Here is a log of sorts of how I am making Blueberry Wine. The recipe is from The Home Winemakers Companion by Gene Spaziani and Ed Halloran. I also see this recipe, or very close to it in other places. There is one main difference between the source recipe and this batch, Frozen Supermarket Blueberries. I'll update this main post as the wine matures and add a final measurements graph. Recipe 10-15 lbs of frozen blueberries 10 lbs granulated sugar 5 tsp acid 1-1/4 tsp yeast nutrient 10 drops of pectic enzyme 1-1/4 tsp of grape tannin 1 oz American Oak chips I pack Red Star Cotes des Blancs yeast Enough water to make 5 gallons Day 1 I boiled 2-1/2 gallons of tap water and added 9 lbs sugar to it, dissolving it completely. While the water was boiling I put the 4 packages of semi thawed blueberries and one 1 lb package of mixed berries (for 13 lbs total), as well as the remaining pound of sugar into the fruit bag and into the primary. I poured in the boiling water and stirred until fully thawed. I added remaining cool water to 5-1/4 gallons total to bring the temp down to approx 75f. When cooled I added all the ingredients to add body and flavor to the must, except the yeast. I added 5 campden tablets, stirred it for 5 minutes and let it sit over night Readings: Temp - 72f SG - 1.105 Acid - 43% Day 2 Took acid readings using Pheno and still appears low, approx 50%. A proper level would be approx 65% which would mean adding 5 additional tsp of acid mix. This seems like too much to add at a single time. So I add 2-1/2 tsp of acid mix to bring it up approx 7%. I don't want to be too aggressive, there may be undissolved acids, or it may come from the fruit as the pectin breaks it down. I also add the yeast. Day 3 I use a gallon sanitized jug and from the valve on the primary I fill it twice and pour it over the fruit bag, back into the primary. The bag is floating nicely and smells of CO2 and berries. SG - 1.098 Acid 62% Day 4 and 5 Stirred and punched down Day 6 Still active. Stirred and punched down Temp - 72f SG - 1.074 Acid - 63% Day 7 Stirred and punched down Day 8 Temp - 71f SG - 1.065 Acid - 65% Day 9 Considerable slowing of bubbles Temp - 70f SG - 1.063 I removed the bag of fruit and placed in a sanitized bowl, squeezing the juice from it and adding it to the carboy. I rack the primary through the valve and tube into a 6 gallon carboy, adding just over 1/2 gallon of additional water to reduce SG and acid. It's topped with an airlock. I also placed the bottom lees into a separate covered glass measuring vessel for later examination. SG - 1.056 Acid - 60% It's barely bubbling, I hope it's not stuck. Day 10 I left the lee's out in a saran wrap covered glass bowl, it's fizzing fiercely. After a quick look I realize it's a thick mush and toss it out. The carboy is bubbling nicely, and appears very sensitive to light. It's in a dark closet and I use a tactical flashlight to illuminate it. There is an inch of thin, pink foam across the top until I shine the flashlight, which is very bright. The foam breaks and leaves bubbling smooth liquid. When I remove the light the foam again covers the must. This tells me that a dark closet is the best for this yeast. The whole container is active and the airlock bubbles once every 3 seconds.