Winemaking Flashcards
techniques to stop the AF
- fortification: stop AF while sugar is still present & kills the yeasts
- add a lot of SO2
- chill the fermented wine
crushed fruit fermentation
- extraction and temp control
pre-fermentation extraction: fruit is crushed. some prefer to leave the grapes to macerate at low temp before AF.
to extract colour and glavour.
temperature: 20-32°C
list the cap management techniques
- punching down
- pumping over
- rack and return
- rotary fermenters
- fermentation in large vessels
- post-fermentation extraction
- press wine
how is it called when you dry grapes on the vine
“passerillage” –> full sugar ripeness, grapes dehydrate and turn into raisins
need warm + dry autumns
–> late harvest
name the sweet wines by noble rot and explain the characteristics of the berries and environment
- Sauternes, Tokaji, Beerenauslesen, Trockenbeerenauslesen
- grapes must be fully ripe
- humidity + misty mornings and sunny and dry afternoons
- fungus punctures the grape’s skin –> filaments
flavours: honey, apricot, citrus zest, dried fruit
winemaking choices Pinot Gris and Chardonnay (non-aromatic)
- controlled exposure to oxygen
- clarification via settling/decanting
- MLC encouraged –> rounder and creamier
- usually not blended
Pinot Gris:
- characteristics
- climate
- where
- early budding + early ripening
- warm climates –> high sugar, loses acidity
- Alsace: oily, ripe tropical fruit, ginger and honey
- Trentino Alto Adige and Friuli: high quality, dry style. small berries, great flavour concentration
Chardonnay:
- characteristics
- climate
- where
- early budding + suffers in areas with spring frost
- cool climate: green fruit and citrus
- moderate climate: peach, melon and lemon
- warm climate: stone fruit + tropical, can lose acidity quickly
- Burgundy: Chablis, Cote d’Or, Maconnais
- MLC + extended lees
age –> mushroom + umami
list the techniques to make a sweet wine
- stop AF
- add sweetening component
- concentrate grape sugars
- noble rot
- drying grapes on the vine
- drying grapes after picking
- freezing grapes on the vine
what are the 3 forms of whole bunch fermentation
- carbonic maceration
- semi-carbonic maceration
- whole bunches w/crushed fruit
explain carbonic maceration
uncrushed bunches into vats, fill with CO2 to remove oxygen
- intracellular AF starts
- level of alcohol reaches 2% –> grapes skin splits and grapes release juice
- yeasts complete AF off the skins
- extract colour, little tannin
- wines soft and full of fruit
explain semi-carbonic maceration
- vats filled with whole bunches
- grapes at the bottom of the vat are crushed under the weight of the grapes above –> juice released
- ambient yeasts start to ferment the juice –> CO2 is produced –> carbonic maceration
explain whole bunches with crushed fruit fermentation
fill the vats with whole bunches and crushed grapes at the start of the AF –> cap regularly punched down
winemaking options for high volume inexpensive reds
- warm, sunny, dry environment
- Cab Sauv, Merlot, Syrah, Grenache
- juice handled protectively with SO2 monitored
- grapes destemmed and crushed at arrival
- tartaric acid added –> raise acidity
- AF + commercial yeasts –> 22-25°C
- may macerate a small % + blend
- oak may be used
list varieties for premium reds
- Cab Sauvignon
- Merlot
- Pinot Noir
- Syrah
- Grenache
3 ways of making rosés
- direct pressing: black grapes crushed and pressed –> extract a little colour
- short maceration: extract colour and flavour –> free run juice drained off the skins and fermented at cool temperature
- blend red+white wine
grapes processing at the winery
- grape reception –> 1st dose of SO2
- destemming and crushing –> free run juice
- pressing: whites, before AF; reds, after AF
oxygen in maturation, types of vessels
- inert airtight tanks –> avoid oxygen –> steel, cement, epoxy
- oak –> some oxygenation –> soften tannins and more flavour complexity –> tertiary aromas
oxygen in winemaking, how to avoid it
- avoid it to maintain primary fruit aromas
- SO2 to keep contact to a minimum
- grapes picked at night –> cooler –> less oxygen
- protective/anaerobic winemaking
adjustments before-during-after AF
- sugar and alcohol –> enrichment with RCGM
- remove water from the juice to concentrate sugars
- acid:
- acidification: add powdered tartaric acid
- deacidification: add alkaline substance
what is AF
conversion of sugar into alcohol & CO2 through yeasts.
min temp = 5°C
max temp = 32°C
yeasts in the AF and types of yeasts
- to kill yeasts: add SO2 or grape spirit
- remove via filtration
- ambient yeasts: increase flavour complexity
- cultured yeasts: limit the potential complexity, but ensure expected result
results between low and high temp during AF
low: avoid loss of volatile aromas
high: extract colour and tannin from black grapes
MLC, what is it and how to encourage/avoid
MLC = lactic acid bacteria converts tart malic grape acid into softer lactic acids.
