Additives in Wine

Additives in Wine

Most of us innocently think of wine as fermented grape juice. There are however many other additives or “ingredients”, these can be split:

  • Animal Products in wine: unfortunately too many wines use these as additives or processing aids.
  • Additives in wine: substances and chemicals added to wine that stay there and become part of the finished product.
  • Processing Aids in Wine: substances used in the process of making wine.

These substances are generally harmless, that is perhaps why winemakers do not need to include them on labels. Sulphites or sulfites are considered potentially harmful although they do occur naturally; the subject of low sulphur wine is covered separately.

Additives Allowed in Wine

Additives Allowed in Wine

Animal Products in Wine

Collagen: see Gelatin.

Egg white: commonly used as a fining agent used to remove astringent tannins from red wine. The egg white coagulates with the tannin, settles and can be removed by racking and/ or filtration.

Gelatine Collagen: animal tissue – a fining agent used to remove astringent tannins from red or white wines. The gelatine forms complexes that settle out and can be removed by racking and/ or filtration. Widely used to remove astringency from red wines, and to a lesser extent white wines.

Isinglass Protein derived from fish Fining agent used to remove undesirable phenolics. Useful for clarification but less commonly used than other fining agents.

Lysozyme: a natural enzyme purified from egg white. Used to control bacteria, an alternative to sulphur dioxide. Most likely to be used in making sweeter wines.

Milk and milk products: Casein is the active protein ingredient and may be used in a purified form, or skimmed milk may be used directly. Used as a fining agent to remove undesirable phenolics/coarseness, particularly from white wines. Coagulates on contact with wine or juice, allowing a very brief interaction with phenolics to form complexes that settle out and can be removed by racking and/ or filtration. Widely used and effective fining agent for white wines.

Additives in Wine

Additives are substances and chemicals added to wine that stay there and become part of the finished product.

Ascorbic acid (E300) is a natural substance but, as an additive is produced synthetically. It is used as an Anti-Oxidant and widely used in white wines to protect fresh aroma and flavour.

Carbon dioxide (also a processing aid): essentially air, produced by yeast during wine fermentation. As an additive, it is used to make inexpensive sparkling wines by carbonation as for soft drinks and can give a relatively coarse feel in the mouth.

Carboxymethyl cellulose: see Sodium carboxymethylcellulose.

Citric acid from grapes, though at lower levels than tartaric and malic acids. Adjusts the acid balance in white wines, but less commonly than tartaric and malic acids.

Dimethyl dicarbonate: a synthetic preserving and/ or sterilising agent. Rarely used alternative to sulphur dioxide.

Erythorbic acid (E315) is a natural plant product that is used as an Anti-Oxidant, as an alternative to ascorbic acid.

Grape juice including concentrated grape juice are  used for sweetening. An alternative to stopping fermentation at the desired residual sugar level. Most likely to be used in lower-priced commercial wines.

Grape skin extract are used to add colour to red wines, in order to make a better-looking red wine out of ordinary grapes.

Gum Arabic from Acacia trees, to quote product literature: “Used to provide colloidal stability in wines, therefore preventing the formation of hazes or deposits at low temperature. Reduces the risk of potassium bitartrate deposits and reinforces the action of metatartaic acid. Provides increased mouthfeel and roundness to the wine and attenuates harsh tannins in red wines.”

Lactic acid occurs naturally in wine, mainly when malolactic fermentation has occurred. It is used a adjust acid balance in white or red wines, but less commonly than tartaric and malic acids.

Malic acid from grapes is used to adjust acid balance in white wines.

Metatartaric acid is prepared by heating tartaric acid to prevent bitartrate crystallization after bottling. Rarely used as effectiveness has limited duration.

Mistelle Natural or, grape juice fortified with alcohol. Used for sweetening after fermentation or (rarely) increasing alcohol before fermentation. For sweetening, an alternative to stopping fermentation at the desired residual sugar level. Most likely to be used in lower-priced commercial wines.

