Viticulture and Vinification Study Guide Flashcards
What 6 things does the grower or viticulturist confront decisions on?
vine training canopy management fertilization and irrigation harvest dates disease control the development of the vineyard in general
What do advances in viticulture aim to reduce?
The vagaries of weather and disease, and promote either the quantity or quality of wine.
When does the annual life cycle of the vine begin? When does this happen? What happens during this stage?
budbreak; occurs in March or April in Northern Hemisphere
the first small shoots and leaves will break through the buds left intact by winter pruning
What does “weeping” or “bleeding” refer to in regards to a vine? When does this occur? Before what stage in the vine’s life cycle does this occur? What average air temperature triggers this?
refers to the running of watery sap from pruned canes sometime in February (Northern Hemisphere)/August (Southern Hemisphere) when a vine emerges from dormancy
Occurs prior to bud break when average air temperature surpasses 50F
What hazard is the vine most vulnerable to during bud break?
frost
What happens between bud break and flowering.
The vine’s foliage continues to develop and small green clusters called embryo bunches form on the shoots by mid-April
What stage follows budbreak? How many weeks afterwards does this happen? What happens during this stage?
Flowering; embryo bunches bloom into small flowers for about 10 days, and the self-pollinating grapevine begins the process of fertilization, leading up to fruit set.
This occurs 6-13 weeks after bud break
What are the 3 main hazards to a vine during the flowering stage?
damaging effects of cold, frost, and wind
What stage follows flowering? What happens during this stage?
Fruit set; successfully pollinated embryo bunches grow into true grape clusters during fruit set- each grape is the product of individual fertilization.
What % of embryos successfully fertilize during fruit set to produce grapes on the cluster? What happens to the rest?
around 30%; the rest “shatter” falling from the cluster
What does “shatter” refer to in regards to a grape’s growth cycle?
Refers to the falling off of unfertilized embryos during fruit set
What are the berries like in regards to form and makeup leading up to veraison following fruit set?
hard, high in acidity, and low in sugar
What stage follows fruit set in the vine’s growth cycle? What happens here? What happens to the grapes in regards to color and chemical makeup?
véraison; the grapes begin to truly ripen, as sugars are moved from the leaf system to the fruit.
The grapes soften and change color-turning from green to red-black or yellow-green-and acidity decreases
Does véraison happen uniformly on a grape cluster or individually? What grape demonstrates this best?
Véraison happens on a grape to grape basis. Some grapes such as Zinfandel are notorious for uneven ripening.
What happens to the canes of a vine during véraison as the grapes ripen?
Canes ripen in tandem with véraison, as the stems on each shoot begin to lignify, accumulating carbohydrates to sustain the plant through the winter.
When are the grapes consider ready for harvest?
Once the grapes have achieved optimal balance of sugar and acid, they are ready for harvest.
What does vendange refer to?
the harvest
When does harvest occur in the Northern Hemisphere?
May start as early as August and last through the beginning of November
Which are harvested first generally, white grapes or red grapes?
White grapes if used for table wine. Late harvest grapes may hang longer than reds in isolated cases where they may hang on the vine until late November or December
What does physiological ripeness refer to?
refers to must weight and pH along with the ripening of tannin and other phenolics, the condition of the berry and its pulp, and seed lignification, which often requires longer “hang time” for the grapes on vine
What happens regarding the vines in the autumn and winter months following the harvest?
The vines lose their leaves and enter a period of dormancy and fertilizer may be applied in the autumn.
Vines are pruned in the winter months to prepare for the next year’s growth.
What is the difference between climate and weather? Which is most responsible for vintage variation?
Climate encompasses expected temperature, rainfall, sunshine, wind, and other atmospheric elements, and remains relatively stable from year to year
Weather is the daily manifestation of climate, and is generally responsible for vintage variation
What is the range of average mean temperatures annually that the vine prefers? What is the most ideal temperature?
To successfully ripen, what mean summer temperature do red grapes require? White grapes?
50-68F; the most ideal temperature is 57F
Red Grapes require a mean summer temperature of approximately 70F
White Grapes require a mean summer temperature of approximately 66F
Due to temperature requirements, viticulture is generally restricted to between what two latitudes in both hemispheres?
30-50th parallels
What does the California Heat Summation Index do? How many regional categories are there for this?
