Plastic Carboys. Good or Bad?

[brewgineers]

Personally I only use food grade white plastic for my fermenting. But have come across a bunch of plastic water jugs exactly like the glass carboys just plastic. Do you think that the plastic carboys are a good idea or is the plastic so different it wouldn't work properly?

 

[godofcheese]

I use a plastic carboy with no problems. I have one that I use for sour beers exclusively now.

Some people say the water jug ones are too thin and allow air to permeate them, but I don't know. I don't see how that could happen.

 

[HexKrak]

From past threads on the subject it seems that the consensus is, only food grade plastics labeled type 1 or type 2 are best used for fermenting beer. However many people have used the typical water bottles labeled type 7 with no ill effects.

Here's one of the many threads, for reference. https://www.homebrewtalk.com/f11/better-bottle-plastic-water-cooler-bottle-99933/

 

[HexKrak]

Some people say the water jug ones are too thin and allow air to permeate them, but I don't know. I don't see how that could happen.

It's not about them being thin, it's a different grade of plastic. You know how a helium filled balloon eventually stops floating? It's because even though the gas inside is sealed with the knot, the helium is able to slowly permeate through the rubber. It's similar with the water bottles. Even though they're "air tight" oxygen may be able to permeate the plastic anyway.

 

[brewgineers]

Gotcha think i may pass on getting the plastic carboys and stick with food grade buckets. thanks for the info

 

[JJL]

There's really no harm in using a plastic better bottle style carboy. There's also no harm in using a plastic bucket. They both work just fine. It just depends on what your individual needs are. You just need something that's going to keep air out and isn't going to put anything undesirable into your beer.

 

[Bottenbrew]

Keep in mind that in chemistry labs plastic drink bottles are usually banned, because chemicals can go through them leading to interesting and potentially deadly consequences. Not as big of a deal in a home brewing setting, but things will get in/out.

 

[RM-MN]

How long would you leave the beer in them? A week, a month, a year, a decade? Yes oxygen may be able to permeate the plastic and affect your beer but it isn't instantaneous. It takes time to get enough oxygen to affect your beer to the point that you can taste it. I only leave my beer for a couple of weeks to clear or to ferment fruits and haven't noticed any off flavor. Maybe I have poor sense of taste?

 

[jfr1111]

To me, glass carboys are a necessary evil for certain purposes (namely aging). Plastic carboy would seem to add all the disadvantages of glass carboys (difficult to clean, clunky) and plastic buckets (can scratch easily). You can use them fine, but what advantage would they have over your basic plastic bucket ?

 

[ReverseApacheMaster]

To me, glass carboys are a necessary evil for certain purposes (namely aging). Plastic carboy would seem to add all the disadvantages of glass carboys (difficult to clean, clunky) and plastic buckets (can scratch easily). You can use them fine, but what advantage would they have over your basic plastic bucket ?

You can see through them. They are cheaper than glass. Better Bottles and similar plastic carboys are PET rather than HDPE so they let in significantly less oxygen. Although that may not be significant for beers that get a few months in the fermenter, that's going to be too much oxygen for long term aging.

 

[passedpawn]

I vaguely remember this being brought up sometime in the past. Maybe a search will produce good results. Try "glass vs. plastic".

 

[gicts]

It's not about them being thin, it's a different grade of plastic. You know how a helium filled balloon eventually stops floating? It's because even though the gas inside is sealed with the knot, the helium is able to slowly permeate through the rubber. It's similar with the water bottles. Even though they're "air tight" oxygen may be able to permeate the plastic anyway.

Fantastic analogy! For short term storage I'd use them. To the OP: My question is why do you need them for beer? Microbreweries tend to use stainless steel, BTW.

 

[bigc3031]

I always see these debates and have wondered why no one sells a stainless carboy?

 

[Crimsonwine]

What about beer aged in casks? I would not exactly think those have a oxygen barrier...and I am sure water manufacturers that use plastic bottles don't want off flavors too...I am sure they plan on water being stored for a month or more before being used...and they recycle them....so why wouldn't they work for beer?

As for breweries using stainless steel I think it has to do with economies of scale....easy to build a huge tank out of stainless than fabricate a plastic or glass one, stainless is more durable ...plus I have to think plastic breaks down after a while, harder to clean over time...Not to mention replacing huge tanks...It seems they have to make an opening in the roof or wall just to move them in or out...

On a homebrew scale plastic and glass is just more easier to work with, less expensive to deal with and can be easily replaced....not to mention manufacturers target accessories for plastic buckets and carboys so it's more available and less expensive to buy them...

Just my .02....

 

[jfr1111]

You can see through them.

This gets quoted a lot and I'm not sure what the advantage is. The first batch or so, looking at the beer is nice, but afterwards ? You can also open a bucket if you really need to sneak a peak. I guess I'm not mesmerized by fermentation.

Better Bottles are an entirely different animal in my mind than what OP was referring to. I associate the plastic carboys with the flimsy, paper thin, off-white cheapos (so no seeing the beer) that wine stores carry for 10 bucks a piece. They all seem to have ridges inside of them to make cleaning more difficult than necessary.

 

[IffyG]

I always see these debates and have wondered why no one sells a stainless carboy?

Price....

