Understanding Sulphites in Fruit
Sulphites, a group of sulphur-based compounds, serve as preservatives and antioxidants in the food industry. Their primary functions are to inhibit microbial growth, prevent spoilage, and maintain the colour and texture of foods. While sulphites occur naturally in some foods at very low levels, their presence in higher concentrations, particularly in fruit products, is almost always due to intentional addition during processing. For most people, consuming sulphites is harmless, but for a smaller percentage of the population, especially individuals with asthma, they can trigger allergic-like reactions. Therefore, identifying what fruit has sulphites is a critical step towards informed dietary choices.
Dried Fruits with Added Sulphites
Dried fruits are the single biggest source of sulphite exposure in the fruit category. The vibrant, light colours of many dried fruits are a direct result of being treated with sulphur dioxide (E220) to prevent enzymatic browning. If a dried fruit appears bright and colourful rather than its natural brownish hue, it is likely that sulphites were added.
Common dried fruits that often contain added sulphites include:
- Dried Apricots: Especially those with a bright orange colour. Organic versions are typically brown and sulphite-free.
- Golden Raisins: The light colour of these raisins is maintained using sulphur dioxide.
- Dried Peaches and Pears: These dried tree fruits are frequently heavily sulphited unless sourced from specialty or organic stores.
- Dried Apples: Conventional dried apple slices often contain sulphites to prevent browning.
- Glacé Cherries and Maraschino Cherries: These candied and processed fruits use sulphites during preparation.
- Dried Mango and Pineapple: Tropical fruits are also often treated to preserve their vibrant colour.
Fresh Fruit that May Contain Sulphites
While sulphites are not permitted on most fresh fruits intended to be eaten raw, there are a few notable exceptions and specific instances of treatment.
- Grapes: Fresh table grapes can be fumigated with sulphur dioxide gas or packed with slow-release sulphite pads to prevent decay and spoilage during storage and transit.
- Imported Tropical Fruits: Surveys in countries like Canada have found detectable sulphites on certain imported fresh fruits, including lychee, longan, and cherimoya, though the concentrations in the edible flesh are typically low.
Naturally Occurring Sulphites in Fruit
It's important to distinguish between added sulphites and the very low levels that can occur naturally. Some fruits and vegetables contain trace amounts of sulphur compounds, though these are typically not problematic for those with sensitivities unless consumed in very large quantities. The levels are significantly lower than what is typically added as a preservative.
How to Avoid Sulphites in Fruit
For those who need or prefer to avoid sulphites, there are several strategies:
- Read Labels: In many countries, food regulations mandate that added sulphites be declared on product labels if the concentration exceeds 10 parts per million (ppm). Check ingredient lists for terms like sulphur dioxide, potassium metabisulphite (E224), sodium bisulphite (E222), or simply “sulphites”.
- Choose Organic: Organic standards generally prohibit the use of sulphur dioxide preservatives. Organic dried fruits are a reliable sulphite-free option, though they will typically be darker in colour and have a shorter shelf life.
- Opt for Fresh: Choosing fresh fruit over dried or processed versions is the best way to ensure no added sulphites are present. For fresh grapes, which may have been treated, a thorough washing might help, but it is not guaranteed to remove all traces. Some fruits, like dates and prunes, are naturally dried without sulphites.
- DIY Dried Fruit: For complete control, you can dry your own fruit at home using a food dehydrator or an oven.
Dried Fruit Comparison: Conventional vs. Organic
To better understand the key differences, here's a comparison table focusing on conventional versus organic dried apricots, a common fruit with sulphite addition.
| Feature | Conventional Dried Apricots | Organic Dried Apricots |
|---|---|---|
| Sulphite Content | High; sulphur dioxide added as a preservative. | Sulphite-free; no sulphur dioxide added. |
| Colour | Bright orange or yellow, maintained by preservatives. | Dark brown or reddish-brown, a result of natural oxidation. |
| Shelf Life | Longer due to the preservative properties of sulphites. | Shorter than conventional; should be consumed more quickly or stored in the fridge/freezer. |
| Taste | Can have a slightly tangy or chemical aftertaste. | Intense, natural fruit flavour and aroma. |
| Health Considerations | May trigger adverse reactions in individuals with sulphite sensitivity, especially asthmatics. | Safer for those with sulphite sensitivity; no known risk of sulphite-related reactions. |
| Cost | Often less expensive than organic counterparts. | Can be more expensive due to shorter shelf life and production methods. |
Sulphites and Health Concerns
While the Food and Drug Administration (FDA) generally recognizes sulphites as safe, a significant minority of people, particularly asthmatics, can react negatively. Reactions can range from mild symptoms like flushing, wheezing, and skin rashes to more severe, though rare, anaphylactic responses. The precise mechanisms of sulphite sensitivity are still being studied, but one theory suggests the irritant gas released by sulphites in the stomach can trigger respiratory issues. Individuals with suspected sulphite sensitivity should consult with a healthcare professional or allergist to confirm their condition and receive appropriate dietary guidance.
Conclusion
In summary, while some fruits contain negligible levels of natural sulphur, the primary concern regarding sulphites in fruit relates to preservatives added during processing. Dried fruits like apricots, raisins, and peaches are among the most heavily sulphited products to preserve their appearance and shelf life. Fresh grapes can also be treated. For those with sensitivities, reading labels for sulphite additives and choosing organic or naturally sulphite-free versions, such as brown organic dried fruits, is the most effective strategy. By understanding which fruit products contain these additives, individuals can make informed decisions to manage their health and enjoy fruit safely.
For more detailed information on sulphite sensitivity and management, resources from organizations like Anaphylaxis UK provide valuable guidance on identifying and avoiding sulphite-containing foods.