Classifies climates solely by temperature and therefore recommends varieties appropriate to that temperature
There are 6 categories: Ia, Ib, II, III, IV, V
The California Heat Summation Index classifies climates in 6 categories (Ia-V) based on the number of degree days the climate experiences? How are degree days calculated?
What are the degree days ranges for each category?
Degree days are calculated by multiplying the days in each month of the growing season (defined as April 1-October 31) by the mean number of degrees over 50F for that month. The months’ totals are then added together to arrive at the heat summation category.
Region Ia: 1,500-2,000 degree days Region Ib: 2,000-2,500 degree days Region II: 2,500-3,000 degree days Region III: 3,000-3,500 degree days Region IV: 3,500-4,000 degree days Region V: 4,000-4,900 degree days
Calculate this AVA’s California Heat Summation Index region:
Average Mean Temperatures: April: 58 F May: 62F June: 68F July: 80F August: 79F September: 76F October: 70F
April: 30 x 8=240 May: 31 x 12=372 June: 30 x 18=540 July: 31 x 30= 930 August: 31 x 29= 899 September: 30x 26=780 October: 31x20=620
Total: 240+372+540+930+899+780+620= 4,381
Region V as it is between the range of 4,000-4,900 degree days
What does sunshine contribute to a vine?
Contributes light and heat; enables a plant to photosynthesize, in which the plant converts carbon dioxide into organic compounds, including sugars
What is the minimum amount of sunshine required to support viticulture?
1300 hours
Which climates generally receive more sunshine during the growing season, warmer or cooler?
Cooler climates receive more sunshine during the growing season as the amount of sunshine increases as you move away from the equator
Will cloud cover effect the transmission of light to a vine? What does it inhibit?
Won’t affect transmission of light for photosynthesis but will affect the amount of heat the vine receives
What amount of rainfall annually does a vine require in order to produce an adequate crop? What does this depend on?
20-30 inches annually depending on the warmth of the climate
What is the most ideal climate for quality winemaking vines? Why?
Mediterranean
Receives an abundance of rain but in the winter and spring while remaining dry throughout the summer
What are the benefits of less rainfall? What are the downfalls?
Less rainfall will promote smaller berry size and naturally reduce yields but will interrupt ripening and will lead to complete shutdown of the vine if the water stress is too severe.
What can excessive rain lead to regarding the quality of fruit and disease pressure?
Creates higher fungal disease pressure and dilutes the fruit quality
How can wind adversely affect the vine? What benefits can it provide to the vine?
Can undermine flowering and denude the vine.
In cool climates can deliver devastating wind chills
The benefit it contributes is it can be a detriment to mold and mildew and can even mix warmer air from above with cooler air below to mitigate the threat of frost with the use of windmills
What are the three types of climate a vine is subjected to? What does each refer to?
Macroclimate:
Refers to the regional climate; a larger area that shares a similar climate. For example the Napa Valley floor, the Médoc, a south facing slope of the Rheingau. Broad assertions about a region’s suitability for viticulture can be drawn from the Macroclimate
Mesoclimate:
Refers to the climate of a particular vineyard. The aspect and shelter of a vineyard are essential to distinctions in mesoclimate. Large appellations like Corton may have several mesoclimates within the one macroclimate
Microclimate:
refers to the space in an around the canopy and the space on the vine above ground
What viticulture techniques affect a vine’s microclimate?
Techniques of canopy management such as winter pruning, leaf removal, shoot positioning, and the use of sophisticated trellising systems.
What 4 properties make up the most ideal soil type for vines?
well-draining
easily penetrable
good water retention
heat-retaining (and reflecting) depending on the climate
Higher or lower soil pH contributes to lower pH in wine grapes and thus higher acidity in the resulting wines? Name a great example of soil type that lends high acidity to grape vines.
High soil pH contributes to low pH in grape vines
Limestone is a great example of this soil type.
What treatment can be applied to low pH soils to raise the pH?
Lime
What attributes are considered generally when selecting a particular grape clone?
disease resistance hardiness yield aromatics structure color
What is the difference between clonal selection and mass selection (selection massale)?
Clonal selections are identical reproductions of a single vine.
Selection massale involves the selection of budwood for replanting from a number of vines throughout the vineyard, rather than a single clone.
