2012 Old Vine Zinfandel

Two years ago, the old vine Zinfandel was a winner, and decided it was worth 10% extra a case to get the better, or perhaps supposedly better, grapes. The grapes were big and juicy, which is good and bad. Juicy grapes are usually less flavorful and have lower sugar -- think about it raisins make the sweetest juice since they have hardly any liquid. On the other hand, the skins were very flavorful, so I need to count on transferring flavor from the skins to the juicy for this to be successful.

Since the juicy was watery, I needed to add sugar (cane sugar) to make the wine strong enough. 

2012 Old Vine Zinfandel Wine Recipe

144 lb Valley Beauty Old Vine Zinfandel Grapes (crushed)

1100 g cane sugar (approx 2.4 pounds)

9 g potassium sulfite (to kill wild yeast)

16 g yeast energizer

1 Packet Red Star Pasteur Red Yeast and 1 Packet Red Star Montrachet

The juice had a refractive index of 23.4 degrees Brix. On this batch, I gave up on doing the density measurement. The density almost always agrees with the refractive index, and the refractive index is much easier. This would produce 12% alcohol. [My 2010 Old Vine Zin had much higher sugar so this is a little disappointing. ] 

Not everyone knows how to do this calculation, so I'll go over it. You need a sugar-to-alcohol table. 

I want 13.3% (28% sugar), and so I added 1100 g sugar.  I use a table in Pambianchi's Techniques in Home Winemaking, but an online table is here. At 23.4 Brix, I have 25.6% sugar and I want 28% sugar (for 14.5% alcohol). I need to add sugar for (28-25.6)/100*144lb = 3.4 lb = 1570 g.

The juice fermented quickly, and I pressed it. I got 33 liters or 8.7 gallons that is 8.25 L/case or 2.2 gal/case.