What is Preservative 220?
Preservative 220 is the food additive code for sulphur dioxide (SO2), a colorless gas with a pungent, suffocating odor. As a food additive, it acts primarily as an antioxidant, antimicrobial agent, and bleaching agent. The use of sulphur dioxide in food preservation is a long-standing practice, with historical records dating its use in winemaking back to the ancient Romans.
Sulphur dioxide and other sulphite-based additives (E221–E228) are used to prevent food spoilage by inhibiting the growth of yeasts, molds, and bacteria. Its antioxidant properties prevent discoloration, especially in light-colored foods like dried fruit, and protect the flavor and stability of beverages like wine and beer.
How Preservative 220 Functions in Food
Sulphur dioxide is versatile and effective in extending the shelf life and enhancing the quality of various food products. Its primary functions include:
- Antioxidant: It prevents the oxidation of food, which is the process that causes fruits to turn brown and wine to lose its flavor.
- Antimicrobial: By inhibiting the growth of bacteria and other microorganisms, it prevents food from spoiling prematurely.
- Bleaching Agent: It is used to maintain the vibrant, light color of products like dried fruits.
- Flavor Protection: In winemaking, it protects the wine from spoilage and minimizes volatile acidity, ensuring the final product retains its desired taste.
Common Foods Containing Preservative 220
Many common food and beverage products contain sulphur dioxide as a preservative. These include:
- Dried Fruits: Dried apricots, raisins, and figs are often treated with E220 to prevent browning and spoilage.
- Wine and Beer: Sulphites are used to prevent oxidation and inhibit unwanted bacterial growth during the fermentation process.
- Fruit Juices and Cordials: E220 helps preserve freshness and color in various fruit drinks.
- Sausages and Processed Meats: Permitted in some comminuted meat products to control microbial growth.
- Pickled Vegetables: Items like pickled onions and gherkins use E220 to maintain quality.
- Canned Foods: Used to preserve the color and flavor of canned fruits and vegetables.
Is Preservative 220 Safe to Consume?
For the majority of the population, consuming sulphur dioxide within regulated levels is perfectly safe. Regulatory bodies like Food Standards Australia New Zealand (FSANZ) and the European Food Safety Authority (EFSA) set strict maximum limits for its use in various foods to ensure safety. The EFSA did update its assessment in 2022, concluding that sulphites could pose a safety concern for individuals consuming high levels in their diet.
However, a small subset of the population, particularly those with asthma or severe allergies, can be sensitive to sulphites. Reactions can range from mild, allergy-like symptoms to more severe respiratory issues, including wheezing, chest tightness, and difficulty breathing. In very rare cases, anaphylactic shock can occur. Because of this, food products containing added sulphites at concentrations of 10mg/kg or more are required by law to declare their presence on the label.
Comparison: Sulphur Dioxide vs. Natural Alternatives
| Feature | Sulphur Dioxide (E220) | Natural Alternatives (e.g., Vitamin C, Rosemary Extract) |
|---|---|---|
| Effectiveness | Highly potent antimicrobial and antioxidant; very effective at preserving color. | Varies widely by substance; effective in specific applications but often less powerful than E220. |
| Application | Broadly used across multiple food categories, from dried fruits to wine and meat products. | Usage is often specific to the food item; some work better for preserving color, others for preventing microbial growth. |
| Health Impact | Generally safe for most, but triggers reactions in sulphite-sensitive individuals, especially asthmatics. | Typically considered safe and without widespread issues, though certain individuals may have sensitivities. |
| Labeling | Must be declared by name or E-number (220-228) on packaged food labels if present above 10mg/kg. | Often labeled by name (e.g., ascorbic acid, rosemary extract), which may be perceived as a 'cleaner' label by consumers. |
| Consumer Perception | Viewed with caution by some consumers due to potential side effects and link to synthetic additives. | Often preferred by consumers seeking more 'natural' or 'clean-label' products. |
Finding Sulphite-Free Products
For those with sensitivities, avoiding preservative 220 requires careful label reading. Look for products specifically labeled 'sulphite-free' or 'no added sulphites,' especially for dried fruits and wine. The additive can also appear as other sulphite codes (E221-E228) or as the ingredient 'sulphur dioxide'.
Many natural food stores and online retailers offer sulfite-free options for products like dried apricots, which can be naturally darker in color than their sulphurised counterparts. Some producers also use alternative preservation methods, such as flash pasteurization or natural extracts like ascorbic acid (Vitamin C) and rosemary extract, though these may have different effects on the product's taste, texture, and shelf life.
Conclusion
Preservative 220, which is sulphur dioxide, is an ancient and effective food additive used to preserve and protect a vast array of food and drink products from microbial spoilage and oxidation. While considered safe for most consumers within regulated limits, it poses a notable health risk for sulphite-sensitive individuals, particularly those with asthma. For this reason, legal labeling requirements mandate its declaration on food packaging. Awareness of this ingredient is crucial for those who experience adverse reactions, empowering them to make informed dietary choices. The move towards 'clean-label' foods has also driven some producers to explore and adopt natural alternatives, though E220 remains a cornerstone of food preservation for its reliability and efficacy.
