Grey beer after kegging

[pirateagenda]

I recently brewed and kegged a hoppy hazy pacific ale style beer (75% ale 25% wheat us-05). I brew 110L batchs so i kegged 5 kegs worth.
I carbonate and cold crash in unitank and pressure transfer to co2 filled kegs. Now after kegging 3 kegs got put in the fridge, 2 of those have been finished and tasted great with the nice straw colour you would expect. The third is still going and tastes great. The 2 remaining kegs sat on the back deck for a couple of weeks. During this time there was some fairly warm days and the kegs would have been in direct sunlight.
Once these 2 have been chilled and tapped they have both turned a light grey very cloudy colour, lost a a fair bit of hop aroma and seem to have carbonated some more. I'm sure carbonation was complete as i had it in for about 7 days, then a few days elevated to finish it off. The beer doesnt taste infected, just lacking in hop character compared to the original and a completely different colour.

Any ideas whats cause this? Could heat from the kegs sitting in sunlight have caused oxidization in 2 weeks even though i have very low oxygen contact in my process? Would oxidization cause a pale beer to turn hazy grey?

 

[MHB]

Only seen hazy grey (looked like dish water) in oxidised highly hopped beers, NEIPA type of thing.
Its a lot harder to exclude all the O2 than people thing and it only takes a trace to really kill highly hopped beers.
They also tend to loose their edge pretty quickly, even under ideal conditions (cold, LoDo, don't shake them).
I think its best to treat them like you would a Hefeweizen, make small batches and drink them young and fresh - they just don't improve in package.

I'm trying to recall, I think it may have been Sam Calagione from Dogfish Head who coined the expression "fourteen days from grain to brain" (if anyone knows better please tell).

Best I can do toward LoDo in packaging is to fill the keg with de-aired water (boiled will do), blow it out with CO2, pressurise and counterpressure fill. Makes the beer last longer but nothing like the several months + that I would expect from most beers.
Mark

 

[pirateagenda]

Thanks Mark,

The beer was highly hopped with cryo hops. All things equal with the other kegs that were good - would the fluctuating temperatures of the kegs sitting on the deck have accelerated oxidisation that much?

 

[MHB]

Rapid and pronounced temperature change always accelerates aging, beer likes to be kept still, cold, O2 free and dark.
Anything else wont help, but sitting outdoors and going up and down 10-20oC a day will kill it dead!
Walk in cold room (I wish) is the perfect answer, anything else is a compromise. With highly hopped beers I would go from fermenter to fridge and keep it cold.
Mark

 

[Frothy Boi]

Grey beer? Reminds me of the short story "grey matter" by stephen king.