Mature, Treat & Bottle Flashcards
What is the ‘last resort’ fining agent to remove off-odours and colour?
Carbon
What is HPLC?
High performance liquid chromatography
Which country imposes limits for Sorbic Acid?
Japan
What is 2,4,6 Trichloroanisole? What is it responsible for?
TCA a Haloanisole largely responsible for cork taint
What is Quercus Robur?
A European Oak Low in odiferous compounds but high extractable polyphenol content
Name three reasons you might use Reverse Osmosis for grape musts or finished wine
-Concentrate grape musts by removing water -De-alcoholism a finished wine (EU max reduction 2%) -Decrease high levels of acetic acid
What fining agent is often used in ‘fine’ wines to remove harsh, green tannins?
Egg albumen
What size to oak chips come in?
6.35mm~2cm
What type is a cork made from natural cork coated with a mixture of cork dust and latex?
A Colmated cork
Other than from corks where else can Cork Taint come from?
Barrels Pallets Plastics Winery eqpt Bentonite
What are you trying to reduce if you were to use Potassium Ferrocyanide for white wine Or Calcium Phytate for red wines?
Excess Iron
Which type of Filter can be washed and reverse flushed to remove blocking particles?
Membrane Filters
Which wood drying process will impart the least tannic effect on the wine; Air dried or Kiln dried?
Air dried
Due to the amount of lees that can precipitate using Bentonite how much wine loss can there be?
10%
What is Quercus Patraea, formally known as Quercus Sessiliflora? What flavours does it bring?
European white oak Eugenol (cloves), Vanillin (oaky and vanilla)
What is the Filterability Index and what 2 main things make it up?
The clogging power of a wine - % of solids - Size of particles and their nature
Bottling using heat Which process uses medium temperature for a long time? What temperature? What is the main advantage?
Thermotic bottling About 55c No need for sterile bottling as product rendered stable during heating process
Which fining agent is Silica Sol often combined with and why?
Gelatin or Isinglass to help floculation
What is the name given to red wine maturation which reduces herbaceous aromas, provides better structured wins, better oak integration, better controlled reductive characters and speeds up the maturation process?
Micro-oxygenation
What is a Vinolok?
Glass or plastic closure developed in Germany
What is the main potential disadvantage of Flash Pasteurisation?
Potential re-infection at the bottling machine
What type of filter can handle even the dirtiest of wines without getting clogged?
A Cross Flow Membrane Filter
During maturation what level of free SO2 should there be?
> 20mg/L
A white wine has colour and oxidative taints, what fining agent would you use?
Casein
What is Montmorillonite Clay better better known as?
Bentonite
In wines with low acidity and low SO2 what can Lactic bacteria result in?
A slimy and ‘ropey’ texture
What free level of SO2 will usually prevent the growth of microorganisms in wine?
20mg/L free
In Filtration ‘Absolutely Rated Surfaces’ are rated according to their what?
Maximum pore size
Toasting The lighter the toast the more …………….. what? The heavier the toast the more …………… what?
Lighter = more oaky or woody Darker = more spicy and toasty
What is the word when unwanted components in a wine clump together and fall out of suspension
Floculation
What are the 2 ways to carry out ‘asceptic’ bottling?
Filtration Heat treatment
What species of Oak is traditionally associated with Rioja?
Quercus Alba - American Oak
What is ‘The Contact Process’ used for?
Seeding wine with finely powdered Potassium Bitartrate crystals to act as seeds for further growth to remove larger Potassium Tartrate crystals from wine
What is Quercus Suber
The Cork Oak tree
How long is French Oak traditionally seasoned for before being made into barrels?
18~36mo
What would mass-spectrometry combined with solid phase micro-extraction be used for?
QC processes to check for cork taint
In Filtration ‘Nominally Rated Surfaces’ are rated according to their what?
Average pore size
Bottling using heat What process uses high temperature for a medium length of time? What temperature and for how long? What is the main advantage of this process?
Tunnel Pasteurisation >80c for 15 minutes No need for sterile bottling as finished product rendered sterile post pasteurisation
Which fining agent? -Facilitates the stabilisation of new wines by partial precipitation of excess proteins -May also be added to white wines, with Gelatin, to aid the fining process?
Tannin
What is the difference between Quercus Patrea and Quercus Robur?
Both are European oaks with QP being tighter grained than QR. Quercus Patrea is the most highly valued oak
Which red wines are considered most susceptible to Brett?
High pH (lower acidity) new Syrah and Cab Sav
What is a RDVF (Rotary drum vacuum filter) and what is it used for?
A rotating drum, used for Earth Filtration, through which wine is sucked by a vacuum pump.
What chemical is now avoided in cork production Why?
