notes

Procedures

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Formulas and Measurements

Rule of thumb from Divine Consultants: 1 vine = 6 bottles

300 bottles when we are at full production for our 50 vines

Rule of thumb: 1 ton of grapes @ 125 gallons Corollary: 1 ton of grapes @ 125/.264 liters @ 473.5 liters = 473.5 x .8 bottles = 378 bottles Corollary: at full production we will have 300/378 tons @ .8 tons. Estimated % alcohol = (° Brix – 3) x Specific gravity x .59 where Specific gravity is specific to ° Brix (see Table 5 on p. 11 of MTWaH) Citric acid solution = 250 g./4 gallons (from Brian) = 125 g./2 gallon bucket

205g. net weight in 150 ml. beaker (which weighs 80 g.)
slightly less than 140 ml. for 2 gallon bucket
70 ml./gallon

Bleach solution = 1 cup /4 gal. (from Brian)

Weight of grape crate = 79.4 – 77.8 kg.

= 1.6 kg.

The spreadsheet below subtracts this for each crate to get net weight of grapes from the gross weight.

Weight of 30 gal. primary fermentation container = 94.4 – 90.6 = 3.8 kg. 1 ppm = .001g./liter

K₂SO₅ (aka SO₂) solution for 10 ppm = .08 g. / gal. (from Brian)

1 package Pasteur Red yeast/5 gallons = 1g./gal.

1.8 g. Superfood /gallon

1 g.vinaflora oenos/gallon

.2g. Leucofood/gallon

Cleaning

Clean well = rinse well with water, scrub with bleach solution, rinse well, scrub with citric acid solution, and rinse well (WBWCW)

Clean = rinse well with water, scrub with citric acid solution, and rinse well (WCW)

We clean after use well enough to prevent things growing on surfaces and clean obsessively before use. We can be somewhat less obsessive about cleaning,

To obviate worrying about bleach left in the bristles, we dedicated brushes to each of the bleach and citric solutions. We also dedicated a scrubby, marked with a cutoff corner, to the citric solution.

Measuring Sugar Before Picking

Measuring the sugar content of grapes prior to picking is done with a refractometer. For each measurement, collect eight grapes per full row in a baggie; collect proportional amounts from shorter rows. The grapes must be representative of the vineyard: different size grapes and from different places within each bunch.

Crush the grapes in the baggie to get as much grape juice as possible. Mix up the juice well to get the best measurement.

Take several readings because they differ, sometimes by as much as .8° . (Why is this? This is somewhat unsettling.)

Making K₂S₂O₅ Solution

50% of the K₂S₂O_5.produces SO₂.

Based on the desired concentration, calculate how much K₂S₂O_5. In 1996 we calculated based on weight (08 g/gal for 10 ppm), which we then added to a small amount of water, typically 100 ml..

This is a tiny amount of potassium metabisulfite for 7.5 gallons

In 1997 we prepared 10% stock solution of K₂S₂O₅: .

10% stock solution = 100g per liter

200ml = 1/5 liter of stock solution

Þ add 20g to 200ml of distilled water.

We then followed Table 4 on p. 9 of MTWaH to see how many milliliters of this stock solution to add to get to 40 ppm for the number of gallons of must we were working with.

To make the solution, put on the gas mask and blue gloves for handling chemicals.

We have been exceptionally careful in handling the K₂S₂O_5.We are told that we do not need to be quite as paranoid as we are in working with the K₂S₂O₅, but it sure seems like a risk that we do not want ot run at all.

Measure out K₂S₂O₅ with a plastic spoon into the weight boat on the scale. Be careful in disposing of both the spoon and the weight boat.

Add the K₂S₂O₅ to 100 ml. water in a beaker. Using the magnetic stirrer, mix well.

According to MTWfG, a stock solution loses its strength with repeated use.

Adding SO₂

We used less SO₂ the first year than we should have. Our plan was …

We added only 20 ppm initially, with the plan to add 50-75 ppm more if problems developed.

The amount of SO₂ to add is

40 ppm at pick

overall SO₂ strategy

Adding Yeast and ML Bacteria

Measuring and Adjusting Acidity

FVtW recommends a total acidity (TA) of .60 to .80. Adding 3.6 grams of tartaric acid per gallon will raise the TA by .10. We have not found a formula for how much potassium carbonate to add to lower the TA. FVtW (p. 146) recommends using the malolactic fermentation or cold stabilization as "safe" ways to lower the acidity.

FVtW recommends a range of 3.3-3.5 for pH. Our focus is TA, not pH. If the pH is out of whack, look more closely at the TA.

Basic idea in measuring TA:

Add a base (NaOH) to adjust a beaker of distilled water to an established pH level.

Add a known quantity of wine to the beaker.

Add base to the beaker until the solution is again at the established pH level.

The amount of base required determines the titratable acidity.

Filling with Nitrogen

Attach the hose snugly to both the nitrogen tank and the Pepsi container;

Turn the nitrogen pressure nozzle on until pressure reaches XXX on tank dial;

repeat do repeat do Close the pressure release on top of the container;

Snuggle the container top on to ensure a tight seal;

Turn the regulator knob very slowly until pressure reaches YYY on the regulator dial; Close the regulator knob;

end

until no hiss from the seal while pressurizing;

Open the pressure release on top of the container;

end

until there is a strong phoosh while opening the pressure release;

Close the pressure release on top of the container;