Despite the advantages, the use of sulphur dioxide as a food preservative has raised health concerns, particularly regarding allergic reactions in certain individuals. Some people, particularly those with asthma, may experience respiratory issues or other adverse effects when consuming foods containing SO₂. As a result, regulatory agencies in many countries, including the United States Food and Drug Administration (FDA) and the European Food Safety Authority (EFSA), have established limits on the amount of sulphur dioxide that can be used in food products. Moreover, items containing sulphites (the salts of sulphur dioxide) must be properly labeled, ensuring that sensitive individuals can make informed choices.
In conclusion, E621, or monosodium glutamate, serves primarily as a flavor enhancer rather than a traditional preservative. While it enhances the taste of many processed foods, contributing to their palatability and potentially reducing food waste, it does not inhibit spoilage or extend shelf life in the same way traditional preservatives do. The safety of MSG has been affirmed by numerous health authorities, but ongoing discussions about food additives highlight the importance of consumer choice and transparency in labeling.