Wine Making

1
Wine Making

• The adventures and trials of a chemist learning
  to make wine the Benedictine Way

2
Outline

• Something about myself
• Something about the chemistry of wine
• The genesis of my wine making and a look at its
  future.

3
Personal Information Education

• B.S. Chemistry, St. Procopius College (now
  Benedictine University) 1971
• M.S. and Ph.D., University of Illinois, Physical
  Chemistry 1980
• Doctoral Thesis Entanglements and Crosslinking
  in Polybutadiene

4
Personal Information Experience

• Clinical Chemist in Renal Research
• Melt Spinning of Liquid Crystal Polymers
• Electronics Design and Manufacturing
• Environmental Audits and Design for the
  Environment
• Formulations Chemist for Electronic Materials
• Currently Technical Conference Director for IPC
• Winemaker (year 2)

5
The Chemistry of Wine

• History
• Chemistry
• Personal experience
• The future

6
History

• Vitis Vinifera The grape. The word wine
  derives from vinus (wine)/vine (grape) (Latin),
  but may be traced further back to Greek.
• The grape is a relative of Boston Ivy and
  Virginia Creeper originally thought to be from
  Asia
• Alcoholic fermentation may date back as far as
  10,000 years. And grapes may not be the original
  source of the sugars fermented to produce
  alcohol.
• A possible origin of alcoholic beverages they
  are food which has spoiled, e.g. cheese.
• For years fermented drinks served as a source of
  clean liquid refreshment (compared with many
  sources of water) and as a relief from the stress
  of a hard life.

7
History

• In Greece, wine was considered a staple by 700
  B.C. (In Greek, the word for breakfast,
  akratidzomai, means to drink undiluted wine.)
• However, Italy proved so compatible to the grape,
  that sometime after 200 B.C., the Greek word for
  Southern Italy was Oenotria (land of the grape).
• After the fall of Rome (410 A.D.) and the
  dissolution of the empire in the dark ages, the
  knowledge of wine making and fermentation were
  kept alive in Europe by Christian
  communitiesprimarily the monasteries. (There are
  a variety of Islamic writings on wine,
  fermentation and distillation, although their
  extent is lesspossibly due to the ban on alcohol
  in Islam.)
• The first European grapes were successfully
  planted in California by the Franciscan order and
  the many wineries along the Mississippi got their
  start from the early French missionaries.
• Today California is the largest U.S. state
  producer of wine.

8
History

• Grape-based wines are often classified by either
  generic or varietal names region, although the
  wine may not be from that specific location, e.g.
  Burgundy, or grape type, e.g. Pinot Noir.
• Wine may be made from a variety of fruits or
  starch containing grains, e.g. Sake.
• Vintage refers to a wine made from grapes of a
  single year. (Blended wines of different years
  are generally not assigned a vintage.)
• A varietal wine may have a mix of grapes, but the
  primary grape will make up at least 75 to 85 of
  the total, e.g. Merlot.

9
The Top 10

• France
• Italy
• Spain
• United States
• Argentina
• Australia
• China
• South Africa
• Chile
• Germany

10
Some Chemistry

• Fermentation from the Latin fervere, to boil.
• The anaerobic process by which yeast reacts
  (eats) sugar to produce carbon dioxide and
  ethanol.
• First described in detail by Louis Pasteur

11
Some Chemistry

• C6H12O6 ? 2 C2H5OH 2 CO2
• C6H12O6 ? 2 CH3COCOO- 2H
• CH3COCOO- H ? CH3CHO CO2 (acetaldehyde if
  allowed to oxidize will yield vinegar acetic
  acid)
• CH3CHO NADH ? C2H5OH NAD (Nicotinamide
  adenine dinucleotide)

12
Some Chemistry

• All this occurs only in the absence of oxygen.
• In the presence of oxygen, the reaction proceeds
  all the way to carbon dioxide and water as end
  products aerobic respiration. (In humans this is
  the Krebs cycle carbon dioxide and water.)
• In the presence of oxygen AND bacterial
  (acetobacter) contamination acetic acid,
  vinegar, is formed from the ethyl alcohol.
• Generation of high-energy molecules as part of
  anaerobic respiration the energy cycle for the
  yeast. (In humans the end product is lactic
  acid.)
• Yeast eats sugar and produces waste alcohol.
• Note the above is a simplified view of a
  multi-step biochemical process with many side
  reactions.

