1. 2010 Home Winemaking Class
Advanced Topics
Linda Donovan
541.621.1589
lindasuedonovan@aol.com

2. Introduction
 UCD Grad
 Making Wine for 19 years
 In Rogue Valley for 10 years
 Started Pallet Wine Company in Medford
 This class will walk you through the process of making 5
gallons of finished (drinkable) wine while addressing
advanced topics and analysis.

3. Class Outline
 Grape Development and Composition
 Grape pests and identification
 Grape and Must handling procedures - adjustments
 Winemaking Procedures
 Microbiology
 Fining and Filtering
 Stabilization
 Oak and Winemaking
 Analysis Techniques
 Tasting – good and bad wines

4. Grape Development
 Better grapes = better wine
 Berry undergoes rapid cell division and acid accululates
 Growth rate decreases and the berry “rests”
 Veraison: Sugar (sucrose) translocated into the fruit, acids
degrade and color begins to appear. Berry expands, flavor and
aroma compounds build up.
 Berry begins to dehydrate due to water loss and sugars/acids
get concentrated.

5. Sugars in Grapes
 Unusual, high levels of sucrose for fruit
 Glucose (6-carbon sugar) and Fructose (5-carbon sugar)
 Early= higher levels of glucose than fructose
 Mid = 1:1 ratio
 Late = higher levels of fructose than glucose
 Fructose much sweeter than glucose
 Yeast have a harder time with fructose (over ripe fruit)
 Can differ by variety ( Chardonnay is an example of high fructose variety)

6. Acids in Grapes
 L-Tartaric and L- Malic = 90% of acid in grapes
 Tartaric uncommon in plants, malic is common
 More vigor = reduced acid and higher pH
 Acids increase in concentration until veraison, then decrease as
sugar accumulates. Malic decreases more rapidly in warm
climates.
 Cool climate = higher acid at same sugar concentration as warm climate.
 Hot climate = no malic acid at harvest
 High Tartaric acid varieties = Reisling
 High Malic acid varieties = Malbec and Pinot noir

7.  Tartaric acid exists as a free acid (initially) and, over time,
combines with cations predominately K+. Can combine
with Ca++ and form a salt = calcium tartrate.
 Sticks to equipment
 Can change pH and TA
Good to know levels of Malic Acid at grape stage to aide with
MLF decisions

8. Phenolics
 In white grapes, lower total phenolics and no anthocyanins
(color)
 In red grapes, phenolics very significant group of organic
compounds
 Color of wine
 Taste
 Aging properties
 Most phenolics (red and white grapes) are in skins, some in
seeds
 More concentrated in cooler climates

9. Cultural and Climatic Influences
 Any factor affecting grapevine growth and health will influence
ripening.
 HighYield
 Increase may reduce the ability of the vine to mature the fruit or it’s potential
to produce subsequent crops.
 In France, yield is viewed so important to quality, maximums have been set
for Appellation Control regions.
 Can be “offset” with improved fertilization, irrigation, pest control, etc.
 Low Yield
 Not necessarily improve quality
 Prolong shoot growth and leaf production
 Increase shading
 Depress acidity
 Produce larger berries = skin: flesh ratio

10. Sunlight
 Single most important climatic factor affecting berry
development.
 Promotes anthocyanin synthesis
 Essential for flavonol synthesis (phenolics- tannins)
 Grassy, vegetative and herbaceous aromas are reduced by sun
exposure.
 Sauvignon blanc, Semillon, Cabernet franc

11. Temperature
 Influences enzymatic activity in grapes= speeds up ripening
 Too hot = slows/stops

12. Grape Pests that Affect Wine Quality
 Birds and Bees
 Remove the crop
 Compromise the crop
 Bees “get in”
 Acetobacter takes hold

13. Powdery Mildew

14. Botrytis Bunch Rot

15. Botrytis can be desirable in some
styles of winemaking

16. Virus

17. Mealybugs

18. Concerns of Making Wine from Mold Infected Fruit
 Risk of moldy or compost type aromas
 Aroma loss or alteration
 Rapid must oxidation
 Problematic Fermentations due to infection
 Alteration of must color (browning)

