Plum Wine, Oily surface in Demijohn

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Spapro

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Hi,

got a blackberry wine on and a plum wine - first go at wines (brew all grain beer a lot).

28/8/17 Started my Plum wine off - used 6 campden tablets and pectin
29/8/17 Added Youngs Grey GV5 yeast.
03/9/17 transferred to clean bucket (through sieve)
09/9/17 transferred to clean bucket (14litres) - SG was at 0.996
11/9/17 transferred to demijohns - got 3 full and a 1/4 full demijohn

Been sitting at 19°C since - so 2 weeks nearly and today noticed a oily type layer in all full demijohns (not in the 1/4 full demijohn).

Think its just about done fermenting to be honest.

Anything to worry about? By product of yeast activity? should I do anything now ?

Pictures:

Plum_Wine_oily.JPG


Plum_Wine_oily2.JPG
 
That's a strange one. I have 20 litres of plum nearly finished fermenting at the moment.

Just checked it and there's nothing like that on top, although it has lost all the nice plum flavour it had at the start.

Did you wash off the plums before starting them? It appears to be a contaminant and the most likely cause is something the plums were sprayed with while growing, I would have thought. Is there a chance one of your vessels had a contaminant?

Has it affected the flavour? If not I would be inclined to re-rack a DJ leaving any sediment and oil behind to see if it happens again.
 
Yeah sorry mate it looks like the early stages of acetobacter. Basically, like yeast turns sugar into alcohol, this stuff turns alcohol into malic acid (vinegar) It's aerobic so it needs oxygen. It's not harmful to drink, however, it will get progressively worse. You only need the tiniest flake of bacteria from a common flys leg to dick your whole batch. Googleimage search acetobacter infection
 
Yeah sorry mate it looks like the early stages of acetobacter. Basically, like yeast turns sugar into alcohol, this stuff turns alcohol into malic acid (vinegar) It's aerobic so it needs oxygen. It's not harmful to drink, however, it will get progressively worse. You only need the tiniest flake of bacteria from a common flys leg to dick your whole batch. Googleimage search acetobacter infection

Thanks for the tip.

I made the mistake of looking at images of this as well. :doh:

I just lost my appetite.
 
Yeah no drama mate. It is pretty nasty stuff. You could literally touch a work surface that a fly has landed on then touch a sterile spoon you use to stir it with and that's it, done. There's no way of knowing how it happened, it's just a ****ter. I've heard of some people bottling it up right away and consuming it fast and they've been fine, either way you have to do it soon and our main enemy is oxygen. Post some more photos of how it gets on.
 
That's a strange one. I have 20 litres of plum nearly finished fermenting at the moment.

Just checked it and there's nothing like that on top, although it has lost all the nice plum flavour it had at the start.

Did you wash off the plums before starting them? It appears to be a contaminant and the most likely cause is something the plums were sprayed with while growing, I would have thought. Is there a chance one of your vessels had a contaminant?

Has it affected the flavour? If not I would be inclined to re-rack a DJ leaving any sediment and oil behind to see if it happens again.

Thanks for your thoughts.

Plums were grown on a small tree in our back garden, so not treated/sprayed with anything. The plums were rinsed off and then mashed with campden tablets and some boiling water then left before adding the yeast.

Demijohns were cleaned out with oxiclean and rinsed really well, then starsan'd before filling.

Bit stumped, although my first attempts at wine so trying to learn so all thoughts/advice appreciated.
 
Yeah sorry mate it looks like the early stages of acetobacter. Basically, like yeast turns sugar into alcohol, this stuff turns alcohol into malic acid (vinegar) It's aerobic so it needs oxygen. It's not harmful to drink, however, it will get progressively worse. You only need the tiniest flake of bacteria from a common flys leg to dick your whole batch. Googleimage search acetobacter infection

Will have a think then probably rack off to clean demijohns and bottle if it doesn't go manky in the clean demijohn.

thanks for the advice.
 
Yeah sorry mate it looks like the early stages of acetobacter. Basically, like yeast turns sugar into alcohol, this stuff turns alcohol into malic acid (vinegar) It's aerobic so it needs oxygen. It's not harmful to drink, however, it will get progressively worse. You only need the tiniest flake of bacteria from a common flys leg to dick your whole batch. Googleimage search acetobacter infection

Got to correct your acids here acetic acid is the main acid in vinegar not malic acid, the latter is wanted in cider and a number of wines to turn into lactic acid.

The oily substance looks more like a fungal infection rather than bacterial, although it could be. Not sure that the sanitisers are good to use with wine making. It's possible they may have reacted with something in the wine or plums to produce the oily surface, alternatively the camdens could have reacted with the sanitisers. Saying all that it may just be small remants of the plum skins.
 
Hi,

Been sitting at 19°C since - so 2 weeks nearly and today noticed a oily type layer in all full demijohns (not in the 1/4 full demijohn).

Think its just about done fermenting to be honest.

Any further updates on this?
 
Not convinced about acetobacter infection, given the precautions taken. Some varieties of plums do produce an oily residue in wine. You can mop it up with a paper towel or carefully rack the wine.
 
Not convinced about acetobacter infection, given the precautions taken. Some varieties of plums do produce an oily residue in wine. You can mop it up with a paper towel or carefully rack the wine.

Thanks Tony, your post gives me some hope !

Will take a gravity reading and bottle if ready in the next week or two (racking carefully from under the oily surface).
 
Just wanted to update for others benefit who come across this thread.

The oily film subsided with time, bottled 17 bottles today after transferring to clean Demijohns and stabilising last week.

Ended at 0.996 gravity which gives it 11.5% ABV which seems ok. Tastes a bit sharp but promising and hoping it mellows with some time in the bottle
 
I always get concerned if my plums get oily! :lol:

Sorry I couldn't resist.

On the contrary... this is a sign that things are going very well. Anyways, out of 9 gallons of blackberry wine I made last year, 4 have just gone down the plughole - distinctly acetic and with a growing haze. Gutted.
 
out of 9 gallons of blackberry wine I made last year, 4 have just gone down the plughole - distinctly acetic and with a growing haze. Gutted.

That's certainly a big loss. As I dislike the taste of sulphite I store my wines for up to a year without any added preservatives. However your experience has made me re-think this risky approach.
 
That's certainly a big loss. As I dislike the taste of sulphite I store my wines for up to a year without any added preservatives. However your experience has made me re-think this risky approach.

The 4 gallons of bad wine were in one of those water-dispensing carboys. Either it wasn't airtight / infection had gotten in during filling or maybe the plastic itself had allowed oxygen to enter over the 5 months it was in there. Everything in glass is fine.
 
". . . allowed oxygen to enter . . ."

Yes, somehow there was enough oxygen for the acetobacter to thrive. FWIW I minimize exposure of finished wine to air by deep syphoning, first into glass DJs for sediment to drop out and then into 2L pets (squeezed after filling to exclude all air) for storage. Despite being careful I still lost a few litres of blackberry wine recently when the sediment on which it was sitting went rotten.
 
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