Wine

Lecture No.7
Food and Nutrition
Lecture content
Alcoholic beverages - definition

Wine - definition; Winemaking, Vinification, Oenology

Geographical areas of vine cultivation

Processing of grapes into wine - common procedures

Production of white wines

Production of red wines

Production of rose wines

Wine care and aging procedures

Diseases and defects of wine

Special wines
•Sparkling wines
•Liquor wines
•Sweet (dessert) wines
Alcoholic beverages
• Categories of products containing from 2 to 15% vol of alcohol
• They are produced by alcoholic fermentation caused by yeasts from
starchy or sugary raw materials
• Raw materials can come from fruits, vegetables, grains or any other raw
material that contains a sufficient amount of sugar to carry out alcoholic
fermentation
• The most commonly used raw materials are: corn, barley, oats, various fruits,
potatoes, sugar beet and molasses

ALCOHOLIC FERMENTATION:

𝐶6𝐻12𝑂6 𝑔𝑙𝑢𝑐𝑜𝑠𝑒 → 2𝐶2𝐻5𝑂𝐻 𝑎𝑙𝑐𝑜ℎ𝑜𝑙 𝑒𝑡ℎ𝑎𝑛𝑜𝑙 + 2𝐶𝑂2 + ℎ𝑒𝑎𝑡

Wine
Wine
• Product with an actual alcohol strength of at least 8.5% vol., obtained by full or
partial alcoholic fermentation of fruit juice or must (Must =mixture of liquid
ingredients, pulp and skin)

Winemaking
• Activity that deals with the production of wine, grape and wine products.
Numerous activities from the selection of grapes to the bottling of wine

Vinification
• A series of operations by which grapes are processed into wine, which consists
of: harvesting grapes, delivering grapes to the cellar, pressing and crushing
grapes, sulfiting the grapes and must, alcoholic fermentation, decanting the
wine, care and maturation of the wine, and bottling wine into bottles

Oenology
• The science of vine cultivation, wine production and storage
Winemaking
Two general types of processing:
• Production of still wine- without carbonation (CO2)
• Production of sparkling wine- with carbonation (CO2)
• Red wine, white wine, rose wine
• Grape – plant: Vitis vinifera
• Fruit wine: made from a variety of base ingredients (other than grapes).
• Apple juice- cider; pear cider- perry
• In areas with cool climate (North America and Scandinavia).
• In subtropical climates (Africa, India, Philiphines) wine could be made
from bananas
 History of wine cultivation and
processing Expansion
through
In the 17th
century,
cultivation
Palestine and began in
The first Syria to Egypt South Africa
archaeological and and
data on wine Mesopotamia California,
production date and later and in the
back to 7500 throughout the 19th century
years ago Mediterranean in Australia

The development In the 16th Today,

of winemaking century, vineyards are
begins in the area European located
of the southern colonizers mainly in
Caucasus brought the moderate
(northwestern wine to climate
Turkey, northern Mexico, zones
Iraq, Azerbaijan Argentina and
and Georgia) Chile
Geographical areas of vine cultivation
geographical area with
similar climatic and
pedological conditions;
Wine region affects the main qualitative
characteristics of grapes
and wine

geographically limited area with

Viticulture subregion similar climatic and pedological
conditions, similar assortment

Very uniform climatic and pedological

Vineyard
features and assortment

Vineyard geographically limited parts of the vineyard in

positions terms of climate, soil, altitude and variety
Processing of grapes into wine
• The quality of grape determine the quality of wine more than any
other factor.
• Grape´s quality: variety, weather during growing season, soil,
minerals, acidity, time of harvest – terroir

Cluster: stemm+ berry

Berry: pulp+ skin (powder=wild yeast cells)

• During the ripening of grapes, there is a decrease in total acids, an

increase in the sugar content, and the formation of colour and
aroma substances
• Harvesting the grapes
• Mechanically or by hand
• The decision to harvest is typically made by winemaker according to the level of
sugar, acids and pH value of the grapes
• Technological maturity
Processing grapes into wine
• The first stage of processing:
• Destemming: process of separating stems from the grapes
• Stems have a relatively high tanin content
• Lowering the development of tannins and vegetal flavors in the resulting
wine
• Tannins: class of astringent, polyphenolic biomolecules
• The second stage of processing
• Crushing: process of gently squeezing the berries and breaking
the skins to start to liberate the contents of the berries