What is aim of mass selection? What is the result?
To reinforce positive traits and eliminate negative traits through appropriate selection.
The results may be less precise than those gained through clonal selection but genetic diversity is maintained
What species of American vine’s rootstock was the major contributor to phylloxera resistance?
Vitis riparia
What attributes are considered when selecting a rootstock?
resistance to phylloxera
ability to withstand other diseases and drought
tolerance to salt and lime
its effect on vine vigor
At what age does a vine begin to produce a crop of grapes suitable for harvest? By what age is a grape vine considered mature? What stabilizes then?
Starts at age 3; many European appellations prohibit growers from harvesting grapes for wine until the vine is at least 3 years.
Grapevines are considered mature by age 6. Shoot growth and the vine’s annual yield, in the absence of major stresses, stabilize
At what age does a grape vine’s root system become mature?
By age 10
At what age will the grape vine’s yield begin to decline? At what age is it uneconomical to maintain a grape vine?
After 20 years yield declines; after 50 years it becomes uneconomical though exceptions exist as the naturally low yields can produce incredible concentration in grapes such as old-vine Zinfandel and Rhône varieties
What is the main objective of vine training?
To maximize the vine’s performance in local conditions and to keep its canes from touching the ground and establishing new roots.
What are the two methods of vine training? How do they differ at the basic level? Which requires a trellising system?
Head training and cordon training
In cordon training, the vine has at least one permanent cane that extends from the trunk, called an arm or cordon. it grows thick and gnarled over time, and fruit-bearing shoots will emerge from it each season.
Head-trained vines have no permanent cordon, and the trunk ends in a knob or head.
Cordon-trained vines require a trellising system. Head-trained vines rarely require trellising as they’re self-sustaining by nature and don’t need an apparatus such as a tree, stake, or wire trellis to stand upright.
What is an example of a head-training method that requires a trellis?
Guyot
How many spurs does a cane-pruned vine have? How many canes grow during the growing season? How many are retained following the season? What type of vine training uses cane-pruning?
One permanent spur
Two canes grow from the spur, one of which was retained form the previous pruning and contains the buds from which the shoots will emerge.
The newly grown cain will be retained and will be the source of the following year’s clusters. The 2 year old cane will be removed.
Head-trained vines use vine pruning.
What type of vine training system uses spur-pruning only? Which type of training system can be either?
Cordon-trained vines are spur pruned only
Head-trained vines can be cain or spur pruned
What are the two types of vine training? Two types of pruning?
Cordon-training and head training
Cane-Pruning and spur-pruning
What type of training/pruning combo does Guyot employ?
Head-training with cane pruning
What is the simplest form of head trained/spur pruned vine?
Gobelet
What is Gobelet training called in Spain? Italy?
In Spain it is called “en vaso”
In Portugal it is called “albarello”
What do the terms “en vaso” and “albarello” refer to?
They are both synonymous with the Gobelet spur-pruned/head-trained vine system common in the Southern Rhône and Southern Italy
En Vaso is the Spanish term for it
Albarello is the Italian term for it
Cordon de Royat is an example of what training and pruning combo? Where is this system commonly used?
Cordon-trained/spur-pruned
Commonly used in Champagne for Pinot Noir
What are three examples of spur-pruned/cordon-trained vine systems?
Cordon de Royat
Geneva
Lyre
If a vine is trained using the Tendone system, how does it grow? How is it pruned? What is the purpose of this? What is this system called in Italy? What is this system called in Portugal?
Grows upward and overhead along wooden frames or trees. Can be either spur-pruned or cane-pruned.
Trained so that workers to pass underneath. Also promotes good circulation and protection from frost.
Called Pergola in Italy and Enforcado in Portugal
What are the Italian synonyms for Gobelet and Tendone training systems respectively?
Albarello (Gobelet)
Pergola (Tendone)
What are the four main groups of vineyard diseases?
fungal
viral
bacterial
phytoplasma
In what two ways are fungal diseases manifested? What do they attack? How are they spread? What only needs to be infected to spread though the entire vineyard?
mildew or mold
attack either the root system or canopy of the grape vine
fungal spores are spread by wind and rain
only a single vine needs to infected for the fungus to spread through the entire vineyard
What are the two most notable fungal diseases?
powdery and downy mildew
How can fungal diseases be treated?
