandLizard]

For better cleaning action, you can also add some TSP or TSP/90 to your Oxiclean, effectively creating homemade PBW (70% Oxiclean free + 30% TSP/90).

But don't let the "PBW" sit in glass forever, like more than 48 hours. it may leave a white residue over longer time. You can recapture the PBW solution if it's still clean and reuse later. Store in a small plastic bucket or plastic jug, but keep the lid on slightly loose, so it can vent any O2 that dissipates. It loses the oxygen component over time, but it's still a good allround brewery equipment cleaner.

Warmer works better/faster, but use common sense in combination with glass carboys.

 

[RebelBrews]

Within 2 years after the demise of Mexican carboys, glass carboys from China (no name or ID) started to flood the markets everywhere, looking just like the Italian ones (ribbed, cylindrical). They brought big problems with them due to poor manufacturing standards, lack of adequate testing/QC/oversight, you name it. Razor thin walls in random areas, in the smooth rectangular sections between the ribs. With those the bottom also tended to sheer off for no apparent reason. Nice, huh?

Nice and moderately terrifying!

I have one glass carboy from Italy, one from Mexico, and one with no stamp which looks like the Italian one (ribbed). I’m relegating this third, possible Chinese, carboy to emergency usage only.

I’m going to try to the added TSP you mentioned with the Oxiclean Free. This, and PBW generally, seem like good next research topics in my brewing education.

Thanks again for all your help andvaluable info!

 

[RebelBrews]

Oxyclean is notorious for leaving a white film behind when left in glass for a protracted period, especially with high RA water (lots of carbonates 'n' stuff to precipitate out). But you can almost always remove that white film just using a household acid like white vinegar - no scrubbing/brushing required, just swirl high strength vinegar around and it'll cut that residue right off.

I’ll try this in the morning. Seems very possible that this is what’s going on since I’ve moved to a different location with possibly “high RA water“.

I have done all of my brewing in the same six 6.5 gallon italian glass for 15 years and treat them like eggs loaded with tiny nukes I always try to keep temperature differentials under 5°F at any stage of brewing and cleaning, which often means letting them sit for a few hours to slowly warm up, and never using anything approaching "hot" for cleaning...

Certainly sage advice that I will keep in mind. I think I’ve been reasonably careful with my carboys but perhaps I need to go full on “eggs loaded with nukes” level.

I appreciate the help! ✌

 

[Beermeister32]

Oxyclean Free can leave a white alkaline film on the inside of the carboy. Usually thorough brushing removes this. You may have left brush marks on this residue. After soaking in Oxyclean Free for a couple days, scrubbing and rinsing, I then fill the carboy with a Star-San solution. The acidity of the Star-San will break up any remaining alkaline residue you may have missed. Also if you leave the Oxyclean Free in too long, you can get some re-crystalization of the materials in the bottom of the carboy. This can also be dissolved using the follow-up Star-San soak. Do a final scrub and rinse of the Star-San and the carboys should be good to go for use or drying for storage.

I moved from plastic carboys to glass, and then back to plastic. I moved to the glass because I figured this would provide the best beer. After looking at all the potential hand slices and damage people were suffering from broken carboys, I ended up discarding them for safety reasons. They also add considerable weight when you are lugging them around full, so to minimize back issues, I ended up back to plastic carboys.

 

[Hwk-I-St8]

As a guitar player I didn't want to risk messing with glass. I've had an assortment of hand injuries over the years and I can say this: playing a 4 hour gig with a cut on your finger sucks royally and people look at you weird when there's blood dripping off your guitar neck. I quickly learned to wear gloves when loading in/out for shows.

I use PET Big Mouth Bubblers and I really like 'em. I only do primary fermentation for 95% of my beers. Anything I want to do extended fermentation and/or bulk aging gets racked to a corny with a spunding valve. That's stainless steel (of course), so definitely suitable for long term storage. It's easy to purge O2 and I can draw off samples easily. My primary usage for that is for high gravity stouts that I want to pseudo barral age with oak staves.