19. Ready to Pick!!!!

20. Grape and Must Handling-
Adjustments
White Wine:
Sugar 22-24 degrees Brix
Titratable Acid = 6.5 – 8 g/L
pH less than 3.6
Red Wine:
Sugar 23 – 25 degrees Brix
Titratable Acid = 6 – 7.5 g/L
pH less than 3.7

21. Sugar Adjustments
 ºBrix * .55 = final % alcohol
 Want over 12% alcohol for stability
 Want less than 15% to ensure fermentation completeness
 Need to adjust:
 To bring sugars down:
 C1V1 + C2V2 = C3V3
 C = CONCENTRATION
 V = VOLUME
 Diluting sugars also dilutes acids and flavors – correct for acid

22.  To bring sugars up:
 Add sugar- sucrose (table sugar) beet or cane is fine -
The formula to use is:
S=0.125(v)(B-A)
Where S = the amount of sugar in pounds to add
0.125 = the amount of sugar in pounds needed to raise 1
gallon of juice 1 Brix degree
v = the volume of juice in gallons
B=desired final Brix value in degrees (usually 22)
A=current measured Brix value in degrees
For example: Your juice measures 17.5 ° Brix, and you have 10
gallons of juice.
You want a final Brix of 22 °. So,
S=0.125(10)(22-17.5) or S=5.625 lbs.
This means you need to add just less than 6 pounds of sugar
to your juice prior to fermentation to get the desired Brix
level.

23. Acid Adjustment
 To bring acid up:
 Add tartaric acid in g/L
 1 g/L tartaric acid increases TA by 1 g/L
 To bring acid down:
 Add potassium carbonate
 .62 g/L will reduce TA by 1 g/L

24. pH adjustment
 No “formula”
 Variety, vintage and buffering capacity
 1g/L raise in TA lowers pH by .1
 Important for picking decisions

25. Nitrogen Adjustments
 Important for yeast metabolism
 Amino acids
 Especially for compromised grapes
 Added as ammonia (DAP)
 Added as Superfood™
 Fermaid K™
 Contain yeast hulls, ammonia and vitamins
 Does have sensory considerations
 Referred to as Free alpha Amino Nitrogen or FAN
 Need to supplement when levels fall below 140 mg/L
 Can add 100 mg/L without testing

26. Enzymes
 Pectic Enzymes
 Break down pectins in skins and help with pressing
 Release flavors in skins
 Color X
 Settling
 Filtering

27. Add Sulfur Dioxide (SO2)
 Kills “bad” bugs
 Our yeast not as sensitive
 Prevents browning
 Protects juice and wine
 Expressed in ppm
 We will add 45 ppm to our juice using Campden tablets
 1 tablet per gallon = 75ppm increase
 5 gallons at 0ppm = add 3 tablets

28.  Using Potassium Metabisulfite:
 ppm increase * liters / 576 = grams of KMBS to add
 Using a 6 % solution:
 = 6 grams per 100 mls
 = 60 grams per Liter
 = 60,000 mg per Liter
 Volume to adjust * increase/solution

29. Sulfur Dioxide = SO2
 Widely used in food and wine industries
 Chemical antioxidant and inhibitor of microbial activity
 Prevents browning
 Several compounds bind with SO2
 Acetaldehyde
 Sugars
 Pigments

30. Bound vs. Free SO2
 SO2 in wine occurs in two forms (species) bound and free
 Sum of Bound and Free = total SO2 (legal limits for)
 Rate of binding of SO2 is:
 pH dependent
 Temperature dependent
 Wine dependent
 Bound SO2
 Constantly increasing over time
 Free SO2
 Constantly decreasing over time

31. Molecular SO2
 Most important antimicrobial agent
 Within the pH range of wine and juice, the amount of free
sulfur dioxide in the molecular form varies considerably.
 Most winemakers aim for a .5 - .8 mg/L molecular form.
 DEPENDS ON pH
 Can be estimated using free SO2 measurements

32. Making White Wine

33. Pressing first
 Transfer and sort grape clusters into press
 No leaves
 No moldy grapes
 Spiders. Earwigs and dirt = OK
 Press grapes until as dry as possible into two clean 5 gallon
buckets
 Press slowly – too slow= low yield, too hard= bitter tannins from
seeds, stems and skins
 Make adjustments now

34. Settling
 Keep as cool as possible
 Allow to settle overnight in cool place- don’t move around
 Rack clear juice into 5 gallon carboy plus other glass
container- fill ¾ full only!
 Put fermentation lock, breather cap on top.