13
A Little More Chemistry

• The simplest process of JUST sugar and yeast,
  allowed to react in the absence of air, would (at
  the simplest level) produce alcohol in the form
  of diluted vodka.
• This would deprive the world of the great
  opportunities for snobbery which are inherent in
  the culture of wine making (to say nothing of
  other alcoholic beverages such as single malt
  scotch, tequila, bourbons and even, shudder,
  light beers).
• So lets talk about the various (simple) things
  that allow humans to move from simple chemical
  thoughts to the madness of wine tasting

14
Taste

• Grape Type
• Variety
• Location, especially soil quality (French
  Terroir)
• Weather conditions
• When the grape is picked, e.g. in German
  spatelese or auslese wines.
• Skins or no skins red, rose or white
• Long skin contact red
• Short contact time rose
• Filtered juice white

15
Taste

• Blended or not using one season's crop or
  multiple seasons.
• Pre-fermentation natural yeast or added yeast
• Bulk fermentation natural yeast or added yeast
• Temperature of fermentation
• White wine 18 20 C
• Red wine up to 29 C
• Beaujolais below 20 C preferably around 10 C

16
Taste

• Sugar natural or added changes the level of both
  alcohol and sweetness.
• Length of fermentation to the bitter end or
  halted and stabilized
• Temperature shocked
• Alcohol doped
• Sulphite killed
• Filtered to remove all yeast/bacteria
• Aging
• Bulk aging
• Bottle aging
• With or without settled yeast (the lees)
• Temperature
• Type of container

17
Taste

• Added flavors Oak, tannin, glycerol, raisins,
  etc.
• Fortification added brandy or spirits
  (originally developed to preserve wine in sea
  voyages)
• Other fermentation processes
• Bottle fermentation sparkling wines
• Whole grape fermentation or carbonic maceration
  (fermentation of un-crushed grapes) to produce a
  distinct fruit flavor, e.g. Beaujolais.
• Malolactic fermentation (bacteria based)
  converting malic into lactic acid done either
  during primary fermentation or afterwards to
  produce a smooth buttery taste.

18
Chemistry Side Effects

• Other products of the fermentation process
• Aldehydes
• Ethyl Acetate
• Acetic acid (acetobacter contamination)
• Ketones
• Mercaptans
• Fusel oils (higher weigh alcohols)
• Thiols
• Di-carboxylic acids
• Aromatic compounds such as terpenes, phenols and
  norisoprenoids that add bouquet to the wines.
• Added sulphite (usually in the form of potassium
  meta-bisulphite) as a sterilizing agent.
• At any stage of the game, cross contamination by
  bacteria or other yeast strains may highjack
  the process and result in spoilage.

19
Personal Experience

• St. Procopius Monastery (124 years old)
• The grapes
• Process
• Results

20
St. Procopius

21
The Vineyard at St. Procopius

• Monastery records indicate that the vineyard was
  planted somewhere around the turn of the century.
• The exact date is not known although wine
  production is mentioned in letters from the early
  part of the 20th century.
• Thus the vineyard has been in continuous
  cultivation for 100 years.
• Three grape varieties
• Concord
• Niagara White
• Carco Red

22
The Vineyard at St. Procopius the Early Days
23
The Vineyard at St. Procopius Today
24
The Vineyard at St. Procopius

• Concord the grape juice grape
• Niagara White a hardy white grape common in
  Illinois wineries.
• Carco Red ?

25
St. Procopius Carco Red

• There is no specific strain called Carco Red.
• However research with the University of Illinois
  and wineries in the area yielded the following
• Historically, the vine for Carco wine can be
  traced to Madeira (Portuguese, northwest of
  Africa).
• Most probably it came via the Iberian Peninsula
  to Madeira and was field blended with Malvasia
  grapes and taken to Corsica.
• It is also cultivated in France under the name
  Vermentino
• In Spain, it would be known as Vin Santo
• This vine is most probably a variant of
  Vermentino/Vin Santo brought here from either
  from France, Spain or Corsica. 

26
How I Came to be Involved

• Alumni of St. Procopius College (way back when)
• Still identify with monastery and know many monks
  there.
• Through the lay program at the monastery, I
  learned that the vineyard and orchard were still
  active (last of the 1000 acre original farm)
• Volunteered to help and in return asked to be
  taught how to make wine (no wine had been made
  for two years when I started)
• During my first year half of the grapes were
  given to food pantries. Half I got to play with!
• In my second year my wine making has expanded in
  size and scope to include wine and cider making
  using the apple orchard.

27
The Wine Making Process as I Learned It

• In the early Spring, vines are pruned and weeded
  to reduce the number of grape clusters increased
  grape size.
• In late summer as grapes appear, care must be
  taken to protect grapes from raccoons and deer
  (electric fence).
• Grapes are picked when they have no trace of
  sourness.
• Vines are harvested as they mature, with grapes
  being stored in a walk-in cooler. (In 2007, we
  picked about 800 poundsof which 400 were made
  into wine. In 2008 we harvested almost 2000
  pounds of which nearly 1000 were made into wine.)
• When all grapes have been harvested they are
  crushed mechanically using a hand powered crusher
  or the old fashioned way by stomping. (Some
  grapes were also used to make a Beaujolais style
  wine carbonic maceration with no crushing
  involved.)

