Free and Total Sulphur Dioxide

Fera’s leading food scientists can analyse your wine samples and quantify the levels of sulphur dioxide (SO₂) present. While naturally present in wine produced as a fermentation by-product, sulphur dioxide (SO₂) can also be added to wine during the pre bottling stage of production to preserve products during storage. SO₂ protects a winemaker’s product from the negative effects of oxidation and spoilage microorganisms.

Although common practise, throughout the world there are regulations concerning the levels of SO₂ in wines, and it is mandatory for any wine containing more than a total SO₂ content of 10 mg/L to display ‘contains sulphites’ on the label. Wines are also subject to a legal limit for SO₂, which in red wine is 150 mg/L and in white wine it is 200 mg/L. These limits are specified by the International Code of Oenological Practices (OIV Code Sheet, Issue 2015/01, XXXVII. ANNEX: MAXIMUM ACCEPTABLE LIMITS).

Fera wine testing can ensure that levels of SO₂ are within the legal limits, and also that any products which do not have the ‘contain sulphites’ label are below the 10mg/L requirement.

At Fera the test for sulphur dioxide levels in wine is undertaken with iodometric titration, and we are able to offer rapid analysis with a typical 10 day turnaround from receipt of your samples by our scientists.

Although we primarily utilise these methods within our wine authenticity analysis activities, we are able to conduct this analysis across a range of samples to provide the authenticity analysis you require. Contact us to meet your bespoke requirements.