More Additives

Potassium sorbate – see sorbic acid.

Potassium sulphites (E224, E225, E228) – see sulphur dioxide.

Sodium carboxymethyl cellulose (E466) derived from plant cellulose. It prevents formation or growth of crystals of potassium hydrogen tartrate in wine, hence provides an alternative means of cold-stabilising wine. The standard method of cold stabilisation involves refrigeration for temperature control. This alternative may be cheaper and reduces the carbon footprint.

Sorbic acid is a synthetic antifungal additive that prevents yeast growth, it is used to stabilise some sweeter white wines.

Sulphur dioxide (E220) is a synthetic additive that also occurs naturally on grapes. Anticrobial and antioxidant, it is almost universally used and necessary for wine to have reasonable shelf-life. See Low Sulphur Wines.

Tannins occur naturally in grapes but additives may come from chestnut, plant galls, oak or grapes. It is used to stabilise the red wine colour, build structure and mouth feel. Used to bolster wine made from low grade grapes or to make wine to winemaker’s preferred style.

Tartaric acid comes from grapes, as an additive it is usually purified from grapes or other natural sources. It is used to adjust pH and acid balance, either to make the wine more microbially-stable, or to improve balance. Most efficient and commonly used acid to adjust musts and wine. More likely to be used in warm New World areas rather than EU.

Yeast mannoproteins: yeast adds mouth-feel and texture. A shortcut to the effect normally obtained when maturing wine on lees. Yeast breakdown products contribute to creaminess and mouth-feel.

Processing Aids in Wine

Activated carbon from charcoal is used to remove colour (eg pink from a white juice) or aromas. It is also used to deal with problem wines, however also removes flavours.

Agar is made from red algae (sea plants), it can be used as a fining agent but rarely is.

Alginates, calcium and potassium salts made from brown algae (seaweeds). Used in some riddling agents, which are added to yeast used in bottle fermentation of sparkling wine, making the yeast easier to remove at time of disgorging. Probably only used in the traditional method of making sparkling wine.

Ammonium phosphates is a synthetic, simple and cheaper nutrient (nitrogen source) for yeast growth and reduce the formation of hydrogen sulphide (rotten egg gas) from nitrogen-deficient yeast. Widely used to maintain clean healthy yeast fermentation. More natural but more expensive nutrients are available in the form of yeast extracts.

Argon is purified from air, it is an inert gas that protects wine or juice from oxidation. Very effective but more expensive than nitrogen.

Bentonite Clay, when mixed with water forms a high surface area of charged particles, which bind to and remove proteins that could otherwise form hazes. Only used in white or rosé wine as tannins in red wine perform the same role. Almost universally used to prevent formation of unsightly hazes in white wines.

Calcium carbonate occurs naturally in rocks and is used for de-acidification although rarely used as it produces calcium tartrate in wine, see below.

Calcium tartrate is an allowed additive but is generally avoided or removed.

Carbon dioxide (also a processing aid): essentially air, produced by yeast during wine fermentation. As an additive, it is used to make inexpensive sparkling wines by carbonation as for soft drinks and can give a relatively coarse feel in the mouth.

Cellulose is a natural fibre from woody plant material. It is a component of some fining agents, with the overall purpose of removing coarse or bitter phenolic compounds and hence improving mouth-feel. Used in some proprietary fining agents (e.g. blends of casein, cellulose and PVPP).

Chitosan from shellfish or fungal is used for settling, racking and control of spoilage yeast.

Copper sulphate is synthetic produced and used to remove sulphide odours. Copper is also a catalyst of oxidation, so only the minimum possible amount is used.

Cultures of micro-organisms: typically yeasts and bacteria that have been isolated from successful fermentations. To ensure reliable fermentation, whether the primary fermentation carried out by yeast, or the malolactic fermentation carried out by bacteria. With careful management, indigenous yeast may give better results in some wine styles than single cultured strains, but the cultures are widely used for reliability.