With fungicide sprays and other applications
How do vines contract viral infection? Are they curable?
Through grading wounds or from insects. They are generally not curable
What happens to vines affected by viruses?
Their life span is shortened
yields are reduced
quality of fruit is changed
If viral diseases can’t be cured, how are they controlled?
Controlled through removal and appropriate selection for propagation.
What kind of disease is also known as “grapevine yellows”?
Phytoplasma disease
Phytoplasmas are similar to what but spread like what?
Similar to bacteria but spread like virus through insect vectors
What is Daktulosphaira vitifoliae?
Phylloxera
What does Phylloxera attack killing the vines in the process?
Attacks the root system of vines
What are three insects that pose disease threats to a vineyard?
mealy bugs
nematodes
glassy-winged sharpshooters
Oidium and Pernospora are known as what two fungal diseases respectively?
Oidium (Powdery Mildew) Downy Mildew (Peronospora)
What is Uncinula necator?
What part of the grapevine does it affect?
What does it look like?
What two things does it greatly inhibit?
How does it affect the vine before flowering and after fruit set?
Oidium/Powdery Mildew)
This fungal disease affects all the green parts of the vine including the grapes, leaves, and shoots.
Looks like a dusty white growth
Greatly inhibits bunch development and ripening
Yields will be reduced if it infects the vine prior to flowering. Berries will struggle to achieve veraison and reach full size if infected following fruit set.
What is Plasmopara viticola better known as? What part of the vine does it affect? What does it inhibit as a result? What does it look like? Can it survive winter? What is used to treat it?
Downy Mildew/Peronospora
This fungal disease affects the leaves of the vine causing them to fall off.
Inhibits vine’s ability to photosynthesize
First symptoms look like an oil spot on leaves. As the spores germinate a white, cottony growth develops on the underside of the leaves.
Can survive on the fallen leaves through winter and can infect the vines again with rain splatter the following season.
Bordeaux mixture, a spray of copper sulfate, water, and lime can prevent outbreaks
What is Bordeaux mixture? What is it used to treat?
a spray of copper sulfate, water, and lime
often used to treat fungal diseases such as Plasmopara viticola (Pernospora/Downy Mildew) and bacterial diseases such as Bacterial Blight
What is Eutypa lata? How does it infect vines? What part of the vine does it affect? How does it affect the yield and quality of crop? What fungus is similar to this?
Etypa Dieback/Dead Arm, a fungal disease common in Mediterranean climates.
Spores are carried by rain and enter the vine through pruning wounds.
Infects the vines at pruning points causing stunted growth as the fungus releases toxins, and eventually an infected cane may die. (dead arm)
Reduces yields but does not affect the quality of crop.
Phomopsis viticola is similar
Which Australian producer is reputable for producing wines affected by Eutypa lata? What is the wine called?
D’Arenberg
Dead Arm Shriaz
What is Esca?
What is responsible for infecting vines with this?
What effect does it have on young vines? Old vines?
How is it spread?
Is it curable?
Also known as Black Measles, a fungal disease
A complex of fungi, rather than a single organism is responsible for this disease.
On young vines it will weaken growth, affect berry development and discolor leaves; in hot weather a young vine may suddenly die.
In older vines the disease affects the wood, causing the interior of the trunk and arms to soften and rot from the inside resulting in spongy soft wood.
Spread by wind or pruning sheers and exacerbated by rain.
There is no known cure for this and vines rarely live past 30 years.
What disease does the Guignardia bidwell fungus create? How did Black Rot spread to Europe? What does the disease look like? What affect does it have on the vine? Is it curable?
Creates Black Rot
This fungal disease spread through the importation of phylloxera resistant rootstock from America.
Looks like a black spot on the vine’s shoots, leaves, and berries.
Reduces yields
Is controlled through fungicide spays
What is Bunch Rot?
What does it do to the vine?
What are two common forms of bunch rot?
a grouping of similar diseases caused by a number of fungi species.
In general, bunch rots reduce crop yields and may adversely affect the character of the wine, imbuing it with moldy off-flavors
Botrytis cinarea is a bunch rot and it can be benevolent (noble rot) or malevolent (grey rot)
What are the following fungal diseases associated with the following fungi?
