Clibit
This is a very revealing exbeeriment! Well worth a read for anyone who ever uses liquid malt extract or liquid malt kits.

http://brulosophy.com/2017/11/27/the-impact-of-age-on-liquid-malt-extract-exbeeriment-results/

The same beer was made twice, a German bock lager, all the malt in each was from a can of Pilsner LME, but one batch had LME that was 8 months older than the other. No grains or other malts or sugars. 100% LME.

There was a huge colour difference, and taste difference. The old LME was much darker (see the photos - could explain that lager kit I once did that was caramel coloured! And very malty). Quote...

"These beers were so starkly different to my understandably biased palate that I was able to select the unique sample in every triangle test I attempted. In both aroma and flavor, the beer made with fresh LME had a grain-like sweetness and oyster cracker finish compared to the caramel and melanoidin character I perceived in the old LME beer. I even thought the mouthfeel was different with the fresh LME beer being cleaner, drier, and lingering less on my palate. Selecting a preference was difficult because it sort of depends on the context. As a lager, the fresh LME was more inline with my expectations, but the old LME beer was actually nice too, it just had a stronger malt characteristic more reminiscent of a Scottish Ale."


Interestingly, the numbers that preferred each beer were pretty even. 11 fresh, 9 old. Just two very different beers.

"Based on both post-survey conversations with participants and my personal experience, the beer made with fresh LME was lighter, crisper, and tasted more like the German Pilsner it was meant to be while the old LME beer was perceptibly more like a malty ale."

When we buy LME, or LME based kits, we are in the lap of the gods really - how old will the kit be. It is likely to make a huge difference. We already knew this, but this exbeeriment really spells it out, and the difference is huge.
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Clibit
I'm pretty disappointed in the lack of interest in this thread! [rolleyes]  [rofl]

I think it's a really revealing xBmt. Check out the two beers, for starters...


12_OldVsNewLMEage_freshGLASSESold.jpg 

Identical beers except the extract in one was 8 months older than the other. Beers that looked and tasted completely different.
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AdrianDBW
I was interested and read the article... But I've decided I don't like LME so had nothing to add. 😂
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Clibit
AdrianDBW wrote:
I was interested and read the article... But I've decided I don't like LME so had nothing to add. 😂


Fair dinkum!  [rofl]
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HisDudeness
I had read this one already and also thought it very interesting, as I don't brew kits or use LME its doesn't make much difference to me anymore but it certainly helps explains some of the results I had with different kits. What I'd like to know is what process is occurring here, is it just oxidation or is there something else at play?
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Clibit
HisDudeness wrote:
I had read this one already and also thought it very interesting, as I don't brew kits or use LME its doesn't make much difference to me anymore but it certainly helps explains some of the results I had with different kits. What I'd like to know is what process is occurring here, is it just oxidation or is there something else at play?


Good question. The cans will be vacuum sealed, so I wouldn't imagine it's oxidation - or does oxygen make it into the can?
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HisDudeness
That’s what confuses me, surely the canning process should be eliminating oxygen but things like the colour darkening would make me suspect oxidation as being at least partly involved
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GHW
Maybe there were batch related diffferences as well as age.
I’m sure lots of chemical reactions take place as the product ages
It is very pronounced in the photo though.

Not that many of us do extract beers phil, especially lme. I’d always use dme as it’s easier to handle
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Clibit
GHW wrote:
Maybe there were batch related diffferences as well as age. I’m sure lots of chemical reactions take place as the product ages It is very pronounced in the photo though. Not that many of us do extract beers phil, especially lme. I’d always use dme as it’s easier to handle


I usually use DME when I do a partial mash, occasionally LME. And we have kit can brewers, which are hopped LME.

DME doesn't seem to suffer the same way. So it it the presence of residual water in the can that causes the deterioration? Water = H2O. 
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GHW
View it like orange juice:
Freshly squeezed = best (all grain)
Concentrate (dme/lme) = less good
Fresher concentrated = better (dependent on taste, but if doubt fresher is probably better)
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Clibit
GHW wrote:
View it like orange juice: Freshly squeezed = best (all grain) Concentrate (dme/lme) = less good Fresher concentrated = better (dependent on taste, but if doubt fresher is probably better)


Started off really well that analogy.  [thumb]  [rofl]
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