The Low-down on Low-preservative wines

So what exactly are preservatives?

There are a number of preservatives that can be present in wine, but, the main culprit is Sulphur.

Whether you call it 'sulpher', 'sulphites', or preservative 220, preservatives in wine often cause confusion for customers.

Which preservatives are used in wine?

Sulphur dioxide (preservative 220), also known as SO2, or metabisulphate

Preservative 221 (also a metabisulphate)

Potassium metabisulphite (preservative 224) and

Ascorbic Acid (300)

can all be added during the wine production process.

What role do preservatives play in wine?

Preservatives help protect wine from spoilage, which occurs due to oxidation and build up of bacteria. 

The preservative used can be in a number of different forms; sulphur salts or sulphur dioxide. Sulphur is used in many stages of the wine making process such as grape harvest, to pre-bottling.

During the wine making process, compounds in the wine can build up resulting in undesirable aromas, flavours or even colours. The sulphites help to 'bind' these compounds and prevent contamination and lessen bacterial growth.

What can preservatives due to the body?

Adverse effects to sulphites include flushing, wheezing, coughing, rash and extreme cases difficulty breathing. While a true allergic reaction is rare, many people experience adverse effects from wine and waking up the next day feeling unwell is a common side effect.

How do they measure preservative levels?

In Australia the level of sulphur dioxide is measured as parts per million (ppm). wines can have as much as 400ppm. Organic and Biodynamic wineries follow strict standards and can have no more than 120ppm, but are usually well below this limit.

For health and allergy considerations it is the free sulphur level that is the main concern. The figure usually quoted is made up of both the bound sulphur dioxide and the free sulphur dioxide, which added together give the total sulphur dioxide level.

So what's the difference between preservative free and low preservative?

Sulphur dioxide is a natural product of fermentation, however this is already bound up in the wine and is in minute quantities, so likely to pose little threat to health. 

Because 'Preservative Free' wines still have some sulphites, but no sulphur dioxide has been added to the wine. The term 'No Preservatives Added' may be used

Differences in the levels of sulphites (ppm) varies due to a variety of factors such as the type of grape, alcohol levels, acidity, tanins and even packaging and handling. This means that each label will have differing levels of sulphites.

However, as Organic and Biodynamic wines follow strict guidelines (of less than 120ppm) you can be sure by looking at the back label that the wine was produced with minimal intervention.

We are happy to stock at Guilt Free Wine a large selection of only certified organic and biodynamic wines, which are naturally low in sulphites and we also have wines that are exclusively preservative free.

Does being preservative free affect the flavour?

Often the preservatives, additives and fillers drastically change the flavour profile of the wine. You will find that low preservative and preservative free wines are much cleaner and taste refined, exactly how nature intended. 

How long do preservative wines keep for?

Preservative free wines are best drunk within 2-3 days, however using a vacuum seal can prevent further oxidation after the bottle is opened and extend the life of the wine for another 1-2 days.

Most organic and biodynamic wines should be enjoyed within 3 days.

Can you cellar a wine that has no preservative added? 

Yes. Look at the 'wine specifications' on our product pages, which indicate the amount of time that is recommended for cellaring.

White wine would be much harder to cellar long term (7+ years) because it doesn't have the tannins that red wine has and is usually lower in alcohol than red wine.

Why does the level of preservative vary so much from one bottle to another?

There are many factors influencing the amount of preservative needed or added. Some of these are outlined here:

Alcohol -The higher the alcohol, the less preservative needed because alcohol is a natural preservative.

Tannins - Red wines have higher levels of tannins which are also a natural preservative (extracted from the red grape skins during fermentation). Oak tannins can also be found in wine that spends time in oak barrels.

Quality, Care & Handling – Fruit and wine that is handled carefully in the vineyard and winery has less exposure to elements that cause spoilage. Meticulously clean winemaking equipment and premises also make sulphur dioxide less necessary.

Healthy grapes of high quality with concentrated flavours and good acid also needs fewer preservatives. A winemaker aiming for a premium quality wine will carefully handle this wine to ensure balance of flavour and aroma.

Packaging/Closure - Stelvin or screw cap closure on bottled is a more perfect seal than the cork or cask, and hence less sulphur dioxide should be needed.

Labelling laws in Australia

If the detectable amount of preservative is less than 10 ppm, labelling laws in Australia do not require anything about preservative to be mentioned on the label.

Preservative Free wines have no Sulphur dioxide (additives 220 or 224) added, but may still contain minute amounts of naturally occuring SO2, as long as it measures under the allowable threshold of 10 parts per million. So, more accurately, they are called "No Added Preservative" wines. For simplicity the two terms are used interchangeably when the level is below this accepted allowable threshold.

SOURCES:

ASCIA (2019), Alcohol Allergy Resource

ASCIA (2021) Sulphite Sensitivity

Allergol Select (2018) Allergic and intolerance reactions to wine

Clinical and Translational allergy (2011) Risk of allergic reactions to wine, in milk, egg and fish-allergic patients

Government of Canada (2011) Sulphite Allergy Resource

Journal of Allergy and Clinical Immunology (1999) Wine induced Asthma: a placebo controlled assessment of its pathogenesis