Guignardi bidwell
Eutypa lata
Plasmopara viticola
Uncinula necator
Guignardi bidwell (Black Rot) Eutypa lata (Eutypa Dieback/Dead Arm) Plasmopara viticola (Peronospora/Downy Mildew) Uncinula nectaror (Oidium/Powdery Mildew
What is caused by the bacteria Xylella fastidiosa?
How is it most commonly transmitted?
How does it impact the vine?
Is there or a cure or control?
Pierce’s Disease
Most commonly transmitted by the glassy-winged sharpshooter, a leaf-hopping inspect found near citrus orchards and oleander plants.
Renders vines incapable of producing chlorophyll and killing it within 1-5 years.
There is no cure or control for this disease
What does bacterial disease the bacteria Agrobacterium tumefaciens cause?
How does it infect the vine?
How does it impact the vine?
How is the disease spread?
Causes Crown Gall (Black Knot)
Infects the vine during winter freezes when the trunk may be ruptured and split open allowing the bacteria to invade the outer trunk.
Creates tumors on the vine or galls that strangle it, withering it or killing outright the portions of the vine above.
The disease is spread through the propagation of bacteria-infected budwood.
What bacterial disease does the Xanthomonas ampelina bacterium cause?
How does this affect the vine?
Is it treatable?
Bacterial Blight is caused by this.
Causes young vine shoots to die
Can be treated with hot water and copper sprays, such as Bordeaux mixture.
What are the corresponding diseases caused by the following bacteria?
Xylella fastidiosa
Agrobacterium tumefaciens
Xanthomonas ampelina
Xylella fastidiosa (Pierce's Disease) Agrobacterium tumefaciens (Crown Gall/Black Knot) Xanthomonas ampelina (Bacterial Blight)
What are the two main viruses a vine may contract? Which is responsible for 60% of the grape world’s production losses?
Leafroll Virus (responsible for 60% of the grape world’s production losses) and Fanleaf Degeneration
Radiant shades of red and gold in autumn on vines indicate the presence of what? What else indicates the presence of this?
Leafroll virus
Downward curling leaves
How does Leafroll Virus affect a vine?
What insect is the most common vector of this?
Will this kill the vine?
deuces yields and delays ripening
Mealy bug is the most common insect vector
It will not kill the vine
What virus is spread by nematodes feeding on roots?
What classification of virus is it considered?
How does the virus affect the vine?
Is this curable?
What symptoms does a vine display?
Fanleaf Degeneration
nepovirus
deforms shoot growth, and leads to poor fruit sed and shot (seedless) berries. Productive lifespan is diminished and the vine’s durability during winter is diminished.
Is not curable and affected vines must be removed
Symptoms include malformed leafs resembling fans in shape.
Where did Flavescence Dorée first appear in 1949? How is it spread? How does it affect the vine? What are the visible symptoms? Is there a cure?
Armagnac
Spread by leafhopper insects and propagation of infected vines
initially delay bud break and slow shoot growth, eventually causing bunches to fall of the vine and berries to shrivel
The phytoplasmic disease will discolor leaves, cause pustules and cracks to form, and may kill young vines.
No cure exists
What is the ideal of sustainable viticulture?
To return the vineyard to a self-sustaining position in harmony with the larger ecosystem to which it belongs.
What does a bottle of American or Australian wine labeled organic indicate?
it is produced from organically-grown grapes, meaning that synthetic chemical treatments and certain filtration procedures are forbidden, although copper and sulfur treatments, such as Bordeaux Mixture, may still be allowed.
Additionally it contains no added sulfites.
If an American or Australian wine is produced from organic grapes but sulfites are added prior to bottling, what will the label read?
Wine made from organically grown grapes
What aspects of viticulture does sustainability govern?
Governs but is not limited to the following:
water usage energy efficiency pest and erosion control the planting of cover crops the degree of mechanization planting decisions labor practices
Integrated Pest Management (IPM) is considered a sustainable approach to what kind of vineyard problems? What is tolerated that isn’t in organic farming?
Approach to weed, insect, and disease problems
tolerates the targeted application of some synthetic products, but limits their use overall.
Producers from what state may belong to VINEA?
What does this organization promote?
What organization’s standards do they farm by?