I got some glass carboys with the bundle of brewing equipment I got used when I got back into all grain, but I gave 'em all away.

 

[RebelBrews]

I wanted to report back after using the vinegar. This definitely seems to have done the trick. The glass now seems perfectly clear and not a single mark remains! I’ve got to believe it was some form of mineral deposits that formed in about 12 hours. So I’d bet that pretty much any acid solution (like Star-San, as was also suggested) would have resolved the problem.

Anyway, maybe that’ll help some folks who have a similar problem in the future.

Thanks to all who chimed in trying to help out!

 

[Bramling Cross]

Rebel, I brewed for over 25 years in two 6.5 gallon carboys. I briefly tried Oxyclean during that time and like you and the others, I found that white film and undissolved blobs of the material tended to stick fast to both carboys' surfaces. The following is a process that I settled on pretty early. During that time I tried numerous other processes, but kept coming back to the following process because it fits very well with my diligent commitment to maximum laziness.

Allow me a quick author's preemptive strike: this process uses bleach, a material that makes many brewers recoil in horror. Some of that horror is irrational, but there's good reason to tread carefully when using bleach in your brewery. If you treat it with the respect it requires, it's very useful stuff. If you get sloppy and try to cut corners, it will punish you. Fortunately, as a certified common idiot, I can confidently report that a common idiot was able to use this process for a couple of decades without damaging any beer.

First, never store your carboys dry. Dry things are hard to clean and hard to clean things require scrubbing, a form of work that should be avoided whenever possible. As such, once you're finished siphoning out of your carboy, rinse it thoroughly, add a pint of bleach, then fill the carboy to the brim and cap it. You can now place your dirty, un-scrubbed carboy in storage.

When you're ready to brew again, you'll be delighted to find that your filthy carboy is now magically clean. All that nasty brown stuff that was stuck to the walls of the carboy has turned white and has fallen to the bottom of the carboy and formed a fluffy white layer that is very easy to rinse out. Some especially tenacious material my require a quick wipe with a carboy brush, but no scrubbing will be necessary. Go ahead and drain the carboy and rinse it thoroughly three times. Bleach must be respected, so take your time and make certain that you've rinsed and drained the carboy thoroughly. Once that's done, you can deploy your sanitizer of choice and it's business as usual.

A nice knock on effect of this process is the confidence of mind that you get from knowing that your carboy has been comprehensively nuked between cycles.

I hope you found this useful, Rebel. I know bleach makes folks pretty nervous, but this is the process that I kept coming back to over the years. It seems to provide the most thorough cleaning for the least amount of work.

 

[RebelBrews]

playing a 4 hour gig with a cut on your finger sucks royally and people look at you weird when there's blood dripping off your guitar neck.

I’m going to take a wild guess and say that you’re were not playing death metal as the blood on the guitar might’ve then been a bonus!

I’m seriously considering a PET carboy for most of my beers.

Thanks for your comment.

 

[RebelBrews]

once you're finished siphoning out of your carboy, rinse it thoroughly, add a pint of bleach, then fill the carboy to the brim and cap it. You can now place your dirty, un-scrubbed carboy in storage.

When you're ready to brew again, you'll be delighted to find that your filthy carboy is now magically clean.

This certainly seems like a good and efficient way to do it. As a brewer who’s had a few batches ruined by chlorine’s malignant cousin, chloramine, I am extra nervous about using chlorine in the process. However, considering that I am also quite committed to maximum laziness, it is definitely worth considering your methods. I do understand that there’s a science to it and that by following certain protocols it is safe to use chlorine. Also, I’m quite confident in my ability to perform at a common idiot level, at the minimum. I’ve definitely had a few brushes with total idiocy in my life but thankfully they are exceedingly rare.

I did find your post helpful and I think I’ll try the chlorine method, as you’ve outlined it, on my next batch to be racked out of the Italian glass carboy. It’s a dark porter with a substantial krausen ring so it’ll definitely be a good test.

