Saturday….busy productive day….

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.

  1. A= The current Brix (sugar content) of the must is 20, leading to a potential alcohol (PA) of 11%
  2. 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.
  3. 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!



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