cider got grey/blue?

[mindaugas]

Hello, I was making cider ~year ago. Everything went fine (primary, secondary), i poured into bottles it, but surprisingly after 3 days when opening bottle color of cider was grey even a bit blue I poured off all mash and blamed some backteria or something.
Now year have pasted, i made couple of batches, tested them yesterday to decide about backsweetening. The half full glass that I left on the table at morning was of the same grey/blueish color. I wounder that I would get into same problem again.
Does anybody had this issue? What can it be?

p.s. I've used campden at beginning

 

[LiftedAWDAstro]

Was the half full glass left out over night open to the air? Maybe it is oxidation? Maybe your other batch didn't get sealed well enough.

Also what do you use for juice? What yeast?

 

[mindaugas]

Yes, glass vas left open overnight on the table.
I'm using regular white wine bioferm yeast .

 

[vtfireman85]

do you have any smurfs in your neighborhood?
seriously though, i would be interested to know about water quality and what you used to sanitize vessels with.

 

[mindaugas]

no smurfs, water is ok, everything sanitized same way as for beer making
any ideas? It's related to oxigen and happens actualy over night.

 

[gregbathurst]

Did you make your own juice from apples? If iron gets in the juice it will turn grey/black when exposed to air. Usually it is caused by the mill or press having mild steel components.

 

[Yooper]

It sounds like you have severe oxidation issues.

Pouring the cider into bottles would really be an issue, as fermented beverages need to be siphoned (not poured), headspace reduced, and protected from oxygen.

The other thing that can be happening is light damage. Ciders don't skunk the way beers do, but they can get "light struck". That means a color change and loss of flavor.

Usually, oxidation and light damage cause the cider to turn brown-ish (not blue) but it's hard to say without seeing it in person.

 

[bssrf4]

Pics of this futuristic blue space cider?

 

[mindaugas]

Yes, I pressed apple juice myself with big press. It's meda from metal/steel, yet hard to tell of how much exmpose it had to juice.
I repeated the experiment: poured a glass of cider and left it overnight on the table. It's turning grey again. Would post a picture after one more day also:

 

[gregbathurst]

You are getting iron dissolved in the juice. Apple juice is quite acidic and dissolves iron very easily. Try painting the steel parts with polyurethane paint.

 

[mindaugas]

ok, understood.
but how the juice (cider) staied ok in fermenter for two months? and only changes collor when exposed to air...

 

[gratus fermentatio]

While fermenting, the yeast expel carbon dioxide, which is heavier than air/oxygen. A layer of CO2 blankets the surface of the must & will push the oxygen out. The iron needs oxygen in order to cause the color change.
Regards, GF.

 

[Yooper]

I don't know about iron, but any cider exposed to air (with iron or not) will change color when oxidized. So will white wine and other fermenteds.

 

[mindaugas]

that's the whole picture.
Anyway - I haven't seen cider that naturally gets to this color when left on the table. And after another day it would become even more grey/blue

 

[gregbathurst]

The colour is due to oxidised iron. The good news is that your cidermaking process is good, you are keeping the air out which is very important. I have had the same thing happen, I fixed it by painting all steel parts that touch the juice. The colour change is generally called "blackening".

 

[mindaugas]

to those interested how in looks after 48 hours.

 

[rocketsan]

What kind of paint? Food grade I assume.


I was told to just rub the metal down with oil...

 

[gregbathurst]

I guess it depends on the part coming in contact with the juice. If there is a lot of movement and friction such as inside a shredder you need a few coats of a sturdy paint, if it is just the collecting tray of the press, it isn't so critical. The important thing is to get a barrier between any iron and the juice.