- after AF
- softens + reduces acidity + buttery + produces CO2
- encouraged = raise temp of wine, not add SO2 after AF
- avoided = store at cool temp, use SO2 or filter bacteria
elements needed to survive ageing in pre-bottling maturation
sufficient levels of:
- alcohol
- tannins
- acidity
- interesting flavours that will evolve
main techniques of clarification
- sedimentation/decanting: wine slowly and gently pumped in a different vessel –> racking
- fining: add fining agent –> creates clumps that are removed via filtering
- filtering –> through filter before/after AF
3 areas that require stabilisation + solutions
- tartrate stability: crystals (tartrates) –> cool temp accelerates formation –> remove via filtration
- microbiological stability: yeasts and bacteria. appropriate handling of SO2, sterile filtration before packaging
- oxygen stability: avoid exposition of oxygen and keep SO2 topped up.
cork taint is caused by
TCA = trichloroanisole
producing high volume inexpensive whites (steps)
- SO2 monitored
- grapes (destemmed), crushed, pressed
- before AF clarify juice –> centrifugation
- stainless steel/inert vessel –> AF –> cool temp
- commercial yeasts
- rack off the lees
- stabilisation + fining + filtration
- SO2 levels topped up at bottling
winemaking choices for Riesling and Sauv Blanc (aromatic)
- SO2 levels monitored
- clarification via settling/decanting
- cool AF temp –> primary fruit aromas
- MLC usually avoided –> preserve acidity
- Riesling: lees contact possible for texture + flavours
- creamy & spicy Sauv Blanc –> California & BDX –> barrel fermentation
advantages of fermenting in oak
- transfer heat effectively
- add rich flavours and round texture
what will stop AF
- all sugar in the must is consumed
- yeasts run out of nutrients to metabolize
- temp exceeds 35°C
important considerations WM takes into account after AF for whites
- what vessel to use
- blend?
- lees age?
- allow/block MLC?
- fine or filter and how much?
benefits of blending white wines post AF
- improve consistency, texture and flavour
- enhance balance
- particular style
less costly method than oak barrel
oak staves/chips
what is bâtonnage and its benefits
when a WM stirs the lees that fell to the bottom of the vessel and breaks them so they release amino acids –> creamy, round mouth filling
effects of MLC
- lowers acidity
- creates a little CO2
- melted butter aroma
what white grape varieties are more likely to undergo MLC
Chardonnay and Viognier
what are the 2 sugars found in grapes that are easily converted in alcohol
glucose and fructose
why do WM avoid skin contact for white wines
reduce the risk of oxidation and extraction of unwanted flavours
optimum AF temp for white wine
12-22°C
what does cold soaking do
encourages a slow, long extraction of flavours and colour from reds at cool temp
5 steps in traditional red winemaking
- pre-fermentation processing
- AF
- draining and pressing
- MLC
- maturation
winemaking elements that need to be managed during red winemaking
- density and temp of must
- oxygen level of must
- cap created during AF
- duration of skin contact
typical temp range for red AF
20-32°C
what is the cap
accumulated skins, seeds and other grape solids that float on top of a fermenting red wine
what happens if cap is not managed
wine less tannic, lighter in colour and less flavour
benefits of cap management
- reduce heat accumulated during AF
- allow oxygen in the must and break the cap
why punching down to be done more carefully than other techniques
can result in exceedingly bitter and rough final wine
advantage of the rotary fermenters
fast extraction
what wine region is most well known for both carbonic and semi-carbonic maceration
Beaujolais
what aromas does carbonic maceration give to a wine
banana - kirsch - bubble gum - spice notes
how long does carbonic maceration take
1-3 weeks
do rosés wines undergo MLC
MLC is avoided for rosés to keep the fresh acidity
what temperature is direct press rosé fermented
12-22°C
what wine regions are known for making rosé using direct press method
Côtes de Provence and Languedoc