28
The Wine Making Process as I Learned It

• Potassium Metabisulphite is added to the crushed
  grapes (must) to reduce bacterial growth.
• In contact with the skins, the grapes pre-ferment
  from natural yeasts for one to two weeks or until
  the must is floating on the juice.
• At that time, the grapes are pressed and juice
  separated from the must.

29
Harvest
30
Harvest
31
Grape Cold Storage by Experimental Variable
32
Cleaning the Grapes
33
The Mechanical Crusher
34
Stomping
35
Pre-Fermentation Must Crushed
36
Pre-Fermentation Must Stomp
37
The Wine Press
38
The Wine Press
39
The Wine Press
40
Pre-Fermented Pressed Juice
41
Sugar and More Yeast
42
Filling the Jugs
43
Fermentation
44
Fermentation
45
The Variations We Experimented With

• In 2007 by changing the levels and types of yeast
  and ratios of sugar to juice, we ended up with 12
  variations on a theme.
• In 2008 we chose the most popular formula (Br.
  George's recommendation that I was too stubborn
  to accept the first time but input from our
  tasters proved him right) from 2007 and used
  experimental variables of
• Constant ratio of 4 gal juice, 1 gal water (7 lb
  sugar per gallon) with one package of Champagne
  yeast per 5 gal of the mixture.
• Grape type (all varieties including the wild
  grapes were separated by type)
• Pruning used
• Light prune
• Heavy Prune
• Prune with and with out weeding
• Crushing used mechanical or foot
• Bulk aging until bottling with and without
  contact with yeast lees

46
(No Transcript)
47
(No Transcript)
48
Other Wines for 2008

• Apple Wine
• Apple cider
• 1 lb sugar and package of champagne yeast per 5
  gallons.
• Small quantities of tannin, pectin enzyme, yeast
  nutrient and Vitamin C added.
• No stabilizers were added at bottling.
• Beaujolais style wine
• Remaining grapes in cooler were inoculated with
  71B-1122 Saccharomycus Cerevisiae and Champagne
  yeasts.
• They were allowed to crush under their own weight
  in a barrel saturated with carbon dioxide, i.e.
  carbonic maceration
• Primary fermentation lasted 3 weeks in cool
  conditions.
• Grapes were pressed and allowed to secondary
  ferment for 2 months.
• Wine was racked and stabilized by addition of
  stabilizers (KMBS, Potassium Sorbate and Vitamin
  C) and grain alcohol.

49
Results 2007

• 246 (0.75 l) bottles.
• 8 bottles of fortified wine also produced.
• 17 tastings by 8 tasters done during process
  as quality control.
• General conclusions
• Ratio of juice to water appears overshadowed by
  yeast although a high juice to water appears
  best.
• Use natural yeast if possible or added yeast with
  extra sugar.
• Decanting to remove sludge not needed.
• Based on tasting the decision was made to
  separate by grape type in the next year and
  compare heavily pruned (thin skin) with lightly
  pruned (thick skin) grapes. The 41 ratio of
  juice to sugar/water with Champagne yeast was
  picked as the best candidate formula.

50
Results 2008

• Approximately 450 bottles of wine are expected.
  (As of 1/23/09, 60 bottles representing the wild
  grapes, the white and rose grapes, the apple and
  the Beaujolais wine had been bottled.)
• 3 bottles of fortified wine have also been
  produced.
• Tastings by 5 tasters done during the process
  as quality control suggest
• The wild grapes have produced the best wines.
• The Carco Rose evokes strong feelings Some like
  it and some dont!
• The White Niagara and the apple are good but dry.
• The Beaujolais is rated good but has some vinegar
  overtones indicting the process needs to be
  tightened next year.
• For next year the decision to prune heavily or
  not will depend on the taste results from the
  Concords that are still aging.

51
The Future

• Work will start on the 2009 crop, pruning and
  weeding, in early spring.
• Bottling of the Concords should be complete by
  May.
• One wine tasting for the monks was done in July
  of 2008. An initial sampling of the early bottled
  wines was held for the monks in January 2009.
• As volunteers we continue to be at the disposal
  of the community and hope to continue to assist
  in preserving this Benedictine heritage.

52
References

• On Food and Cooking, Harold McGee
• Wines Their Sensory Evaluation, M. Amerine and
  E. Roessler
• The Wine Bible, Karen MacNeil
• Winery Technology and Operations, Yair Margallit
• Wine Chemistry, Yair Margallit
• The University Wine Course, Marion Baldy