Wine Making Option

Question 1

What is sedimentation

Answer 1

• Clarification method
• wine allowed to stand, particles with higher density than wine form a sediment at the bottom
• wine racked off
• number of racking depends on size of container
• only clarification allowed for some premium wine -> preserve flavourful and texture
• takes time -> costly

Question 2

What is centrifugation

Answer 2

• clarification method
• spins the wine at high speed
• expensive machine -> high volume production to spread the cost

Question 3

What is filtration

Answer 3

• most common way of clarification
• wine goes through filter system of porous layers that trap solid particles

Question 4

What is fining

Answer 4

A procedure in which a fining agent is added to speed up the precipitation of suspended material in wine
- fining agent and colloid (insoluble particles) have opposite charges, attract each other and form solid large enough to be removed
-> clarify wine
-> stablise wine against formation of haze in bottle
-> removal hash tannins or browning

Question 5

Common types of fining agent

Answer 5

• remove unstable proteins
• remove phenolics that contribute undesirable colour and bitterness
• remove colour and off-odours

Question 6

Why fining agent to remove unstable protein

Answer 6

• proteins in white and rose wines would gather to form visible haze -> fault

Question 7

What is bentonite

Answer 7

Fining agent in a form of clay that absorbs unstable proteins and unstable colloidal matter
-> lost of colour and large sediment

Question 8

Fining agent to remove undesirable color and bitterness

Answer 8

• egg white (allergen, must be declared)
• gelatine (protein extracted from pork)
• casein (milk derived protein, allergen)
• isinglass (fish bladder derived protein collegen)
• vegetable protein (potato or legumes)
• PVPP ( insoluble plastic, used in white wine)

Question 9

Fining agent to remove colour and off odour

Answer 9

Charcoal
- over fines easily -> remove aromas and flavourful
- may use in small batch and blend with the rest

Question 10

What is the role of blending

Answer 10

• create a balanced wine: increase or moderate certain characteristics (e.g. Merlot (body and ripe fruit) with Cab S with a stringently tannic)
• consistency across vintages
• desired “house style”, or premium style for aging or mid price style for early consumption
• increase complexity
• minimize fault (e.g. wine with VA sterile filtered and blended into larger volume)
• volume: blending with wine from cheaper grapes to keep price down (e.g. Chardonnay with Trebbiano and Semillon)

Question 11

When not to blend wine

Answer 11

• produce “single vineyard” wine to maintain character of the fruit/ quality from that vineyard
• preserve distinctive aromas (Sauvignon Blanc, Riesling)
• legislation

Question 12

What is blending

Answer 12

Mixing together two or more batches of wine, usually before finishing and packaging
- grape varieties
- locations
- Grape growers / business
- vintages
- treatment (free run and press, oak and unoak)
- small vessels to make up required volume