• MUST: A mixture of solid (pulp+skin) ingredients and liquid

(juice) ingredients

White wine:
alcoholic Red wine:
fermentation in juice alcoholic fermentation in
must
• Red wine: made from the must (pulp+ liquid) of red grapes
• Fermentation occurs together with the grape skins, which give the
wine its colour
• White wine: made by fermentation of juice (liquid fraction)
• Crushing grapes: extract a juice + skins
• Pressing- extracting juice with minimal contact with the grapes' skins.
• Rosé wines: either made from red grapes where the juice is allowed to
stay in contact with the dark skins long enough to pick up a pinkish colour
=maceration
• or (less commonly) by blending red wine with white wine
• White and rosé wines extract little of the tannins contained in the skins
Pressing
• Red wine: the must is pressed after fermentation
• Separate the skins and other solid matter from the liquid
• White wine: the liquid is separated from the must before
fermentation
• Fermentation in juice
• Rose wine: the skin may be kept in contact with juice for shorter
period to give color to the wine
• Pressing afterwards
Fermentation
• Yeast (Saccharomyces cerevisiae)- microorganism
• may occur naturally as ambient yeast on the grapes. Yeast normally present on the
grapes - powdery appearance. They give unpredictable results of fermentation
(failure for the fermentation to go to completion, some sugars remain unfermented)
• may be added in cultivated form (more often)
• During fermentation (which often takes between one and two weeks), the yeast cells
feed on sugars in the must and multiply, converts most of the sugars from grape juice
into alcohol ethanol and carbon dioxide
• The carbon dioxide is lost into the atmosphere
• The temperature during fermentation affects both the taste of the end products as well
as the speed of fermentation
• Red wines: temperature: 22-25 oC
• White wines: 15 – 18 oC
Production of white wines
• Pressing the mixture of solid and liquid ingredients (must)
• Pressing: act of applying pressure to grapes in order to separate
juice from grape skins
• Mechanical presses → juice (liquid part of mixture)- to fermentation
• Free-run juice: higher quality
• The amount of sugar in the juice determines the amount of
alcohol in the wine (sugar x 0.6= vol % alcohol)
• Juice : 17-25% sugar
• Sometimes: cold maceration - highlight the varietal aroma or
intensity of colour of white wines; for grapes of aromatic varieties
 Improvement of juice before
fermentation

Modification
• Protection of juice from oxidation
of the
• Enzyme inactivation • Addition of sugar,
chemical
Sulfurization • Inactivation of natural microflora correction of acidity
composition
(yeasts, bacteria, moulds) of the juice
• Precipitation of turbidity particles

• Mixing juices of two or

• Slowing down undesired Coupaging more grape varieties=
Cooling
oxidation processes coupage

Precipitation • Removal of turbidity particles

Alcoholic fermentation
• Fermenters: wooden barrels, metal or concrete tanks, cisterns
• 20% empty space – removing of CO2
• It starts after 24 hours - lasts 12 days

Spontaneous:
conducted by
Controlled- conducted
natural microflora
by
on grapes
addition of selected
yeasts
Alcoholic fermentation

Initial phase Phase of intensive Phase of slow

fermentation fermentation
aerobic – with the presence anaerobic - without the
of oxygen, presence of oxygen,
growth and reproduction of sugar is broken down and Lasts 10-30 days
yeast cells alcohol is produced
intensive fermentation: 4-8
days
Production of red wines
• Extraction of the desired phenolic compounds and
colouring matter
• Anthocyanins - colour substances (located in the skin)
• Alcoholic fermentation in a must (mixture of solid and
liquid particles)
• Specificity:
• maceration
• malolactic fermentation
Maceration
• The process of gradually extracting individual ingredients from the
solid parts of grapes into liquid part (primarily from the skin, but
also from the seeds)
• In the production of red wines, the extraction of phenolic
substances (anthocyanins and tannins) that participate in the
formation of the structure and colour of the wine is primary.
• During maceration, aromatic substances, nitrogenous compounds
and minerals are separated
• Colour substances are responsible for the colour intensity of red
wines, while tannins affect the harmony and taste of the wine
• The duration and method of maceration are of great importance for
the quality of red wines
• It can be carried out before and after fermentation, BUT it is most
often carried out in parallel with fermentation
Malolactic fermentation

Reduction of acidity
Better wine stability
Malolactic bacteria Changed aroma
have the ability to act
at a high concentration
Conversion of malic of ethanol and acids
acid to lactic acid
leading to a reduction
in acidity and the
production of aroma
and flavour
compounds
 Wine care and aging procedures
• Aging of wine: achieving stability, development of aroma and
texture of wine
• Physico-chemical changes
Coupage
(mixing, pairing,
typification - Filtration
Refilling the wine, grape, (plate
tanks must) filters)

Wine Stabilization and Aging

decanting clarification:proteins, (before and
(open and colours, after
closed microorganisms, bottling)
systems) tartaric acid salts
Bottling of wine
Bottling
•The wine that is bottled must be stable to proteins, tartrates and
microbiologically stable.
•Automatic or semi-automatic fillers (empty space)
•Top quality wines - sterile filling

Bottle capping (caps: cork, crown, screw, silicone)

