Mind posting this recipe? Was it a blueberry ale or wine? Just thinking about what late addition could mess with OG unless its something like honey or simple like to much top up water.
I believe this is a wine. I had read some comments by people having trouble with higher abv recipes and blueberries. The basic idea was to see if there was something endemic to blueberries that was causing off flavors at higher abv targets. I hadn't planned on adding the syrup, but I have several other kinds of syrups and didn't particularly need another one cluttering up my kitchen.
I know the name is lame, but I haven't thought of anything that's right for the recipe yet.
Blueberry Wine
Batch Size: About 1 gallon.
OG: 1.160
FG: 1.020
ABV 18.7%
In primary:
1 qt rw knudsen just blueberry.
1 bottle mama's choice whole blueberry syrup.
I can't find the bottle, but it was about 12 oz.
About 1.3 lb of sugar.
I didn't actually weigh my sugar first, so this is estimated.
1 tsp dry distillers yeast.
1 tsp yeast nutrient.
1/2 tsp yeast energizer.
In secondary:
1/2 tsp powdered bentonite.
2 old pennies
Here are my actual notes:
my notes said:
10-27-2012 10:00 pm: Mixed up blueberry wine. 1 qt rw knudsen just blueberry. 1 bottle mama's choice whole blueberry syrup. About 1.3lb sugar. Gravity 1.16. Higher then I intended. Syrup has corn syrup in it. Probably won't ferment dry.
11-11-2012 12:00 am: FG 1.020 18.7%. Funny smell to it, reminds me of the weirdness from the cherry limeade. Kinda nasty muskiness. Added 1/2 tsp bentonite. Split into 2 bottles, needed the 1 gallon jug.
11-12-2012 11:30 pm: Funny smell still present. Probably H2S. Added an old penny to both bottles. Shook them like hell. Smell is gone. Awesomeness. Will let these settle out again and bottle. Stuck in fridge to cold crash.
11-22-2012 7:00 pm: Bottled 1/2 blueberry wine 4 12oz bottles.
I always use yeast energizer and yeast nutrient when I make wine or cider, I only make notes about it if I'm using amounts that are different from my standard setup. The same goes for the yeast.
I drank the other 2 quarts of this after it had settled in my mini fridge. I was
for about 3 days off of it.
Doing this again I would probably use 1 1/2 tsp of yeast nutrient, that would probably take care of the H2S issue.
I was aiming for 1.1 and had planned to use a champagne yeast. When I saw how high the OG actually was I decided I'd better use a yeast with a higher alcohol tolerance or the end product was going to be disgustingly sweet.
Distillers yeast is also the least fussy yeast I've ever used, and I didn't feel like making a starter.
I do not believe that there is anything about blueberries/blueberry juice that is causing off flavors. It is more likely that they simply don't contain some nutrient the yeast needs, so the yeast is becoming cannibalistic.