Why are there preservatives
in a bottle of wine?
As their name suggests, preservatives help to preserve wine, thus ensuring it ages as well as possible in your cellar. How do they do this? By performing 3 key functions.
Preservatives,
Antioxidants, antiseptics and refermentation prevention: find out what preservatives are used for in wine and their specific characteristics.
L-ascorbic acid, sulphites, potassium sorbate, lysozyme or DMDC: these names, which may appear on a wine label, all belong to the preservative family. They guarantee a wine’s stability, aromatic quality and good keeping throughout its life cycle. To help you understand more precisely what preservatives are used for in wine and their specific characteristics, this guide answers all your questions!
Why are there preservatives
An invaluable antioxidant role
In oenology, certain preservatives (such as sulphites or L-ascorbic acid) are used above all to protect wine from oxidation. This means they protect it from the harmful effects of oxygen, which naturally tends to alter the colour and taste of wine.
Genuine antiseptic power
Certain preservatives, such as sulphites, have proven effectiveness in controlling micro-organism populations at several stages in the winemaking process. This winemaking aid prevents the proliferation of yeasts or bacteria which could cause unpleasant flavours to emerge when the wine is tasted.
The ability to prevent undesirable refermentation
When used in a sweet white or red wine (such as a mellow or syrupy wine), other preservatives prevent any further alcoholic fermentation. To do this, they stop the growth of the yeasts that could cause unwanted refermentation once the sweet wine has been bottled, because of its residual sugars. This is particularly true of potassium sorbate.
For its part, lysozyme prevents any undesirable malolactic fermentation. This type of fermentation adds roundness on the palate by transforming malic acid into lactic acid. However, for some wines, it is the acidity that the oenologist wishes to emphasise. This is where lysozyme comes into play, stopping the reproduction of lactic acid bacteria.
In wine, DMDC (dimethyl dicarbonate) prevents both alcoholic and malolactic refermentation.
Do preservatives in wine influence its taste?
Whatever their exact role, the purpose of all preservatives is to protect the quality of a wine, without in any way altering its taste, aromas or textures. Whether it’s a red, white, rosé or sparkling wine, winemakers always take care to add only strictly necessary preservatives, in accordance with rigorously applied oenological standards.
Do preservatives in wine influence its taste?
As you may have already realised, there are different types of preservatives in wine.
- Those that act as antiseptics, starting with sulphites. Sulphites can be present in wine in 3 different forms: sulphur dioxide (E220), potassium bisulphite (E228) or potassium metabisulphite (E224). They all come from sulphur, a mineral element, and are naturally produced in any fermentation (the essential step in transforming grapes into wine!).
- Those that act as antioxidants. These include not only sulphites, but also ascorbic acid (E300), which you may know better as vitamin C: yes, it’s a natural component of many fruits and vegetables!
- Those that help combat undesirable refermentation. These include DMDC (E242), potassium sorbate (E202) (a form of sorbic acid found in rowan berries), and lysozyme (E1105) (an enzyme inherent in many living organisms, such as in egg white or human tears)!
Apart from oenology, can these preservatives be found in other sectors?
As well as being an ingredient in wine, all these preservatives are used as additives in the food processing industry to make beverages (fruit juices, soft drinks, ciders, etc.), preserves, baby food, fresh pasta, jams, dairy products, spreads, mature cheeses, and much more!
You now know the main points to keep in mind about preservatives in wine. Like other oenological products (stabilisers, acidity regulators and packaging gases), the purpose of preservatives is to guarantee the quality of your tasting experience!
Oenology
The science of good wine