35. Add Yeast
 For white wine, we are using Champagne yeast
 Need to hydrate and acclimate yeast
 Wait a couple days to see bubbles
 Monitor Brix and temps- temps go up fast!
 Smell often
 Will get very frothy
 Keep clean
 Top up container (s) near end of fermentation 0Brix
 Keep flies out but let gas out- can explode if sealed

36. Allow to finish and age
 When wine is “dry” , or when wine tastes good to you= time
to stop and protect wine.
 Will begin to clarify
 No CO2
 No Air!
 No heat

37. If wine is “done”
 Rack off solids
 Add SO2 at a rate of 50 ppm
 Top carboy
 Replace breather bung with a solid bung
 Keep cool
 Start thinking about bottling!!!

38. Stabilize prior to bottling
 Tartrates will precipitate and form “wine diamonds”
 Proteins will form a haze
 Tartaric acid stabilization= get wine cold for 2 weeks (32
degrees F) and allow process to happen in carboy and not in
bottle
 Proteins need a little bentonite to pull them out of solution
 Just for looks of a clear wine
 Add about 10 grams of bentonite and allow to settle.
 Rack once more and bottle

39. Ageing, Stylistic Options and Finishing
 Oak Chips – use carefully
 Sur Lies (on lees) stylistic
 Blending
 More acid/Less acid
 ML Fermentation
 Bacterial Fermentation
 Malic acid to Lactic Acid
 Stabilizes the wine
 Creates Butter Flavors
 pH, temp and competition issues

40. If wine is sweet or not through ML,
must filter to avoid fermentation in
bottle.
Or drink it fast!!
Check S02 once more and make additions based on pH

41. SO2 and pH
 Low pH requires much less sulfur dioxide (SO2) to be
“protected”
 pH 3.1 = 15 ppm
 pH 3.3 = 20 ppm
 pH 3.5 = 25 ppm
 pH 3.7 = 35 ppm
 pH 3.9 = 40ppm
 This is the amount of SO2 that is present at bottling
 Will lose a lot while transferring into bottles

42. Bottling
 Transfer wine into clean glass (rack)
 Use Nitrogen to displace air in bottle
 Avoid Oxygen!!
 Closure
 Capsule
 Label

43. Red Wine Making
A little different than whites

44. Process
 Pick
 Destem
 Into fermenter
 Adjust sugar, acid… if necessary
 Keep warm
 Add yeast
 Hydrate like white wine
 Begin to monitor

45. Punch Down
 Keep Cap wet and clean
 Distribute Heat
 Allow air in
 Extract tannins
 Not too much
 Taste often

46. Press
 Drain wine first
 Transfer skins and seeds to press
 Gently press
 Wine will be sweet
 Wine will be tannic
 Add press wine back to free run

47. Allow wine to settle
 Rack off heavy solids
 Continue to monitor
 Will begin second fermentation (naturally)
 Keep warm and topped up
 Smell often
 Add a little oak
 Allow to age until it tastes good!

48. Finishing and bottling Wine
 When wine is “ready”
 Blending
 Fining – if too bitter
 Egg whites
 Milk
 Gelatin
 Stabilize tartaric acids
 Know your pH and adjust SO2 accordingly

49. Next Time:
Microbiology
Fining and Filtration
Stabilization
Oak and winemaking
Analysis Techniques
Tasting!!!!

50. Microbiology
 Yeast –
 Good
 Wild vs. Engineered
 Bacteria
 Good
 Bad
 Acetobacter
 Lactic acid bacteria
 Mold – problem in beginning
 Other - EtOH

