Beer is going flat

[user 35546]

Hey fellas,
Been drinking my brews from last winter, but I'm continually disappointed with the quality of the drink, in that they seem to have very little carbonation.

My Coopers Mexican Cerveza has turned dark and gone totally flat.

Here's my brew statistics for this particular batch:
Coopers Mexican Cerveza #13
Brew Date: 12 Jun 2014
Batch Size: 22 litres
Type: Extract Kit
Yeast: Coopers 11413INT
OG/FG: 1038 / 1006
ABV/ABW: 4.26% / 3.35%
Calories: 190 / 550ml
Bottling Date: 20 Jun 2014
Sugar: 1Kg Coopers Dextrose
Extract Can Expiry: 14-05-2015
OG Pre-Yeast: 1.038 @ 25c - 9.5BX
SG 18-06-2014: 1.006 @ 19c - 5.5BX
FG at Bottling: 1.006 @ 21c - 5.5BX

Why is this happening?

 

[panzerd18]

Bottling in PET?

 

[user 35546]

Yeah 60% of my brews were in Pet bottles.

 

[panzerd18]

Well thats your problem.

Believe it or not, the gas escapes through the plastic bottle wall.

Drink anything bottled in PET within 6 months.

 

[user 35546]

Ah crap, that's over 100 litres of beer [emoji31]

 

[panzerd18]

You said you do 60% in PET.

Can you test the same batch bottled in PET compared to same batch bottled in glass, just to be sure its the PET bottles?

 

[Blind Dog]

What size bottles? And is there any carbonation at all?

I'd be tempted to make up some sugar syrup and dose each bottle with a measured amount (syringe) and reseal and swirl to get the yeast up into the beer. Obviously use less than you used for the original bottling, but hard to say how much without seeing / tasting the beer. At a guess I'd go between 25% (a bit flat) and 50% (no fizz at all).

 

[user 35546]

I just use the off the shelf 740ml PET bottles from BigW.
I'll put some glass bottled brews in the fridge to try one tomorrow at lunch and I'll see how they are.
Thanks fellas, but if there's one thing I hate, it's pouring beer down the sink

 

[user 35546]

Oh yeah, I forgot to mention that most of the bottles have around 25% carbonation when opened, they're like really flat coke and taste like ****.

 

[panzerd18]

If you don't have the same issue with the glass bottles, you will then know its the PET.

 

[slcmorro]

I'm just asking here... are you aging Mexican Cerveza deliberately? Or did you make shitloads to start with?

 

[user 35546]

LOL, yeah I made about 66 litres of the stuff, and I'm only a weekend drinker. Also my expensive Coopers Sparkling Ale suffered the same fate, it's just as flat and tastes like crap.

 

[slcmorro]

You'll find there are certain beers that just don't age well. As a general rule of thumb (but not always accurate!) the darker the beer, the better it can hold up to aging. Some even improve with age. The two you've described however wouldn't be much better than lawn food after a year though, in my opinion.

 

[TheWiggman]

As above, if it's turned darker it's oxidised which is consistent with the beer being flat.
Smaller brews more often

 

[user 35546]

Ok thanks fellas, so I've learnt a couple of things tonite:
1) PET bottles are not good for long term storage
2) Light coloured beers don't age well

I'll remember all that when I start brewing again in Spring.

From all the Coopers extracts I brewed last year, I have to say their European Lager is a really nice drop. [emoji106]

 

[Straya]

Brewing in spring?

I'm a massive rookie mate but i just brewed a batch of white rabbit white ale a few weeks ago and the temperatures were fairly high for a couple of weeks there. According to my friend he said that due to the heat that the beer is exposed to when bottled the yeast becomes overly active and eats the something something proteins to give the beer a lack of head and make it taste like dog sh!t. However these beers weren't refrigerated they were in a mancave and were bottled 3 weeks after the boil and was an all grain brew. Not sure if this all equates to your process but just thought i'd throw it out there. I am a rookie though just relaying some info i was told Best of luck

 

[TheBigD]

why not throw another carb drop in there give it a week or two and drink.

I opened a sparkling ale (last one thank god)it was in PET and it was also flat I drank it anyway because it still tasted ok so if I had of had a few left I would of recarbed with another drop.

Since I keg I do smaller 21l batches and just bottle a few tasters in swing top flensburger bottles I bought from aldi (that are awesome) Ive only got 24 of them but will definitely grab another carton next time they have them.

 

[GNU]

May not be the most elegant method, but a soda stream maker can get bubbles in your immediately

May have done this once with a litre leftover from kegging [emoji57]

 

[manticle]

Homebrew specific pet or soft drink bottles re-used?

 

[user 35546]

Some good tips there, thanks fellas. I might try dropping a Coopers carbonation drop in a few and see what happens.

Manticle, these are purpose made PET brown brew bottles which I sterilised before using, including the plastic caps.

 

[manticle]

Cool. Brown ok, clear bad.

 

[pcmfisher]

I have drank 1 year old + beer in PET bottles.
It didn't taste particularly good. Oxidised yes, but in no way flat.

Coopers Cervesa with 1kg of Dextrose is never going to look good in a glass as far as head retention and bubbles go.
Often low body kit brews look flat and lifeless when they are actually fully carbonated. Maybe they are as good as they get.

Turning dark sounds like oxidation though.

 

[Rocker1986]

Would the yeast in the bottles even be viable enough after 12 months to actually ferment any added carb drops/sugar etc? :unsure:

 

[panzerd18]

I'm not sure if oxidized beer can be saved.

 

[Drewski]

Would the yeast in the bottles even be viable enough after 12 months to actually ferment any added carb drops/sugar etc? :unsure:

Not likely, i would not waste the time and carb drop to be honest.

 

[TheBigD]

Then add some yeast too surely you got a coopers yeast sitting in your fridge, I've got half a dozen.

Personally I like th the soda stream idea! Simple and fast.