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Wednesday, October 1, 2008

Why does my wine contain milk products?

This unusual question was posed recently by a customer who was rather surprised to find the following label on the back of her Chardonnay - 'This wine has been produced with aid of milk products and traces may remain' thus leading to the perplexing question of what milk was doing in a bottle of wine.

For the answer to this we can look back to 2002, when the Food Standards Authority (FSANZ) revised the food standard for Australia and New Zealand. Within this revision, wine was more formally recognised as a food, thus subjecting wine to the same (world class) standards of health and safety as 'food products'.

Also in the revision was a change in food labelling, including the advent of the allergen warning - a declaration requiring producers to specify if certain substances have been used as an ingredient, food additive or processing aid and are present in the final product. These substances have been identified as allergens - substances that can cause an adverse allergic reaction in humans. They include:

- Cereals containing gluten and their products
- Crustacea and their products
- Egg and egg products
- Fish and fish products
- Milk and milk products
- Nuts and sesame seeds and their products
- Peanuts and soybeans, and their products
- Added sulphites in concentrations of 10mg/kg or more
- Royal jelly
- Bee pollen
- Propolis

Now wine is a classically natural product (fermented grape juice) with stringent laws on what can be 'added' to wine, yet there are some quite unusual natural products that are used in the production process. Previously, little attention was paid to these products, however the increased awareness of allergens and the increased prevalence of allergies ultimately spurred the food standards authority to introduce the requirement for the allergen warning.

Some products used by winemakers include several foods (listed above) which are recognised as common allergens, including milk, eggs and fish, all of which are used as fining and clarifying agents (leading to brighter, cleaner wines). Egg whites, for example, are sometimes added to red wines to remove astringent tannins. The protein in the egg whites bind to the tannins, which then polymerise and form a deposit in the bottom of the barrel. Before bottling, the wine undergoes a process of racking, whereby the wine is seperated from the solid sediments, leaving the egg white deposit behind in the barrel (thus little, if any, actual egg white actually makes it way into the final wine - particularly after the wine passes through standard filtration).

Some of the other substances used by winemakers include casein, a protein derived from milk (which is used for clarification), or Isinglass, which is derived from fish swim bladders. Some winemakers also add tannin to red wine to give it more 'body' and the tannin can occasionally be derived from chestnuts.

The reality is that most of these products are used largely as production aids and the additions are so minimal, with such low concentration in the final product, that they are viewed as essentially innocuous. A study funded by the Australian government wine & grape research body (GWRDC) found that negligible levels of allergens remain in finished wines, and as yet there has been no medical evidence to support any linkage between wine fined with egg, fish or milk products and allergic reactions.

So next time you spot a wine 'produced with the aid of fish products' think allergies and not seafood
Andrew Graham


  1. This unusual question was posed recently by a customer who was rather surprised to find the following label on the back of her Chardonnay. Bordeaux wine

  2. oh em gee! I'm lactose intolerant and a lover of wine, this is NOT good news! Thanks for sharing.

    1. If you are lactose intolerant then you do not need to worry about the addition of casein to wine. Lactose is the sugar found in milk whereas casein is one of the proteins. People with cows milk protein allergy or intolerance can digest lactose without problems and people with lactose intolerance can digest milk proteins without problems.
      As a blogger on this subject you might want to find out a bit more about the difference between the two for benefit of your readers, as well as yourself. Well done on the product reviews though, I might be buying some Tesco doughnuts later this week :)

    2. Currently got a fat face and restricted breathing, curtesy of a pinot grigio. Just discovered it had milk in it! Not impressed.

  3. i would like to no how long will the cheap wine last with this crap egg and milk in its makeing after opening it

    1. You are everything that is wrong with the internet.

  4. Can't spell either

  5. i am a vegetarian and I recently bought a classy wine just to realise that it had mentioned".....milk and fish products and traces may remain"... I chucked the wine in the glass which i had poured.. fish or fish remains or anything related to the "flesh" is definitely not vegetarian.. what do I do?

    1. The amount of animal protein used in wine is equivalent to the occasional bug in your greens.

    2. Buy wine from Coop who clearly label VEGAN wine

  6. Time for cop on, too much information poorly misunderstood. 1% Of the population are coelics, however in our bistro which seats 28 people, one night we had 14 people who said they needed a gluten free meal because of allergys, BS

  7. There are plant-based fining and clarifying agents that sadly most wineries choose not to use. Oxford Landing's entire line of wine is vegan, as is Yalumba's (except for their tawny and muscat). You can check for a wine's veganosity here:
    - @donnzpg

  8. "cheap wine, crap egg and milk" I love it! Me box of goon has gone rotten! F'oaff whadi do?