What are vineyards of member’s belonging to this organization certified as?
Washington
Promotes a holistic, socially-, environmentally-responsible methodology
Farm according to the standard set forth by LIVE (Low Input Viticulture and Enology)
Vineyards are certified as Salmon-Safe
What does OSCW stand for?
What requirements must be met by producers to receive this designation?
Which two organizations can certify wineries for this designation?
What two things must both be certified for the designation?
Oregon Sustainable Certified Wine
97% of the fruit used is Salmon-Safe
LIVE and/or USDA Organic have to certify that both the fruit and winery meet the necessary standards.
What does CCSW stand for?
What kind of certification does this organization provide?
California Certified Sustainable Winegrowing
Provides incremental certification for wineries and vineyards based on a concept of continual improvement.
Who introduced the principles of biodynamic farming in 1924?
What is the winemaker that has led the charge for this style of farming in the Loire Valley?
Rudolf Steiner introduced these principles
Nicolas Joly personifies the farming practices
Which organization certifies biodynamic farms and vineyards internationally?
The Demeter Biodynamic Trade Association more often called simply Demeter
Why is SO2 generally added to fermenting must or juice beforehand?
To prevent oxidation and bacterial contamination and to ensure rapid fermentation.
What is acetaldehyde regarded as a sign of?
oxidation
How is volatile acidity (ethyl acetate) created in wine?
small amounts of acetaldehyde present naturally in finished wine is converted to acetic acid, which in turn reacts with alcohol to produce ethyl acetate
What happens when excessive volatile acidity in the wine has led to the wine becoming faulty?
excessive acetic acid has been produced by the activity of acetobacter, the group of bacteria responsible for turning wine to vinegar in the presence of oxygen.
What happens when the amount of nitrogen present in the fermenting must is defficient?
Because yeast require nitrogen to work, low levels of nitrogen in the must leads to the formation of hydrogen sulfide (H2S), a highly volatile compound reminiscent of rotten eggs.
What compounds are produced under reductive conditions in a fermenting must?
sulfides including H2S, mercaptans and other foul-smelling compounds
What does the amount of heat generated by fermentation depend on? With what does it increase?
Depends on the size of the must and it will increase with increasing must sizes.
What rate and temperature of fermentation do smaller vessels provoke? Large vessels?
Small vessels promote longer cooler fermentations whereas large vessels promote shorter warmer fermentations
Below what temperature will most yeasts cease to act? Above what temperature will most die?
Below 50F most yeasts will cease to work
Above 113F yeasts will die.
Why are white wine fermentations usually done at cooler temperatures? Why are red wine fermentations usually warmer?
White wines are usually fermented at cooler temperatures to preserve fruit and freshness.
Red wines are fermented at warmer temperatures to promote more extraction of color, tannin, and flavor compounds.
What is the risk of a fermentation running too hot?
volatilized (lost) flavor compounds and stuck fermentations
What is bâtonnage? What does it contribute?
lees stirring which adds further complexity and richness
What is the purpose of chaptalization?
to increase the final alcohol and glycerin content of the wine
How does reverse osmosis work in alcohol manipulation of wine?
wine is separated into two constituent parts, the permeate (contains water and alcohol) and the retentate (contains the wine’s aromatic compounds)
The permeate is distilled and then recombined with the retentate at a lower percentage of alcohol
In what year were de-alcholization processes by physical separation made legal in the EU? What’s the stipulation?
2009
Legal as long as the alcohol is not adjusted by more than 2%
What are the two most common agents used for acidification of grape must? Which is preferred and when is it added?
Malic acid and tartaric acid
Tartaric acid added prior to fermentation is preferred
What is malo short for? What happens during this? What does it contribute to a finished wine?
Malolactic fermentation
Lactic acid bacteria convert harsh malic acids into softer lactic acids and CO2.
Rounds out a wine’s texture
What process gives a wine buttery aromas? What is the compound responsible for this?
Malolactic fermentation
Diacetyl
How does Carbonic Maceration work? What must occur to finish the wine?
Whole, uncrushed grapes in an anaerobic environment (under a protective blanket of CO2) initiate intracellular fermentation.
Attempting to sustain itself, a berry will release enzymes to transform its own sugar into ethanol and CO2. This occurs without the action of yeasts. However such fermentations cannot produce more than a couple of degrees of alcohol, as the berry ceases activity in the presence of enough ethanol.