51. Fining and Filtering
 Process of clarifying and purifying
 Added to the wine settles to bottom
 Reacts with substance being removed
 Each fining operation should be proceeded by bench trial
 Can remove several compounds (flavor)
 Can contaminate wine by addition
 Can result in wine loss (additional racking)

52. Gelatin
 Reduce tannin in astringent reds
 Reacts with tannins through hydrogen bonding
 Dose rate of .05 to .15 grams per Liter
 Very easy to work with
 Hydrate in water and stir into wine

53. Isinglass
 Made from the swim bladder of certain fish
 Made almost entirely of collagen
 Very strong + charge to bind with - tannins
 Used to remove phenolics and bitter tannins
 Rather difficult to prepare but great results
 Brilliant and soft finish
 Rates of .02 to .1 gram per Liter

54. Milk and Casein
 Traditional for white wines to remove bitterness, harshness,
off flavors and lightening color
 Skim milk (or need to remove the surface cream)
 Powdered milk
 Rate of up to about 1%
 Casein needs to be made alkaline prior to adding to an acidic
wine.
 Dissolve casein in half its weight in potassium carbonate
 Rate of about .05- .3 grams per Liter

55. Egg-white or albumen
 Used to remove harsh tannins
 Very popular method
 Break eggs into aluminum bowl and add a pinch of salt. Wisk
eggs (not too foamy) and pour into mixing wine.
 Usual dose is one to three eggs per 200 liters of wine.

56. PVPP
 Poly-vinyl -poly –pyrrolidone
 Synthetic material
 Used in white wines to adsorb phenolics
 Used to correct for pinking and browning
 Insoluble in wine
 Very $$
 .2 to .5 grams per liter

57. Fining trials
 Use a bench trial to determine rate
6% solution
100 mls of wine to treat

58. Filtering
 Different pore sizes for filtration
 10 micron = clarify
 5 micron = polish
 1 micron = prefilter
 .45 micron = sterile filtration
 Absolute vs. differential

59. Oak and winemaking

60. Analysis Techniques

61. Measuring Sugar
 Refractometer
 Measures the bending of light
 Use until alcohol is produced
 Cost about $30 (look on eBay)
 Great to take into the vineyard
 Hydrometer
 Measures specific gravity – how thick
 Different scales
 Brix scale = -2 to 30
 Need about 150 mls per test (can pour juice back into
fermenter)

62. Sugars
 CliniTestTablets
 Easy to use- made to measure sugar in urine
 Very accurate in white wine
 Red wine needs to be decolorized for easier reading
 Use carbon or pvpp
 .5 mls of sample (5 drops) and 1 pill. Sample gets hot when
reaction occurs.
 Orange= sweet
 Blue = dry

63. pH
 Test strips range from 2.5 – 4.5
 Small hand held = $20
 Important to know pH

64. Titratable Acidity (TA)
 Acid test kits
 Reported in g/L or g/100ml
 6.5 g/L or .65g/100 ml
 Important to degas sample

65. SO2
 Tirets test kits at Grains Beans etc.
 Nielson Research Corporation
245 South Grape Street
Medford, OR 97501
(541)770-5678

66. Malo Lactic Fermentation
 Will stall if wine gets too cold and finish in the spring
 Will see bubbles in wine while fermenting
 Should take about 8 weeks to complete
 Can test with paper chromotography

67. Misc. Analysis
 Volatile Acidity (VA) = amount of vinegar
 Hydrogen Sulfide (H2S) = stinky, rotten egg
 Alcohol (Ethanol)

68. Making a Port Style wine
Eliminates the need for filtering
Alcohol protects against microbe growth
Use same formula as sugar dilution:
C1V2 = C2V2
C= concentration (sugar or alcohol)
V = Volume

69. Adding sugar and alcohol
 If wine is “ dry” add about 6 pounds of sugar to 5 gallons of
wine (add less if wine is a bit sweet)
 Add about ½ gallon of high proof alcohol
 C1V1 + C2V2 = C3V3

70. Tasting Wines
 Color
 Clarity
 Aroma
 Taste
 Finish

71. GOOD LUCK!!!
See you next year