Are Plastic Carboys A Problem??

It think you should be more concerned in your choice of air-lock/stopper material than the plastic carboy. People use plastic carboys (Better Bottles), for long term aging, all the time with no ill effects. I would advise against using traditional air locks or silicone bungs however...see study here:

http://www.mocon.com/pdf/optech/Closures - Oxygen Passage Study.pdf

 

buckets have been used since modern homebrewers have been brewing.
buckets are fine for brewing. there is some belief that because they can scratch and permit bugs to hide there is a contamination risk, but this is not a real problem among homebrewers. buckets can be sanitized effectively.

for a secondary, extended aging, then you do want to use glass. the reason has more to do with the surface area of exposed beer. there is a lot of surface in a bucket, no matter what. but you can fill a glass carboy right up to the top of the shoulders and reduce the surface area to only an inch or two.

as for the oxygen permeability of plastic, yes plastic is undoubtedly more permeable than glass. glass is impermeable. plastic is not. however, we don't hear about too many people complaining that their plastic bucket leached oxygen. I don't think it is a risk, but im not John Palmer, so take it for what its worth.
Cheers.

 

Staling from oxygen permeation in better bottles from my experience is no more than a myth. I have kept multiple beers in better bottles for 6-15 months with zero signs of oxidation. Just be smart about how you handle the beers and how often you taste/test them and you will be fine.

 

Palmer's comments address the type of plastic used in ale buckets.

The Bubbler® plastic is not the same plastic used in ale buckets.
The plastic used in ale buckets permeates more O2 than the Bubbler® plastic.

 

Buckets and the old type of plastic carboy (i.e. water cooler jugs) are made of HDPE, which is fine for short term storage, but it's too oxygen permeable for long term storage. Modern plastic carboys like the "Better Bottle" and the "Bubbler" are made of PET, which is less oxygen permeable and is suitable for long term storage.

 

You should consider skipping a secondary. Many of us (most?) only find value in them for certain beers like lagers and sours that require longterm aging, or perhaps fruit beets that have additional periods of actual fermentation. If you are going to do an extended secondary, you should avoid plastic.

 

Man some people worry about the little stuff too much. Relax have a home brew.

 

Carboys, cowboys and airlocks, I don't trust them. I have 4 buckets and one carboy for seconderey .
Alleyways use gravity reading rather then airlock. Brewing Software will get you

 

Don't plastic carboys get scratched and thus are harder to clean and sterilize?

 

Only if you scour them with a carboy brush or something. A little PBW soak and rinse, and there should be no potential for scratches. Not to mention nothing on a homebrew scale is ever sterilized, unless you autoclave your equipment or something. Sanitized is all that is really needed.

 

my issues with plastic:

1. you have to be sure that it is food-grade plastic
2. i would not do MOST long-aged beer in them, including sours with fruit additions for multiple months and where pediococcus is part of the bug mix. i'd be worried about too much tartness. the oxygen permeability is much greater than glass. not sure if it is practically significant or just statistically significant, but why risk it
3. i'd use a bucket for fruit additions for 1-2 months. no data behind it, just brain perception
4. i'd use it for any type of sacch brew
5. i am currently using it for a lambic. kind of seems to contradict what i posted above about bug mixes, but if you think of how lambics are made (in wood barrels in non-climatized settings), then plastic is actually likely a better bet for genuine results vs glass
6. plastic buckets tend to retain beer smells. I've soaked mine in oxyclean after. some still smell like cider or the sour that i had in them. and that scares me a bit.