As a result, once carbonic maceration has completed, a standard fermentation will ensue to create the finished wine.
If whole berries are used in the fermentation, what will occur? What grapes is this method commonly used on?
Will cause partial carbonic maceration.
Pinot Noir and Syrah are common grapes that are fermented in this manner
What does whole-cluster fermentation promote?
Better movement of juice and air through the cap.
What do the stems contribute if allowed to ferment with the must?
Contribute spicy aromatic complexity and structure if ripe, but undesirable green flavors in the wine if unripe or damaged.
What are “jacks”?
leftover pieces of grape stem following destemming
What does cold soak aim to achieve? How is it promoted? How long does it typically last? Where was it pioneered and when? What is the most common grape to employ this technique on?
Aims to achieve the extraction of color and tannin prior to fermentation.
It is promoted by allowing must treated with SO2 to macerate under temperatures too cold for yeast to start fermenting, but not cold enough to prevent extraction of color and tannin.
Typically lasts for nearly a week before fermentation
Pioneered in Burgundy in the 1970s
Pinot Noir is the most common grape that this technique is used on.
What is the purpose of letting some juice run off prior to fermentation?
To have a greater ratio of skin to juice, and therefore achieve more extraction.
What does a winemaker hope to extract from the grape skins?
tannin, anthocyanins (color compounds), and flavor compounds with the help of heat and alcohol
What is a chapeau? Pomace?
Chapeau refers to the cap of grape solids (pomace) that develops on the surface of fermenting must in a fermentation containing grape skins.
If the chapeau is not managed what will happen? How is managed?
It will dry out, solidify and prevent extraction.
Managed by submerging and breaking up the cap.
What is pigeage? How is it performed?
Pigeage is a method of submerging and breaking up the cap. Also referred to as punching down.
Performed manually by workers using poles, paddles, or even their own feet.
Also performed mechanically.
What is remontage?
What is it an alternative to?
Which method is best for agitating and aerating the wine must?
How often is each employed?
Also known as pump over. It is a cap management technique alternative to pigeage wherein the fermenting wine is pumped over the top of the cap.
Remontage is better for agitating and aerating the wine must
Can be employed once or several times daily during fermentation
What is délestage?
Cap management technique where the entire fermentation vessel is drained by racking the wine into a separate vessel while the cap drains fully.
The wine is then pumped back over the cap in the fermentation vessel
What are the three most common methods for cap management?
pigeage (punch down)
remontage (pump over)
délestage (drain and pump)
When does maceration occur-before, during, or after fermentation?
Can occur at each period.
Cold soak maceration (pre fermentation)
Normal maceration (during)
post-fermentation for tannic styles like Nebbiolo which can last up to a month following the end of fermentation.
What is the difference between vin de goutte and vin de presse? What wines are each used for?
vin de goutte is the free run drawn off following fermentation and any post fermentation maceration. This wine is the highest quality and most elegant
vin de presse is the wine acquired from pressing the pomace once the free run has been drawn off. This wine is coarser and more tannic.
The vin de goutte (free run) is reserved for top cuvées or wines.
The vin de presse may be blended into a top cuvée for structure, or it may be reserved for lesser wines
What aging vessel is most common for the aging of high quality red wines?
oak barrels-the size and percentage of new barrels is determined by the style of the wine.
For how long do high quality red wines typically age in oak?
Typically age from a few months to more than two years
What does soutirage refer to? What does it provide for the wine?
soutirage refers to the racking or movement of wine from one vessel to another, providing aeration and clarification as the wine is removed from its lees, or sediment.
When does malolactic fermentation occur?
Quickly at the end of a finishing fermentation or slowly during maturation
At what two stages of production is SO2 added following fermentation?
during maturation (élevage) or added just before bottling
What does sans soufre mean?
Without sulfur
What is the main aim of filtration?
To clarify and stabilize the wine prior to bottling.
What is collage?
