Iridescent Spots on Year in Bottle Blackberry Wine

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MI hobbyists

Oct 28, 2021
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Hi everyone I'm new here and couldn't find an answer through other peoples questions so I thought I'd ask. I have a bottle of Blackberry wine I made in February of 2020. I made it from full Blackberry's pureed and strained through cheese cloth, and some lemon juice. Primary and secondary went well and I put it on oak chips for a month after and racked into Bentonite to clear. After it cleared racked into bottle.

Its been over a year in its bottle and I've pulled it out to see if its doing alright and noticed a patchy iridescent on top. I've not incountered this with any of my other brews but most of my brews are mead (aside from an amazing dandelion wine).

I've checked the brew every few months but the last time I checked was in May. I did bottle it with a Argon gas because there was more head room then im comfortable with. This was my 20th brew and 4th with real fruit. It smells fine but didn't want to risk tasting it if its bad. Is this safe or should I pitch it? Was really hoping to take it to a Halloween party this weekend.

(Sorry the photo is so bad best I could do)

Starting gravity was 1.080
Final gravity is 1.000
I didn't back sweeten it, thought I'd try a dry brew this time.


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It smells fine but didn't want to risk tasting it if its bad.
Trust your nose more than your taste buds. If the wine smells fine, it's 99% likely it's fine.

I can't tell from the photo what I'm seeing. Personally, I do not trust invisible gases as there is no way to tell if the wine is protected or not, e.g., if all the air is displaced. Better to top the bottle with a compatible wine, as then you are 100% sure.
You can give it a taste. You will know immediately if it "off". Do the spots disappear when you pour the wine in a glass? if so, it may just be a bit of c02 or pectin haze. If you are really concerned about the appearance, open two bottles, pour off the spots, taste the wine and re-bottle and re-cork one for your party. I've done that when a wine drops more sediment after bottling.
I've racked the brew into another bottle careful to avoid the spots. I think you might be right VinesnBines about it being pectin. Here a photo of it on the wall of the bottle.


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your wine is safe, wine is a preservative system, so you won’t have food poisoning. ,, it may develop off flavors but that is all.

. . It smells fine but didn't want to risk tasting it if its bad. Is this safe or should I pitch it?
Starting gravity was 1.080
Final gravity is 1.000
welcome to wine making talk
I've made a lot of blackberry wines, never seen this, but I have a different method (i.e. never puree use the bag and squeeze whole berries)... want to throw this out to the experts on the line and see what they think... I note dyou said you pureed whole berries, this would probably crush and chop the blackberry seeds (of which there are lots on blackberries, though small). I know that grapes have lots of oils in their seeds (even a whole business - grape seed oil), was wondering if the seeds of blackberries, even though they are small, would have some oils or something that could cause this if they were pureed.? Any thoughts on this?
@Fencepost , yes there will be some oil in blackberry seeds, not enough that it is commercially interesting. ,,, That said grape seeds are not as high as oil seeds which tend to be 30 to 35% fat.

I do not have enough information to guess if the sheen is mineral or bacterial. The wine is probably 10% alcohol which is low, but OK and the blackberries I have looked at ranged from 3.3 to 3.9, so with lemon again pH should be OK. On a risk basis microbial happens often enough that is what I would test for. Mineral would suggest some complex with water based chemicals/ wine additives. Oil on a numbers game if there is 2.5% seed in the carboy and a seed has five percent lipid, it’s not a lot, ,,,,, a test to rule out oil, pull 100 ml/ two oz of sheen off wine and add 25 ml acetone, a lipid will dissolve in the solvent.
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i had that kinda problem, i was told to just skim it off, everybody knows i'm on the hardheaded side,,, since i had another 100+ gallons so i set them two 6's to the side, that film now has pulled it's self to the outta edges of carboy, am told it smells fine, i did this since i had plenty drinking wines, it is over 2 years old now, i plan to take most leaving the film, i should get 1 bottle short of 5 cases, i just had to see what would happen, now i'm getting ready to bottle away from my other wines,, i will label them different so they cant get mixed up,

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