 

[Bramling Cross]

This certainly seems like a good and efficient way to do it. As a brewer who’s had a few batches ruined by chlorine’s malignant cousin, chloramine, I am extra nervous about using chlorine in the process. However, considering that I am also quite committed to maximum laziness, it is definitely worth considering your methods. I do understand that there’s a science to it and that by following certain protocols it is safe to use chlorine. Also, I’m quite confident in my ability to perform at a common idiot level, at the minimum. I’ve definitely had a few brushes with total idiocy in my life but thankfully they are exceedingly rare.

I did find your post helpful and I think I’ll try the chlorine method, as you’ve outlined it, on my next batch to be racked out of the Italian glass carboy. It’s a dark porter with a substantial krausen ring so it’ll definitely be a good test.

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I'm happy to hear you found my ramblings useful. I'll bet if you let that ring soak for two weeks, it'll disappear. One week may require a bit of light wiping with the brush. So long as you rinse and drain it three times, you'll do great!

That's a fine looking porter, I'm jealous.

 

[IslandLizard]

add a pint of bleach, then fill the carboy to the brim and cap it.

A pint of bleach sounds like a real lot. I was more thinking along a cup perhaps.

I'm with you on not letting dirty fermenters sit dry. But clean and sanitized ones may dry up IMO.
I sometimes leave an inch (or 2) of Starsan in carboys and give them a shake from time to time. The carboys get their mouths covered with plastic wrap.

 

[ncbrewer]

Allow me a quick author's preemptive strike: this process uses bleach, a material that makes many brewers recoil in horror. Some of that horror is irrational, but there's good reason to tread carefully when using bleach in your brewery. If you treat it with the respect it requires, it's very useful stuff.

In the past, I was strongly opposed to using bleach, but for the last couple of years I've been using bleach to clean bottles after pouring. Bleach, without any scrubbing, seems to do a better job than OxiClean with scrubbing. Papazian's Complete Joy of Home Brewing recommends 2 oz bleach in 5 gallons and an overnight soak when used as a cleaner. I use double that concentration to allow for the bleach possibly being old. Papazian calls for a warm or hot water rinse, so I'm not sure how I would feel about using it for a glass carboy. How warm do you feel is safe with a carboy?

 

[ncbrewer]

I did find your post helpful and I think I’ll try the chlorine method, as you’ve outlined it, on my next batch to be racked out of the Italian glass carboy. It’s a dark porter with a substantial krausen ring so it’ll definitely be a good test.

In case you're not aware, the carboy carrying handle is for empty carboys only.

 

[Beermeister32]

It is important to note that if you must use bleach, you must limit the soak to glass carboys and not plastic. Some plastics could conceivably pick up a bleach odor which could permeate the beer. Also important, bleach can not be kept long term within stainless steel which it will corrode, causing pitting and holes. This means glass only, no corny kegs or other brewing gear.

Rather than bleach, I store my cleaned corny kegs with a Star-San solution, then I use the same batch to fill a 5 gallon bucket as sanitizer for bottling. Make sure to slightly pressurize with C02 to set the O-rings. Works great.

 

[Deadalus]

I highly recommend building yourself a carboy/keg washer, so much easier. After transfer, I will blast the carboy using a bottle rinser I have on a second faucet on my utility sink. Very important to do right away and not let sit. (Okay sometimes I do let it sit after the rinse and even before). Then it goes on the carboy washer, which in most cases I end up leaving overnight with a weaker solution of homemade PBW, one scoop in about 2.5-3.0 gallons (keeps foaming down). Then the carboy gets the outside cleaned with a rag and some Dawn in the sink. Outside is washed down, then rinsed again with the bottle washer. I toss in a gallon of Starsan solution, sanitize, then upside down it dries in a carboy stand. When it's dry, I slap on a piece of aluminum foil and it gets stored in a rack. Most times I save/reuse the Starsan for other cleaning. Brew day just for peace of mind I run another gallon of Starsan solution through the carboy before transfer out of the BK. I don't really even use the brush anymore.

I run a vinegar solution through the washer every couple of runs to keep it shiny.