Fining
What are 5 agents commonly used for collage (fining)?
bentonite casein (a milk protein) isinglass (material obtained from sturgeon bladders) gelatin egg white
What fining agents would create a dilemma for vegan and vegetarians? What is the best agent to use?
casein, isinglass, gelatin, and egg whites would create dilemma
bentonite is the preferred fining agent
What advantage does whole cluster pressing afford to white wine production?
provides good drainage channels for the juice during pressing
For how long will white wine grapes remain in contact with their skins following crushing and prior to pressing? What’s the disadvantage of this? Advantage?
hardly any time at all as excessive tannin and bitterness can be extracted if maceration is too long. if done properly, extra aromatic compounds can be extracted.
If it does occur it will only occur for a few hours.
What is débourbage?
What does it allow and promote?
During this stage, what are the two biggest enemies to the pressed juice? How are these threats mitigated?
The process of allowing the unfermented juice to settle following pressing
allows the juice to be racked off suspended solids and clarified prior to fermentation
The two biggest enemies during this stage are heat and oxygen. These are mitigated by keeping the must cool and the addition of SO2
What does cold stabilization aim to do?
Aims to cause tartrate crystals to precipitate out of the wine at a temperature of 25F.
If crystals form in a bottle of white wine, what process must have been avoided prior to bottling?
cold stabilization
Following the fermentation to dryness of lighter high acid wines, what may be added to balance out the tartness? Where is this common? What is the name of the agent added for this purpose there?
Sugar in the form of unfermented grape must is sometimes added if the fermentation wasn’t arrested.
This is common in Germany where the grape juice is called Süssreserve
What style of white wines are often filtered-dry or off-dry/sweet? Why?
off-dry and sweet wines as they contain fermentable sugar filtration is necessary to remove any yeast that may metabolize this residual sugar.
What are two reasons a white wine following fermentation will be allowed to stay in contact with the lees?
To encourage malolactic fermentation as malolactic bacteria feed on the nutrients contained in the lees.
Supplement richness and body in the wines through bâtonnage
For how long do barrel aged quality white wines remain in barrel prior to bottling?
Between 9-18 months
What are the two basic methods for rosé wine making? Which is widely prohibited throughout the EU? What are the exceptions to this?
Blending of base wines and limited skin maceration.
Blending of base wines is widely prohibited it, but allowed for the production of Champagne
Below what level is blending of base wines allowed for the production of rosé in the EU?
Below the PGI level
What is the difference between saignée and vin gris?
Saignée is the bleeding of juice from a fermentation vessel for the benefit of red wine production. Rosé is the byproduct.
Vin Gris is the production of a rosé (or more accurately, a white wine from red grapes) by direct pressing of whole cluster grapes which give the wine a slight hue. Commonly produced from the Pinot Noir.
What does aging in oak do for a wine?
Allows gentle, slow oxidation to occur, rounding out and softening the textures of wine.
After how many years of using an oak vessel does it become neutral?
after 4-6 years
What is microbullage?
an aeration technique in which small amounts of oxygen are allowed to enter a stainless steel tank during either fermentation or maturation of the wine
The combination of what two techniques can be used to simulate the effects of new oak barrels on wine in a neutral vessel?
The use of oak chips and microbullage can simulate using new barrel at a fraction of the cost
What are the two most common species of French oak used?
What is the main American oak species?
How does French oak differ in structure compared to American oak?
Why does American oak lend more vanilla and coconut aromas to wine than French?
Quercus robur and Quercus petraea are French
Quercus alba is American
French oak has a tighter grain as a result of its slower growth whereas American oak has a wider grain.
American oak is less porous than French and can be sawn rather than hand split without fear of producing staves that are leak prone. As a result of the sawing more vanillin and lactones leach out of the staves and into the wine. Additionally, American oak is quickly dried in a kiln which concentrates the lactones whereas French oak is air dried allowing the lactones to be leached out prior to use for aging wine.
What are the terms for warming, shaping, and toasting oak staves respectively?
chauffage (warming)
cintrage (shaping)
bousinage (toasting)
What level of toasting will promote the most extraction of wood tannin? Lactones? Which level will result in the subsiding of lactone levels and instead contribute spicier, smokier aromas?
Light toasting will promote the most extraction of wood tannin.
Medium toasting will extract the most lactones
Heavy toasting will promote spicier, smokier aromas
What is the difference between coulure and millerandage?
Coulure refers to unfertilized embryo so no grape
Millerandage refers to poor fertilization resulting in hen and chicken so berries but of varying sizes
