Woke us this morning with a busy morning schedule. My sweetie and I plan to have dinner this evening, so no working late into the evening! First was the check on the wine must and the yeast starter. I fed the happy yeast more sugar, warm water, and some more nutrient. It is a strong starter so once pitched, it should soon begin to ferment the plum must. First, however, I needed to check the specific gravity, PH, and acid.
Brix/Specific Gravity (S.G.)/Potential Alcohol (PA)
To test specific gravity, I use a tool called a hydrometer. This tool measured the specific gravity of sugar in wine must, helping to determine the potential alcohol when finished. Using Pearson’s Square, I will be able to determine if I needed to increase/decrease the sugar in my must to achieve my desired finished alcohol percent.
- A= The current Brix (sugar content) of the must is 20, leading to a potential alcohol (PA) of 11%
- B= The current Brix (sugar content) of my simple sugar assembled this morning. For every 3 cups of sugar, I dissolved it in 1.5 cups of boiled water. This mixtures Brix is 70.
- C= My desired finished is a Brix of 28 with a PA of 16%
To find the part of my wine must that is ‘juice’ (D) and ‘strong syrup’ (E)
- D= B-C 70-28=42 parts of juice
- E= C-A. 28-20=8 parts of sugar syrup
- D+E=Total Parts….42+8=50
To use this information, we need to equate the parts to fluid ounces. Using proportions and ratios:
- D= 42/50 = .84 or 84% juice
- E= 8/50 = .16 or 16% syrup
- .84+.16 = 1.00 or 100%
For every 128 ounces, 84% should be juice and 16% should be syrup.
- 128*.84 = 108 oz.
- 128*.16 = 20 oz.
For 6 gallons: 20 *6 = 120 ounces should be syrup or about 15 cups of syrup. After adjusting, I started with:
- Brix of 26.5
- SG of 1.112
- PA of 15% (wine typically is around 12%….I like to go a little high to account for topping up as ferment/rack.
For my acid test, I use a wine makers acid text kit. For country wines (those made from fruits other than grapes) the goal is to have a Tartaric range o .55 – .65. When testing, the reagent is drawn into a ml syringe. As it is added to the test tube of must, I keep track of how much was injected into the sample until it has a color change. (For this light wine – it will turn magenta pink.) I had to add 5 ml before the color changed. For each ml you multiply by .25 giving the acid content in percent of tartaric. So mine equates to 1.25 My goal is .55 – .65. My must needs more acid per the test. I need to add the equivalent of .60 to change my results. Each tsp. Of acid blend, adjust .15 tartaric, so I need to add 4 tsp of acid blend. I added to the must but will retest tomorrow when the must has had the chance to mix.
Using a basic PH strip, I tested my must and it is reading at 3.2.
Pitching the Yeast
After adjusting the must of sugar, adding acid blend, and testing PH, I pitched the yeast. Hopefully by tomorrow morning, I will wake to fermentation in the bucket!