Cupric citrate – see copper sulphate.

More aids

Diatomaceous earth from soft siliceous rock formed from fossilised diatoms. Filter aid, ie leesy wine or juice is mixed with the earth, then filtered: with the earth forming the filter medium. Used in larger wineries that can afford the expensive filtration equipment. Recovers good juice from juice lees that would otherwise be discarded.

Dimethylpolysiloxane: a synthetic, silicon rubber.

Enzymes: purified from micro-organisms. Pectinase is also naturally present in grapes, but may be at insufficient levels to facilitate rapid settling/natural clarification of juice or wine Widely used in white wines, some reds.

Hydrogen peroxide is a synthetic powerful oxidant that can be used to remove sulphur dioxide, thankfully only occasionally necessary.

Ion exchange resins: a synthetic de-acidifier. A more efficient method of adjusting acidity than through addition of wine acids such as tartaric. Generally larger wineries.

Nitrogen: from air, an inert gas used to protect white wine from oxidation. Widely used in white wine-making, often with carbon dioxide.

Oak barrels for storage, planks or chips inserted into tanks. Oak-derived compounds give flavour and texture to wine. Widely used in better quality red wines and some whites.

Oxygen: from air and an important yeast nutrient, added during fermentation. Also useful for removal of reductive character caused by sulphides. Fairly commonly used to manage fermentation or reduction during ferment or maturation.

Perlite: a mineral modified from volcanic rock. Used as a filter aid and an alternative to diatomaceous earth. Generally larger wineries.

Phytates comes from plants such as cereal seeds.

Plant proteins permitted as processing aids under clause 3(a) to Standard 1.3.3 . Used as fining agents as alternatives to egg white, casein or isinglass in some vegan and allergen free wines.

Polyvinyl polypyrrolidone (PVPP) is a synthetic fining agent used particularly to remove coloured material or bitterness from white wines. Expensive but useful in some cases.

Potassium carbonate: a synthetic de-acidifier that is rarely used as potassium hydrogen carbonate is more gentle.

Potassium ferro-cyanide Synthetic Removal of iron or copper. Rarely used: avoidance of metal contamination preferable to treatment.

Potassium hydrogen tartrate comes from grapes. Finely ground crystals are added to cold white wine to seed the crystallisation of natural potassium hydrogen tartrate from the wine, which could otherwise form slowly in bottle making undesirable though harmless ‘wine diamonds’. Widely used in the contact process to stabilise white wines before bottling. Not so often in red wines: they tend to stabilise naturally during maturation, and deposits in bottle are considered more acceptable.

Silicon dioxide, or silica gel is synthetic and used in combination with gelatine fining to encourage settling of the gelatine-phenolic complexes from the wine. Only occasionally used for fining.

Thiamin chloride and Thiamin hydrochloride, a natural B-complex vitamin. These may only be added to wine, sparkling wine and fortified wine to facilitate the growth of micro-organisms. Thiamin may be depleted from must by sulphur dioxide, and therefore added back when necessary to ensure reliable fementation. Eg at tirage prior to the second fermentation in sparkling wine.

Is there more?

The information here can only be an introduction to the subject of additives in wine. It is possible that some might be incorrect or incomplete: the list is not exhaustive and should not be relied upon. We would welcome your comments: Contact Us.

We acknowledge with thanks the input from Frank and his “What is in Australian Wine” specialist blog on what is in Australian wine.
Food-Standards-Agency  The most authoritive source in the UK would probably be the Food Standards Agency. The information on their website is not however easily accessed. Their objective is to ensure that EU wine regulations are enforced in the UK. Within their site they do provide a number of publications and links to these – it has to be said though that these are just the sort of thing most of us do not want to read. We simply want to be satisfied that we are drinking vegan wine without too many additives.

Bio-Dynamic Wine

Low Sulphur Wine

Organic Wine

Vegan Wine in Supermarkets

Print Friendly, PDF & Email