Old PETs. End of life, or temporary blip?

[Marty_G]

16 minutes ago, ChristinaS1 said:

All plastics are porous. PET is one of the better ones, although PET is better at blocking CO2 (larger molecule) than O2.  Beer is very sensitive to staling from oxygen, more so than soda is. If you Google it there are many possibly links, albeit most are from the plastics and recycling industries.

They are working on technology to improve PET bottles with various liners, impregnating the resin with oxygen scavengers, and UV blockers....Soft drinks bottles are ordinary PET.

One issue is that amber PET is it difficult to recycle. Recyclers don't make much money on coloured PET. They prefer clear or light blue.

Another possible issue is that PET is not heat stable. It can leach a chemical called antimony into water or beer that is stored at temperatures of 60C or higher, such in an enclosed shed or car.

https://www.ncbi.nlm.nih.gov/pubmed/17707454

Cheers,

Christina.

Thanks, I was aware of the heat stability issues ... that is why commercially brewed beer is not in PET because of the pasteurisation temp and instability ...  thanks for the links i had already done a cursory search on Google but not found articles that had satisfied me .... I hate reading stuff that is more prose than fact ...  cheers 

[ChristinaS1]

30 minutes ago, MartyG1525230263 said:

Thanks, I was aware of the heat stability issues ... that is why commercially brewed beer is not in PET because of the pasteurisation temp and instability ...  thanks for the links i had already done a cursory search on Google but not found articles that had satisfied me .... I hate reading stuff that is more prose than fact ...  cheers 

Yes, PET bottles are not compatible with common bottle pasteurization, although some breweries (like Anchor) pasteurize before bottling and still don't use PET.

https://www.anchorbrewing.com/blog/ask-bob-brewer-pasteurizing-craft-beer/

[alexhenderson]

On 3/27/2019 at 6:27 PM, Worthog said:

I've been saying on here that I'm moving to All-Glass as bottling receptacles.

I'm there now, I've only needed 4 weeks of finished goods inventory to keep me happy "as a Worthog in mud", over summer.

Over the last 2 months I have changed from Carb Drops to a measured Dextrose carbonation regime.

I have found the reducing number of PET bottles in inventory are lacking carbonation compared to the glass longnecks of the same batches, all of which are sub 4 weeks bottled.

The question is;

• Are my ageing PETS, 10-15 cycles, finding their limit (always new caps)?
• Has it got something to do with Dextrose carbonation?
• Is it that nightime ambient carbonation temps are getting to low teens here in NE Victoria?

Thoughts and Cheers

I have been filling some PET bottles today, three leaked as I was filling them, I think they are at the end of their life, two were of the same type, I am gradually changing over to water bottles but I have over three hundred of these pesky PETs. 

[Worthog]

Yeah, the problem is that you can't know if they are end-of-life until they begin failing, either catastrophically as in your case, or worse, you find a percentage of your batch dead. This begins to get expensive and frustrating.

Mine had completed 10-15 cycles. Maybe people should manage their PETs to be replaced at, say, 10 cycles.

Anyway, I am now 100% glass.

Cheers

[Marty_G]

Interesting experiment yesterday, the last 2 bottles of a batch of cider i made the wife 1 a PET and the other a coopers   .... opened a Cooper tallie to drink and the to use in a slow cooked 2 kg piece of pork ... the class tasted completely different to the PET ... the PET had a slightly different colour but was bitter or dryer the glass crisp clean and sweeter ... 

[Pezzza]

On 4/7/2019 at 10:28 AM, ChristinaS1 said:

... some breweries (like Anchor) pasteurize before bottling and still don't use PET.

 

Is that the brewery of the legendary San Fran Anchor Steam?

Has that some connexion to what is known as Dampf Bier (John from P911 had mentioned re potential for wheat beer yeast in an ale if I remember rightly?)

[Pezzza]

On 4/15/2019 at 12:36 PM, Worthog said:

I am now 100% glass

... besides glass in eyes issue mentioned on the Forum... believe glass is good when it comes to bottles.

And I guess we need to brew to avoid explosions and in any danger... guess open w safety glasses?

[Worthog]

4 minutes ago, Bearded Burbler said:

... besides glass in eyes issue mentioned on the Forum... believe glass is good when it comes to bottles.

And I guess we need to brew to avoid explosions and in any danger... guess open w safety glasses?

You could go stainless steel - kegs - but I'm sure there are safety issues with that process also.

It gets back to one's responsibility to work through a safe environment. If your research, training and knowledge of a process is so poor that you can't keep surrounding people safe, then one should reconsider what one is doing.

