Winemaking Calculations - Food · PDF fileWinemaking Calculations Amanda Stewart ... Why? Microbial Stability Inhibition of browning enzymes ... Proficiency in winemaking calculations

Winemaking CalculationsAmanda StewartPurdue Wine Grape Team29 April 2011Spring WorkshopBuck Creek Winery

SO2 is on Your SideWhy?Microbial StabilityInhibition of browning enzymesBinding of acetaldehydeAntioxidant

Commercial average 74 mg/L

C. Butzke 2006, Wine Quality Control Basics

Free SO2 and pH

pH Free SO2 REQUIRED

Free SO2 and pH

Example Calculation

Assume 1000 gal of winepH = 3.44No SO2 has been added yetPlan to bottle with residual sugar

How Much SO2?For pH = 3.44, we need:

Plus an extra 30 mg/L to cover losses

Addition:

35 mg/L Free SO2

35 mg/L + 30 mg/L = 65 mg/L Free SO2

How many grams to put in the tank?

UNITS!1 gallon = 3.785 Liters 1 gal/3.785 L = 1

1 g = 1000 mg 1 g/1000 mg = 1

How many grams? Convert F SO2 from mg/L to g/gal 65 mg/L*(3.785 L/1 gal)*(1 g/1000 mg) = 0.246 g/gal

Add as Potassium Metabisulfite, (KMB) Potassium Metabisulfite is only 58% SO2 Conversion factor from SO2 to KMB = 1.7 0.246 g/gal * 1.7 = 0.418 g/gal KMB

We have 1000 gal of wine, so: 0.418 g KMB/gal * 1000 gal =

418 g Potassium Metabisulfite

How to Protect the Wine?Assume 1000 gal of winepH = 3.44No SO2 added yetPlan to bottle with RS

Potassium Sorbate Addition

Potassium Sorbate

Sorbate Target 200 mg/L sorbate

How many grams to add to our tank?

200 mg/L *(3.785 L/1 gal)*(1 g/1000 mg) = 0.76 g/gal sorbate

Potassium Sorbate is only 74% sorbic acid

Conversion factor: 1.35

(0.76 g/gal)*1.35 = 1 g/gal

1 g/gal * 1000 gal = 1000 g potassium sorbate

Potassium Sorbate

Gut checkPotassium metabisulfite:Adding 423 g to 1000 gal wine

Potassium sorbate:Adding 1000 g to 1000 gal wine

Does this seem right?

Impact on Cold Stability!Adding more Potassium

Potassium Sorbate

Weight! For bench trials, need to weigh ± 0.01g0 – 500g capacity

For additions of SO2 and Sorbate, need to weigh ± 1 g0 – 2 kg capacity

Gut Check

Material 1 cup weighs?PotassiumMetabisulfite(Powder)

341 g

Potassium Sorbate

103 g

Sugar, granular 200 g

BlendingSensory Impact Requires Blending

Trials

Chemical Composition CalculationAcidAlcohol

Blending 2 Wines - Alcohol

Pearson’s Square

a

b m-a

b-mm

11%

Blending to target 12% alcoholWine “a” has 11% alcoholWine “b” has 14% alcohol

14%

12%14-12=2 2 Parts A

12-11=1 1 Part B

3 Parts Total

Blending 2 Wines - TA

Target 6.5 g/L

a

b m-a

b-mm

Wine “a” has 7.1 g/L TAWine “b” has 8.9 g/L TA

Blending 2 Wines

Target TA 6.5 g/L

a

b m-a

b-mm

Wine “a” has 5.4 g/L TAWine “b” has 8.9 g/L TA

5.4

8.9 1.1 Parts B

2.4 Parts A6.5

3.5 Parts Total

Blending for TA, cont’d Need to use 2.4 Parts A, 1.1 Part B

Total Volume Desired = 250 gal

Determine proportions 3.5 total parts 2.4 parts A/3.5 total parts = 0.686 A 1.1 part B/3.5 total parts = 0.314 B The whole is the sum of its parts A+B = 1 0.686 + 0.314 = 1

How much of Wine A and Wine B to make 250 gal blend?

A: 250 gal*0.686 = 171.5 gallons of wine A B: 250 gal*0.314 = 78.5 gallons of wine B

Sugar Additions Large sugar additions increase wine/juice volume

500 gal of juice at 18 Brix, desired to have 22 Brix

Need to add ~4% sugar, or 40 g/L

40 g/L * (3.785 L/1 gal) = 151.4 g/gal

151.4 g/gal * 500 gal = 75,700 g = 75.7 kg

75.7 kg * (1 lb/0.454 kg) = 167 lb sugar (!)

Sugar Additions How much additional juice volume will result?

167 lb sugar = 75.7 kg sugarDensity of CRYSTALLINE SUGAR ≈ 0.85 kg/LDensity of DISSOLVED SUGAR ≈ 1.7 kg/L

75.7 L crystalline sugar/1.7 kg/L = 45 L dissolved sugar

Final juice volume is increased: 500 gal + 45 L/(1 gal/3.785 L) = 512 gal

SummaryYes, online calculators are available

Proficiency in winemaking calculations Reduce chance of mistakesMake additions to juice/wine with confidence

Online Calculator

http://vinoenology.com/

Questions

Thank You!

HANDOUTS

Free SO2 and pH chart

Unit conversions/rules of thumb

Typed example calculations