Tartrate Stabilisation

Question 1

Does tartrate stabilisation take place before or after fining

Answer 1

After. It’s very important to carry it out afterwards as the colloids protect the tartrate , keeping it soluble. So if the colloids are still present in the wine during the tartrate stabilisation it won’t be as effective.

Question 2

Name 5 forms of tartrate stabilisation

Answer 2

Cold stabilisation
Contact process 
Ion exchange
Electrodialysis 
Metatartaric acid
Carboxymethylcellulose (cellulose gum)
Mannoproteins

Question 3

What are the issues with cold stabilisation, and what is the process that was developed as a direct solution to it?

Answer 3

• slow (up to 8 days)
  Lord of energy required to chill and maintain the temperature at-4C.
  If there are any colloids in the wine (of the fining hasn’t been as thorough as possible) the crystals won’t precipitate out.

The process created as a solution to this expensive and imperfect method was the contact process

Question 4

How does the contact process work?

Answer 4

It speeds up the cold stabilisation process and enables it; wine is chilled to 0C (as opposed to-4 or -12 for fortified wines) and potassium bitartrate crystals are added and kept in suspension to maximise the exposure to the wine. This happens for2 hours (vs 8 days of cold stabilisation). The tartrate in the wine bind to the potassium bitartrate nuclei and are filtered out while the wind is still cold.

Question 5

What is a key difference between the contact process and cold stabilisation methods, and ion exchange?

Answer 5

The ion exchange prevents crystallisation, while the other two remove excess tartrates.

Question 6

Pros and cons of electrodialysis

Answer 6

Pros:
It’s reliable
Can be tailored to specific wines
Low energy costs once it’s running

Cons
Expensive initial cost

Question 7

What style of wine is suitable for stabilisation using metatartaric acid?

Answer 7

Given it is ineffective after 18 months and, after that point, can cause increased tartrate levels as the compound breaks down, it is only really suitable for wines designed to be drunk young.

It is also used by small wineries that can’t afford the equipment and cost of cold stabilisation or contact process.

Question 8

What is the maximum dose of metatartaric acid allowed?

Answer 8

100mg/L

Question 9

How does carboxymethylcellulose work as a stabiliser?

Answer 9

Like metatartaric acid, it coats the potential sites of crystalisation in the solution thus stopping crystals forming.
The benefit of it is the effects last longer than metatartaric acid.

Question 10

Which has the higher legal limit- carboxymethylcellulose or metatartaric acid?

Answer 10

Both are the same at 100mg/L

Question 11

Mannoproteins were devised as a method of tartrate stabilisation after studying wines that have undergone what process?

Answer 11

Maturing in the lees. The mannoproteins were released by the yeast, and produced a stable colloid that interferes with the production of the crystals.

Question 12

How long are mannoproteins effective?

Answer 12

Longer than metatartaric acid and carboxymethylcellulose because the colloids are stable