Taste Difference Between Bottles - Ag

[brando]

Guys,

Now drinking my first AG beer, the famous Dr Smurto Golden Ale recipe, and it is very good. It has been bottled for 2.5 weeks now.

The unusual thing is that I have bottled in both glass and PET and the taste difference between the two is very noticable. Almost like two different beers.

Most of the beer was put into 740ml PET bottles, and the flavour of this beer is comparably more malty and less bitter than in the glass bottles.

I bottled only two glass stubbies (midway during the bottling process), and the taste is not malty, quite bitter, and perhaps a bit hoppier. I assume this version is closer to what the recipe should be like.

Carbonation levels between the two are virtually the same.

Both beers taste great, but different.

Any ideas?

p.s. I can easily tell the difference between coke from PET and coke from a can, so I assume the same kind of flavour influence is happening here.

 

[manticle]

Are you pouring into glass or drinking straight from the bottle?

 

[brando]

Always pour into glass.

I wonder whether it is just a timing issue regarding conditioning, due to 740ml vs 375ml bottles?

 

[Spartan 117]

I had the same thing happen when I breewed a batch on old english ale, the glass bottled beers where noticably different to the PET again they where both nice but there was a distinct difference.

Aaron

I'll see with my next brew if my uni will let me borrow there HNMR to test the beer.

 

[buttersd70]

@ brando:
I've yet to find a reference as to the why of it, but it is commonly held that larger volumes age faster than smaller ones. example is chimay website, referring to the magnums vs normal bottles, and also the common trueism that a keg is ready earlier than the same volume in bottles....
I think it's got to do with volume vs headspace, but as I said, I can't find a reference as to why.

 

[Fourstar]

@ brando:
I've yet to find a reference as to the why of it, but it is commonly held that larger volumes age faster than smaller ones. example is chimay website, referring to the magnums vs normal bottles, and also the common trueism that a keg is ready earlier than the same volume in bottles....
I think it's got to do with volume vs headspace, but as I said, I can't find a reference as to why.

Ive noticed this before as well, if its got todo with headspace id point it to oxidation. it may also be the fact that (i find) with all my kegs, the longer they are held at fridge temps the faster they condition, it may be due to the rate @ whcih yeast floccs out. The same thing goes for filtering apparantly, it conditions a green beer faster as it strips away yest and trub whcih will usually give you yeast bite/hop sharpness etc.

 

[Effect]

I bottled some beer in PET and in glass Grosch bottles...

All I found different were the carbonisation...the PET was quite lower than the Glass and the batch was bulk primed. I think that it has something to do with the 'give' the plastic bottles have, that the glass doesn't.

Taste wise they were practically identical...

 

[warra48]

@ brando:
I've yet to find a reference as to the why of it, but it is commonly held that larger volumes age faster than smaller ones. example is chimay website, referring to the magnums vs normal bottles, and also the common trueism that a keg is ready earlier than the same volume in bottles....
I think it's got to do with volume vs headspace, but as I said, I can't find a reference as to why.

Interesting.

That seems to run counter to the wine situation.
Usually bottles mature earlier than bottles, which mature earlier than magnums.

I don't know why, but my brews seem to hit their straps after about 2 to 3 months in the bottle, whether that's stubbies or longnecks. I've not noticed a difference.

 

[brando]

Next time I will be experimenting more at bottling time to try to work out an accurate theory as to why this is happening.

I'll try a combination of 375ml glass; 750ml glass; 375ml PET; 740ml PET; 1.25L PET and 2L PET.

I'll taste them at different intervals. I expect that in time they will all come back to tasting them same, and hence confirm my suspicion that it may just be a timing of maturation issue.

 

[Muggus]

It could also have something to do with plastic absorbing more oxygen than glass.
Not sure if that would dramatically change a beer in the space of 2.5 weeks though, but definately would in the long term.

 

[Hasa]

@ brando:
I've yet to find a reference as to the why of it, but it is commonly held that larger volumes age faster than smaller ones. example is chimay website, referring to the magnums vs normal bottles, and also the common trueism that a keg is ready earlier than the same volume in bottles....
I think it's got to do with volume vs headspace, but as I said, I can't find a reference as to why.

Next time I will be experimenting more at bottling time to try to work out an accurate theory as to why this is happening.

I'll try a combination of 375ml glass; 750ml glass; 375ml PET; 740ml PET; 1.25L PET and 2L PET.

I'll taste them at different intervals. I expect that in time they will all come back to tasting them same, and hence confirm my suspicion that it may just be a timing of maturation issue.

To get more scientifically relevant results to either confirm or deny the either correlation or causation of volume vs headspace determining the rate of maturation, it would be necessary to actually calculate the ratio between volume and headspace for each of the sizes and have a few data sets where the ratio corresponds to that of a particular size, eg. calculate the ratio for 750ml glass, then fill all the other bottles in that set to that ratio.

One would also hypothesize that the volume vs headspace ratio would be just one of the factors that determine the rate of maturation, ie. temperatures are more stable with a larger volume or the partial pressure of carbon dioxide might be more consistant in PET.

 

[drtomc]

The difference in perceived bitterness could also be related to the plastic vs glass surface. It is possible that the hop compounds adsorb onto the plastic to a different degree compared to glass, and are thereby removed from the beer to a certain extent. One for the analytic chemists.

T.