 

[bovineblitz]

I sometimes use a #1 plastic PET office water jug for fermentation. Haven't had any issues yet keeping brews in it for about a month, I plan on using it exclusively for sours in the near future.

 

[ILuvIPA]

Price....

I always see these debates and have wondered why no one sells a stainless carboy?

hmm. . .I have a thin wall 5 gallon pot picked up from a garage sale last summer. I've been using it to heat mash/sparge water. Might throw next month's barley wine in for the ferment. Thanks bigC

 

[fatguy-littlecoat]

This gets quoted a lot and I'm not sure what the advantage is. The first batch or so, looking at the beer is nice, but afterwards ? You can also open a bucket if you really need to sneak a peak. I guess I'm not mesmerized by fermentation.

being able to look at my krausen to see when it starts and when it falls is a big advantage. it takes quite a bit to open the buckets i have, not exactly easy.

 

[Calder]

Plastic is OK for short-term storage. Say about a month .... 2, 3, who's to say. If it produces good beer, then keep using it.

Plastic does let more oxygen in than glass, so long-term storage in plastic will allow more oxygen in to spoil the beer than a glass carboy.

Better bottles are supposed to be a superior type of plastic which lets in less oxygen than other fermenters.

Personally; for beers that go from the kettle to the bottle in a month or less, it doen't matter what they are fermented in as long as it's food grade.

For long term storage, it is a different matter. Doing a Lambic or Brett that will be in the carboy for a year or more, it might make a difference. From 'Wild Brews' (an excellent book by the way):

Large wooden barrel (Rodenbach) allows in about 0.75 ccs/L/year of Oxygen.
5 gallon glass carboy allows in 17 ccs/L/year of Oxygen (through a silicone stopper).
5 gallon HPDE bucket (I assume a sealed HPDE fermenter) allows 220 ccs/L/year of Oxygen.

Roughly 10 times the oxygen gets to the beer with plastic vs glass. Does it make a difference ........ that's the $64 million question. Me; I'm sticking with glass for anything I plan to age.

Someone commented that wood barrels let in a lot of oxygen. That's correct, but the barrels they use are very large (thousands of gallons), the the surface area to volume is very low, resulting in a low amount of oxygen compared to the overall volume.

 

[bigc3031]

I would love to see a 6 gallon stainless Carboy with a top similar to the blichmann conical to allow easy additions like fruits or woods during fermentation. The time savings for cleaning would be worth the price.

 

[92greenyj]

i seem to recall part of the issue with the 5 gallon water jugs being that they are just 5 gallons. I.E. not having enough space to allow proper fermentation of a 5 gallon batch. i know that has been brought up before in these threads

 

[bovineblitz]

i seem to recall part of the issue with the 5 gallon water jugs being that they are just 5 gallons. I.E. not having enough space to allow proper fermentation of a 5 gallon batch. i know that has been brought up before in these threads

True. You can use them for secondary. Sometimes I brew 4.5 gallon batches to fit them in 5gal carboys for primary. With fermcap you only need a half gallon of headspace.

 

[rodneypierce]

i just snagged one from the water bottle at work. It is a culligan bottle, but its a 1, PET bottle. Its getting an oxyclean soak right now, and then I will clean it out really good. Looking forward to actually being able to see the fermentation take place!!!

 

[92greenyj]

True. You can use them for secondary. Sometimes I brew 4.5 gallon batches to fit them in 5gal carboys for primary. With fermcap you only need a half gallon of headspace.

thought that had come up before.

Still, i think its more of a hassle then its worth. I do all my fermenting, both primary and secondary in the standard 6.5 gallon plastic bucket with a spigot installed for easy transferring. I have 1 6.5 gal glass carboy that gets used only if i want a long secondary on a big beer (imperial whatever, barley wine, etc) I'd rather use the buckets with the spigots. makes transfering way easier

 

[cheezydemon3]

From past threads on the subject it seems that the consensus is, only food grade plastics labeled type 1 or type 2 are best used for fermenting beer. However many people have used the typical water bottles labeled type 7 with no ill effects.

Here's one of the many threads, for reference. https://www.homebrewtalk.com/f11/better-bottle-plastic-water-cooler-bottle-99933/

5 is OK too 7 is NOT. Buckets are the best, but I do own 1 better bottle.

Gotcha think i may pass on getting the plastic carboys and stick with food grade buckets. thanks for the info

Food grade bottles are OK (like the BB) but water cooler bottles are off limits.

"no adverse effects"?

How would one measure BPA or whatever taken in through a batch of beer?

 

[AsbestosBike]

Does anybody know if you could use the 5 gallon water jugs they sell at grocery stores? They are really built solid and durable and I am on a budget and don't want to spend lots of money on a glass one. Would these work well for brewing? They only cost about $10!

 

[rodneypierce]

you will get all sorts of answers here. My suggestion, try it and make your own opinion. The batch I just bottled, sat in a culligan "off limits according to some" store bought water bottle for 3 months. Guess what? Its an absolutely amazing beer! Doesnt taste like vinegar, or any of the other horror stories you hear. I have another batch down in the basement right now, in another culligan bottle. Been there for 2 months. I bet money it will be just as great as the last batch! Try it out on your own and form your own opinions. thats my suggestion.

 

[AsbestosBike]

Thanks rodneypierce, I'm going to try it......hey, it comes with free water too, so why not right?!