What’s Wrong With Wine (and other alcohol)?
YES, even wine!
The safest way to be sure that your wine, beer or spirits contain no animal products is to directly contact the producer or importer. Alternatively, visit the website for Barnivore or The Vegan Connection for lists of Vegan-friendly booze!
It’s the fining process that’s the problem for vegans and vegetarians. The grapes come in and the first round of crushing (called “free run”) gives the best quality wine. However making wine is a business and, after the first crush there is still a lot of wine left amongst the pulp and skins. Unfortunately, amongst the skins and seeds there lurk the phenolics.
Phenolics can cause the wine to have a bitter aftertaste, “off-odour”, discolour the wine and cause it to degrade quickly. In order to retrieve the residual wine the grapes are then pressed. Often, to make the pressed wine palatable, it goes through a fining process which involves the addition of an agent to filter out the bad stuff.
The fining process works:
- by electrical attraction between agents of a given charge attracting oppositely charged suspended substances (s.s.)
- a chemical bond is formed between the s.s. and the fining agent
- the s.s. is absorbed within the structure of the fining agent, or
- the s.s. binds to the surface of the fining agent
- the fining agent then sinks to the bottom of the tank taking most of the s.s. with it
The fining treatment chosen will depend on the wine to be fined, and the particular adverse property to be removed. Another factor which influences choice of fining agent is how much of the good stuff will be compromised by the fining process. Obviously there is an art to fining wines! Most fining acts by attracting oppositely charged particles: for example, gelatin is positively charged and will pull out negatively charged particles in the wine, bentonite is negatively charged, egg whites are positive, silicon dioxide is negative.
Sometimes two agents will be used, such as the positively charged Kieselsol followed by the negatively charged Chitin in a tag team to remove positively charged and then negatively charged substances. It should be noted that just because a wine is vegan one vintage, it will not necessarily be vegan in subsequent vintages.
Commonly used fining agents for wine
Alginate (polysaccharides) – removes yeast cells and tannin
Activated carbon (activated charcoal) – removes “off-odours”, browning and oxidation in white wines (not popular)
Blood (defibrinated ox blood) – reduces tannins
Bentonite (clay) – removes protein
Casein (the major milk protein) – improves clarity in white wine and sherries, and reduces iron and copper content
Chitin or Chitosan (from lobster and crab shells) – clears white wines, and when combined with Kieselsol, removes most suspended proteins and solids
Egg white - reduces the level of astringency and bitterness in red wines, and removes haze caused by excess tannin Egg shell – aids clarification and reduces discoloration in white wines
Gelatin (from animal bone and skin) – reduces astringency and bitterness in red wines
Gum Arabic (natural gum derived from acacia trees) – removes copper and iron, and increases effervescence in sparkling wines
Isinglass (derived from air bladders of fish) – removes tannin, phenols, colour, and yeast
Kaolin (similar to Bentonite clay) – removes protein
Kieselsol (silicon dioxide) – removes bitterness, and is often used in combination with Chitin
Metatartaric Acid (polymerized tartaric acid) – prevents potassium bitartrate dissolved in wine from forming crystals
Pectin destroying enzymes (enzymes extracted from plants)
Polyvinyl-polypyrrolidone (PVPP, a synthesized product) – removes browning and pinking discolouration, bitterness and oxidised flavours
Silica gel (Kieselsol) (silicon dioxide suspension prepared from acidified sodium silicate)
Skim milk - removes bitterness and hardness of white wines and sherries
Spakolloid (made from fossilized skeletons of hard shelled algae) – reputed to create brilliant wine without stripping character.
Yeast- removes protein, copper, sulphate, ethyl acetate, browning, oxidation and excess oak.