Sulfur dioxide dosage

Sulfur dioxide (SO₂) is a colorless, pungent, and reactive gas that has long been used as a food additive and preservative. Its antimicrobial and antioxidant properties make it a widely used agent in the food industry, particularly in the preservation of wine, dried fruit, and fruit juices. However, due to its potentially harmful effects on health, its concentration in consumer products must be strictly controlled.

Sulfur dioxide measurement is essential to verify that foodstuffs comply with the maximum permitted levels set by European and international regulations. It is also crucial in the environmental sector for monitoring industrial emissions and air quality.

Analytical principle

Several analytical approaches are used to determine the sulfur dioxide concentration according to the matrix:

• Iodometry : a classic titration method based on the oxidation of sulfur dioxide, used in oenology and agri-food.
• Distillation followed by titration : reference method in some laboratories to isolate free and total SO₂.
• Enzymatic methods : rapid and specific alternatives, adapted to food matrices.
• GC-MS (gas chromatography coupled with mass spectrometry) : used for precise and sensitive analyses, particularly in complex matrices or in the environment.

These techniques guarantee reliable and reproducible results, adapted to traceability and regulatory compliance requirements.

Industrial applications

Sulfur dioxide measurement is applicable to many fields:

• Food industry : control of SO₂ levels in wines, beers, juices, dried fruits, jams, sauces and processed products.
• Nutraceuticals : securing plant-based ingredients and food supplements.
• Oenology : precise monitoring of free and total SO₂ levels in wines to ensure their microbiological and organoleptic stability.
• Environment : measurement of sulfur dioxide emissions in ambient air and industrial effluents, as part of air pollution monitoring.

Affected matrices

The most frequently analyzed matrices include:

• Wines and fermented beverages
• Dried fruit (apricots, raisins, figs)
• Fruit juices and nectars
• Jams, sauces and canned foods
• Dietary supplements and herbal formulations
• Air samples and industrial emissions
• Water and effluents contaminated by SO₂

Quality and regulatory issues

Controlling sulfur dioxide addresses several major challenges:

• Regulatory compliance : adherence to maximum limits set by the European Union, the Codex Alimentarius and international standards.
• Consumer protection : prevention of adverse reactions, particularly in people with asthma or sensitivity to sulfites.
• Organoleptic quality : control of concentrations in wine and food products to preserve taste, color and stability.
• Environmental monitoring : monitoring of industrial atmospheric emissions, in connection with the European directive on air quality.

YesWeLab support

YesWeLab offers comprehensive support for sulfur dioxide analysis through its network of certified and accredited partner laboratories (ISO 17025, COFRAC). We provide:

• A selection of the most suitable methods (iodometry, GC-MS, distillation, enzymatic) depending on your matrices.
• Scientific expertise to interpret the results and guarantee their conformity.
• An intuitive digital platform for managing your samples, real-time tracking and rapid receipt of results.
• Reliable and reproducible analyses, meeting national and international standards.