Adding a plastic or aluminium capsule – heating for a tight
seal
Labelling the bottle (main and back label, banner)
 Wine of unsatisfactory quality
Wine diseases (due to the activity Wine fault (chemical and physical
of microorganisms) changes, due to presence of foreign
• Acidity: acetic bacteria; wine substances or inappropriate
turns into vinegar technology)
• Wine flower: yeasts; white-gray • Wine browning – unwanted
membrane on the surface oxidation; enzymatic
• Mucilage: bacteria; oily • Presence of heavy metals – Fe,
consistency Cu, Al; vineyard or dishes
• Cork taint - set of undesirable
smells or tastes found in a bottle
of wine, specially spoilage that
can only be detected after
bottling, aging and opening
SPECIAL WINES
• Wines obtained from fresh grapes, must or wines that have
undergone normal procedures during or after production
• The properties come not only from the grapes but also from the
applied technological production procedures
• This category includes:

Sweet wines with

Carbonated a larger amount
Sparkling wines Liqueur wines
wines of unfermented
sugar
 SPARKLING WINES
• Special wines that, in addition to other ingredients, are characterized
by an increased amount of carbon dioxide that is created exclusively
during the process of secondary alcoholic fermentation
• As a result of the dissolved carbon dioxide, the pressure in the closed
bottle is increased and at a temperature of 20 oC it is at least 3 bars (6
bars)
• Primary fermentation - base wine (9.0-11.5 vol% alc) + Secondary
fermentation – for CO2 formation
• According to the method of production:
Classic method - secondary fermentation in the bottle (Champagne
method)

Charmat method - secondary fermentation is carried out in large tanks

The classic method of secondary fermentation
in the bottle - the Champagne method
• The wine is fermented first in the barrel and then undergoes a second fermentation in the bottle
after the addition of tirage liquer = yeast, nutrients for the yeast, and sugar
• Yeast precipitate (lees) must then be removed
• The process to remove lees is called disgorging
• This begins with riddling (remuage): the bottles are turned with the neck downwards and lightly shaken to
move the lees to the neck of the bottle
• This is done in small steps where the bottle orientation gradually changes
• Finally, the inverted bottle necks are cooled so that the precipitation freezes to a small block of ice=
disgorgement
• The bottles are turned upright and the temporary closure (normally with a crown cap) is opened so that the
precipitate is pushed out by the pressure in the bottle.
• Then the bottle is filled to replace the missing volume, and fitted with a plain Champagne cork and wire mesh
• Historically the various stages were performed manually but the whole process is now automatic
for most wines
• In connection with the filling of the missing volume, it is common to add a certain amount of sugar
dissolved in wine to give the sparkling wine a smoother taste.
• Sugar addition is called dosage and the added liquid liqueur d'expedition.
 The classic method of secondary
fermentation in the bottle - the
Champagne method

Placing the
In the
bottles in
base Bottling – Secondary
special Bottle
wine – closing fermentation
racks in an Disgorgement – Adding capping -
adding with a - turning the
inclined removal of expedition metal Labelling
of tirage crown cap bottles and Aging
position sediment liqueur cap - the bottles
liquer in a stirring
(several (yeast cells) wire
(special horizontal (min. 5-6
months, mesh
yeasts + position months)
turning)=
sugar)
riddling
Labels on sparkling wines
Considering the sugar content, the labels on sparkling wines are as
follows:
brut nature: contains less than 3 g/l of reducing sugar

extra brut: contains less than 6 g/l of reducing sugars

brut: contains less than 12 g/l of reducing sugars

extra dry, extra sec: contains from 12 g/l to 17 g/l of reducing sugars

dry, sec: contains from 17 g/l to 32 g/l of reducing sugars

demi sec: contains from 32 g/l to 50 g/l of reducing sugars

doux: contains more than 50 g/l of reducing sugars

Considering the composition of grape varieties, the labels
can be:

Blancs de blancs (white of white) – chardonnay with fruity aromas

Blancs de noires (white of red) – from the black varieties pinot noir
and pinot meunier with aromas of dried fruit, wood and tobacco

Rose – processing of black grapes so that the white juice is allowed to

combine with the black skin for several hours
 Processing of sparkling wines by
fermentation in large tanks - Charmat
method

Both Both fermentations are At the end of

Faster, simpler
fermentations – carried out in strictly fermentation – Bottling
and cheaper
in large controlled conditions stabilization without loss of
way of
stainless steel (cooling) - double- and separation carbon dioxide
production
tanks walled tanks of sediment
 Sweet wines (Dessert wines)
• Sweet wines are wines whose common feature is that they contain a large
amount of unfermented sugar
• Wines from dried grapes are produced by drying the grapes and
producing juice, which is then concentrated and subjected to alcoholic
fermentation
• The difference between wine made from dried and overripe grapes is in
the alcohol strength

Wine made from

dried grapes has an Wine made from overripe
actual alcohol content grapes has an actual
of at least 9% vol
alcohol content of at least
12%
• Ice wine is a type of dessert wine produced from grapes that have been frozen in
vineyard
• The sugars and other dissolved solids do not freeze, but the water does, allowing for a more
concentrated grape juice to develop
• Matures in bottles for an additional three to five years
Thank you for your
attention!