A great starting point for new brewers is to learn through the Coopers DIY program where great education is available through Coopers Community forums and video.

Hopefully by the time "dangerous" vessels like glass bottles are used, a greater knowledge of process and safety has been accumulated.

Cheers

[Otto Von Blotto]

On 4/15/2019 at 12:36 PM, Worthog said:

 

Anyway, I am now 100% glass.

Cheers

I'm still flesh and bone

[Pezzza]

31 minutes ago, Otto Von Blotto said:

I'm still flesh and bone

Not so sure about that Kelsey... I reckon you are 99.5% Brew!  

[ChristinaS1]

3 hours ago, Bearded Burbler said:

Is that the brewery of the legendary San Fran Anchor Steam?

Has that some connexion to what is known as Dampf Bier (John from P911 had mentioned re potential for wheat beer yeast in an ale if I remember rightly?)

Anchor does indeed make a Steam Ale, for which they are famous, but they are also well known for Liberty Ale, which launched the American IPA revolution back in 1975. They were the first to dry hop with a fruity American hop, Cascade, which they used late in the boil as well. They also used and popularized the Chico yeast strain (aka WPL 001, 1056, US-05), which is often called an American yeast. Liberty Ale is considered a classic.

San Fransisco Steam Ale (aka California Common Ale) is a historical style which is fermented with a special lager strain adapted to ale-like temps. The style often uses Northern Brewer hops, which give it a distinctive woody and minty taste. I am not a fan.

Cheers,

Christina. 

Edited May 9, 2019 by ChristinaS1

[BlackSands]

On 4/15/2019 at 2:36 PM, Worthog said:

Yeah, the problem is that you can't know if they are end-of-life until they begin failing, either catastrophically as in your case, or worse, you find a percentage of your batch dead. This begins to get expensive and frustrating.

Mine had completed 10-15 cycles. Maybe people should manage their PETs to be replaced at, say, 10 cycles.

I've had numerous PET fails in the past and I would say ALL were as a result of excessive carbonation probably due to over-zealous priming or contamination.  The usual way my PETs failed was they developed a micro-leak somewhere on the bottom of the bottle.  The symptoms were boozy beer odours, fruit flies and a half empty bottle!   In a few cases I've had the entire bottom of bottles rupture.     

I've often wondered if the equivalent of 2 carb-drops pressurizes them close to their limits and repeated carbonation at this level results in eventual fatigue and subsequent failure.   I usually carbonate at a lower level compared to the equivalent of 2 carb-drops though, which may explain why some of my bottles have now seen far more than just 10-15 cycles.  Around 4 years ago I purchased 100 PET's for $1.  I had no idea of their usage history, but I bought new caps for them and the vast majority are still in use now.  

I have glass flip-top bottles too which are OK but are a lot bulkier and heavier than the PET's of course.  I can't be bothered with crown caps, bottling is a tedious enough process as it is though I actually do think that from an aesthetic point of view capped bottles are better.  Not sure about the arguments suggesting that glass tastes better... I'd need to see some blind trials done to be convinced of that!

[Pezzza]

19 hours ago, ChristinaS1 said:

Anchor does indeed make a Steam Ale, for which they are famous, but they are also well known for Liberty Ale, which launched the American IPA revolution back in 1975. They were the first to dry hop with a fruity American hop, Cascade, which they used late in the boil as well. They also used and popularized the Chico yeast strain (US-05),

that is pretty festive...  funny how different threads in life meet and go off again in different directions... had ages ago had this interaction with San Fran Anchor Steam ; )

I am keen tho on what P911 noted a while ago and I had a quick look - the Dampf Bier - using Weizen Yeast in an Ale type brew.... I did a tiny bit of research on net and it seems this was a thing on Germany Bavarois Czech border historically... caught a train from that border to Prague a long time ago... so think I really should have a crack at a Dampf Bier in honour of that trip and the Anchor Steam (Dampf) connexion?! 

Really just would be changing up the Yeast to a WB yeast in an Ale Ferment process... reckon that would be interesting.... 

[Pezzza]

8 hours ago, BlackSands said:

I've had numerous PET fails in the past and I would say ALL were as a result of excessive carbonation

I would suggest that if the PET is failing on over-carb it should not have been in the run-of-fill bottling anyway...   guess it is pretty hard to identify when to retire said vessel...  

[BlackSands]

3 hours ago, Bearded Burbler said:

I would suggest that if the PET is failing on over-carb it should not have been in the run-of-fill bottling anyway...   guess it is pretty hard to identify when to retire said vessel...  

..particularly when it happens to a brand new bottle!