Sulphites are compounds often used as preservatives in cider.
What Are Sulphites?
Sulfites are inorganic salts that have antioxidant and preservative properties. Compounds capable of producing sulphite have been used for around 2000 years as food additives to prevent growth of microorganisms, enzymatic and non-enzymatic browning, bleaching agents, antioxidants or reducing agents. Historically sulphites were used on fruit to prevent discolouration, and on salad vegetables to prolong life. Examples of chemicals used are Sulphur doxide, Sodium Sulphite, Sodium metabisulphite, Potasssium metabisulphite, Sodium bisulphite and Potassium bisulphite. It is important to note also that sulphites are a natural product of the fermentation process, created by the yeat metabolising sulphur in the fruit. Sulphites are used in beverages in an number of ways:
- Sterilisation of brewing equipment and cleaning of bottles
- To prevent discolouration of stored fruit/juice
- To kill off any wild yeasts on the fruit, allowing a standard culture to be introduced
- Premature stopping of fermentation before all the sugar is used, giveing a sweeter product.
- To prolong shelf life of packaged product.
Different producers introduce sulphite at different stages in the process: some may simply use it to sterilise the fermentation gear prior to production, with little or no sulphite reaching the final product. Others may inject it into the bottles at packaging. Unfortunately little or no distinction is made on labels as to how sulphites are used in any specific product. This is partly because sulphites can cause some people to become sensitised: to those individuals ANY sulphite is too much.
Carefully read the ingredients labelling next time you pour/drink a cider - it will usually state Sulphites have been added. Sometimes it will say for freshness, but this is considered a lame attempt to attempt to justify it. It also will not state how much sulphite has been added. This could be anything from 10mg/litre to 450mg/litre.
Sulphites may be listed on the label under their "E" numbers:
EC No. Name
E 220 Sulphur dioxide
E 221 Sodium sulphite
E 222 Sodium hydrogen sulphite
E 223 Sodium metabisulphite
E 224 Potassium metabisulphite
E 226 Calcium sulphite
E 227 Calcium hydrogen sulphite
E 228 Potassium hydrogen sulphite
Maximum level of sulphite allowed in the UK in Cider is 200mn/l- expressed as SO2 (Sulphur dioxide) from ALL sources
So what is so bad about sulphites?
Sulphites are a problem from a "traditionalist" point of view, and a medical point of view.
In manufacturing, they can be used to kill off the fruit's natural yeast, enabling its replacement with a standard culture. This obviously detracts from the "naturalness" of the the cider: well produced cider should be capable of fermenting using its own natural yeast. However this has to be offset against the reduced risk of culture infection: cider fermented with a culture will be more consistent in quality, but will never achieve the quaity of a top class real cider. Sulphites can also be used to sterlise the cider prior to packaging to prevent further fermentation or maturation of the product.
Medically, sulphites are associated with sensitisation. This can happen at any time, sometimes the intial symptoms not showing until the subject is forty or fifty. Symptoms include include a large array of dermatological, pulmonary, gastrointestinal, and cardiovascular effects. Asthmatics in particular can be badly affected. Details of sensitivity seem hard to come back, though one USA survey indicated 1% of their population, and 5% of asthmatics show a reaction.
Sulphites, both natural and introduced, have been part of our diet for a long time, and for most people there is no medical risk. For years sulphites have played a role in preserving food, preventing microbial infection and preventing food poisoning
Sulphites are not only used in industrial cider. Most, if not all alcoholic beverage makers will use sulphites - even if only as the ubiquitous "camden tablets" - to disinfect their fermentation equipment between production batches. even this minor use requires the bottles to be labelled "containes sulphites". However, other producers will use it at much later stages in production, and that is when there is a risk to the taste and quality.
There is evidence (see refernece linked below) that the presence of sulphite can incerase the production of acetaldehyde during cider manufacture
- Sulfites: Separating Fact from Fiction
- Wiki article on sulphites
- Food intolerance network factsheet
- The Miscellaneous Food Additives Regulations 1995 CONDITIONALLY PERMITTED PRESERVATIVES AND ANTIOXIDANTS
- The Effect of SO2 on the Production of Ethanol, Acetaldehyde, Organic Acids, and Flavor Volatiles during Industrial Cider Fermentation