Chlorine Suspected responsible for TCA cork taint
What can be added to wine to ensure no re-fermentation in bottle? What are potential drawbacks of using it?
Sorbic Acid Lactic acid bacteria can metabolise Sorbic acid to produce a smell of Geraniums
What type of filter is used to sterilise wine just before bottling?
Membrane Filters
Bottling using heat Which process uses High temperature for a short period of time? What temperature?
Flash pasteurisation Wine heated to 80~90c
What is the minimum g/L Titratable Acidity for wines sold in the EU?
4.5g/L
What can be 4 objectives of blending wine?
Achieve a certain style Standardisation / consistency Best balance and complexity Blend out faults
What 3 ways can excess Copper be treated?
Bentonite fining Addition of Gum Arabic Blue Fining
What are the 5 main methods of clarification?
Sedimentation and racking Fining Filtration Centrifugation Flotation
What is Fehlings titration used to measure?
Residual sugars
A wine is suffering from bitterness, astringency, harsh tannins (red) and/or off tastes, what would you fine it with?
Gelatin
What type of cork is made from cork granules stuck together with glue?
An Agglomerated cork
What size filter would you use on the bottling line to carry out sterile filtration?
0.45mu
What is the biggest drawback of Cold ‘sterile’ (asceptic) filtration in bottling?
The cost of generating loads of hot water
In white wine what is Isinglass used for and what is one drawback of using it?
To improve colour clarity and vibrancy Forms light, fluffy lees that are prone to block filters
Which Bottling using heat method may positively advance the maturity of a wine?
Thermotic bottling
What fining agent would you use in a white wine to reduce bitterness and browning?
PVPP
What filtration system risks leaving a ‘papery’ taste to wine?
Sheet or pad filtration through Cellulose pads
What are spoilage microbes favourite temperature for growth?
20~35c
What process is described here? “Both the texture of the wine and the flavours change with contact and stirring, producing a softer, richer, more complex wine”
Lees ageing with stirring (bâtonnage)
What is the optimum humid range for wine matured in oak?
75%~80%
What, in wine, are most difficult to remove by sedimentation
Colloids
What are the 3 Haloanisoles responsible for Cork Taint?
TCA TBA TeCA
What might you use a Flame Atomic Absorption Spectrophotometer for?
Trace metal analysis
What type of test is done to test for protein stability?
Heat stability tests
What might you add to wine to prevent Calcium Tartrate crystals forming?
Metatartaric Acid
What is the name of the filtration method than can filter out specific components from a wine e.g. tannins, sugars and acids?
Ultra-Filtration
What is the single biggest disadvantage of switching from using natural corks to screwcaps?
The cost of specialised bottling eqpt and the special bottles required
What is most commonly used to fine for unstable proteins?
Bentonite
What measurement might be used to detect potential fraud in wine? What does it actually measure?
TDE (Total Dry Extract) measurement Measures all non volatile matter in a wine
What is ‘asceptic’ bottling?
The elimination of any potentially harmful yeast and/or bacteria in a wine
What is the main advantage of Surface Filtration?
It is absolute
What is the name of the Cork Oak tree?
Quercus Suber
What is described here? “The addition of an agent or agents to a wine which aid the removal of colloid materials from suspension”
Fining
Bottling using heat Which 2 methods heat sterilise the wine, the bottle and the closure?
Tunnel pasteurisation and Thermotic bottling
What are being described here? “Positively or negatively charged and between 2~1000nm in diameter being too small to be removed by filtration alone”
Colloids
What are ‘Technical corks’?
An Agglomerate cork with natural cork either end Or An Agglomerate closure of which particles have undergone supercritical carbon dioxide technique to remove TCA
What is the major constituent of Volatile Acidity?
Acetic acid
What are the 3 MAIN instability problems a wine can face?
Tartrate instability Oxidation and reduction Microbial spoilage
What is the top and bottom of a barrel called?
The Heads
What is Quercus Alba? What flavours does it bring?
American Oak Oak lactose (coconut)
What might you use Gum Arabic for?
A protective Colloid that prevents tartrate crystals growing large enough to be visible. Effect in wine is 12mo
What is the official EU method for measuring SO2 levels in wine? What level of SO2 is measured?
The aspiration method Total SO2
A white wine is suffering from a protein haze, what would you use as fining agent?
Bentonite or Silica Sol
What process is used to produce high quality grape juice concentrates that might be used to sweeten musts prior to fermentation?
Osmotic distillation
What is the effect of MLF taking place in bottle?
Unpleasant smells, and a clouding of the wine
What is a 44x24?
A cork, 44mm long x 24mm diameter
When using Casein what should it be used in conjunction with and why?
Used with Tannin to achieve precipitation
What pore size would you use to remove all traces of yeast and bacteria from a wine using Surface Filtration?
0.45mu
