What Are Sulfites and Why Are They in Some Dried Fruits?
Sulfites are inorganic salts, such as sulfur dioxide ($SO_2$), commonly used as a preservative and antioxidant in food processing. Their primary function in dried fruit is to inhibit microbial growth, extend shelf life, and, most visibly, prevent browning and maintain a vibrant, fresh-looking color. Fruits that are naturally lighter in color, such as apricots, golden raisins, and apples, are most often treated with sulfites to preserve their bright appearance. Without this treatment, apricots, for example, would turn a dark, brownish color as they dry.
How to Tell if a Dried Fruit Contains Sulfites
Reading the ingredient list is the most reliable method for determining if a product contains added sulfites. Regulatory bodies like the FDA require that foods with sulfite concentrations over 10 parts per million (ppm) be labeled. Sulfites may be listed under several names or codes:
- Sulfur dioxide
- Potassium bisulfite ($E224$)
- Potassium metabisulfite ($E224$)
- Sodium bisulfite ($E222$)
- Sodium metabisulfite ($E223$)
- Sodium sulfite ($E221$)
Alternatively, you can often tell by appearance. Sulfite-free versions of light-colored fruits like apricots and pears will naturally be darker or browner, a result of oxidation that occurs during the drying process. This natural discoloration does not indicate spoilage, only that no sulfur-based bleaching agent was used.
Not All Dried Fruits Contain Sulfites
Many types of dried fruit are naturally sulfite-free or processed without added preservatives. This is particularly true for organic products, which prohibit the use of synthetic additives like sulfur dioxide. Some fruits are also less susceptible to discoloration, so they are rarely treated with sulfites. These typically include:
- Dates
- Prunes
- Raisins and sultanas (though some may be treated, most are not)
- Figs
- Goji berries
- Cranberries (often sweetened, but check labels for sulfites)
Conventional vs. Organic: A Comparison
The cultivation and processing methods for dried fruit can differ significantly, directly impacting whether sulfites are present. Here is a comparison of conventional versus organic and natural dried fruits:
| Feature | Conventional Dried Fruits | Organic & Natural Dried Fruits |
|---|---|---|
| Preservatives | Often use sulfur dioxide ($SO_2$) and other chemical additives (E220-E228) | Prohibits synthetic preservatives; relies on natural methods |
| Appearance | Bright, vibrant, and uniform in color; prevents natural browning | Often darker, more natural, and less uniform in color |
| Drying Process | May involve industrial heat drying or other chemical processes | Relies on sun-drying or gentle, low-temperature dehydration |
| Nutritional Content | Highly nutritious, but some water-soluble vitamins (like C) may be lost | Highly nutritious, with a focus on retaining natural goodness |
| Pesticides | May use synthetic pesticides and fertilizers | Grown without synthetic pesticides and fertilizers |
| Cost | Generally more affordable due to mass production | Typically higher due to more labor-intensive farming |
Potential Health Effects and How to Avoid Sulfites
For the majority of people, consuming sulfites in dried fruit is harmless and considered safe by regulatory bodies. However, some individuals are sensitive to sulfites, and for them, ingestion can trigger adverse reactions. These sensitivities are most common in people with asthma, with up to 13% of asthmatics experiencing a reaction. Symptoms can include wheezing, chest tightness, hives, and flushing, and in very rare cases, anaphylaxis.
Fortunately, for those with a sensitivity, avoiding sulfites is straightforward by choosing organic or naturally dried products. The darker appearance of these products is a key visual cue, but always check the label for explicit confirmation. You can also look for phrases like “no added sulfites” or “unsulphured” on packaging. To further confirm, some retailers, such as those promoting organic and natural foods, specifically label their products as sulfite-free.
Can You Remove Sulfites from Dried Fruit?
Some studies have shown that washing and cooking dried fruit can significantly reduce the sulfite content. For example, boiling dried apricots reduced sulfites by 44% in one study. While this is an option, it's not foolproof and may not remove enough for highly sensitive individuals. The most reliable method is to purchase products explicitly labeled as sulfite-free.
Conclusion: Choosing Your Dried Fruit
In conclusion, the claim that all dried fruits contain sulfites is false. While conventional dried fruits, particularly light-colored ones like apricots and apples, are often treated with sulfur dioxide to preserve their appearance and shelf life, many organic and naturally dried varieties are sulfite-free. For most people, the presence of sulfites is not a concern, but for individuals with asthma or sensitivity, it is best to seek out unsulphured or organic alternatives. By carefully reading ingredient labels and recognizing the natural, darker appearance of untreated fruit, you can easily make an informed choice that suits your dietary needs. For more information on sulfite sensitivity, you can consult health resources like Everyday Health to understand the potential side effects.
For additional information about the health effects of sulfites, visit the Everyday Health website.
