Is there sulphur in bacon? Understanding natural and added sulphites

November 21, 2025 •

5 min read

According to a study published in ScienceDirect, meat products are significant contributors to overall dietary sulphur intake, and this includes bacon. The presence of sulphur in bacon, however, comes from two main sources: naturally occurring sulphur-containing amino acids in the meat and, in some cases, added sulphite preservatives. Understanding the difference is key to understanding what you consume.

Quick Summary

The presence of sulphur in bacon stems from two sources: natural amino acids in the pork itself and, for some varieties, added sulphite preservatives used during processing. These additives must be clearly labelled on the packaging. Consumers on low-sulphur diets or with sensitivities should check labels for sulphite additives.

Key Points

Natural Sulphur: Bacon contains naturally occurring sulphur as part of the amino acids methionine and cysteine found in the pork.
Sulphite Additives: Some processed meat products, though typically not whole-cut bacon, may contain added sulphite preservatives, but regulations vary by country.
Check the Label: Consumers with sensitivities should always check the ingredient label for sulphite additives (E220-E228), which must be declared above a certain threshold.
Health Effects: While natural sulphur is benign, sulphite additives can trigger allergy-like reactions, especially in asthmatics.
Curing Agents: The primary preservatives in cured bacon are nitrates and nitrites, which are different from sulphites.
Uncured Bacon: 'Uncured' bacon uses natural curing agents like celery powder, which also contains natural nitrates and nitrites.

The Dual Sources of Sulphur in Bacon

The question of whether there is sulphur in bacon is more complex than a simple 'yes' or 'no.' It requires an understanding of both the fundamental chemistry of meat and the modern food production process. Essentially, sulphur is present in all meats, including bacon, in two forms: as a natural component of the animal's protein and as an additive used for preservation and colour.

Natural Sulphur in Meat

The primary, natural source of sulphur in meat is the presence of sulphur-containing amino acids, specifically methionine and cysteine. These are building blocks of protein and are essential for animal and human nutrition. Since pork is a protein-rich food source, it naturally contains these amino acids. The sulphur content can vary depending on the animal's feed and the cut of meat, but it is an inherent and unavoidable part of all meat products. This natural sulphur is part of a healthy diet for most people and does not typically pose health issues, except for those with specific metabolic disorders or sensitivities.

Sulphite Additives in Processed Meats

The second source of sulphur in bacon comes from added preservatives called sulphites (or sulphur dioxide), identified by codes E220-E228. These are chemicals that food manufacturers add to many processed foods and drinks for several reasons:

Preservation: Sulphites are effective antimicrobial agents that inhibit the growth of mould, yeast, and bacteria, extending a product's shelf life.
Antioxidant: They prevent the browning and discolouration of food, helping to maintain an appealing, fresh appearance.
Colour Stabilisation: In cured meats, sulphites can help stabilise the pinkish colour, which consumers associate with freshness.

It's important to note that while some meat products, like fresh sausages in certain regions, may contain added sulphites, the regulations regarding their use vary significantly by country. In some places, like the USA, added sulphites in meat are banned entirely. Conversely, in Australia and New Zealand, their use is permitted in specific processed meat products, but not in whole cuts like bacon. Consumers must check food labels carefully, as any sulphite presence above a certain threshold must be declared.

Natural vs. Added Sulphur: A Comparative Look

To better understand the distinction, let's compare the properties and implications of natural and added sulphur sources in bacon.


Feature	Natural Sulphur (from Amino Acids)	Added Sulphites (E220-E228)
Source	Inherent part of the pork's protein structure.	Chemical additives included during processing.
Function	Essential nutrient for human health.	Preservative, antioxidant, colour stabiliser.
Health Impact	Required for normal bodily function; generally harmless.	Can trigger sensitivities, particularly in asthmatics.
Labelling	Not typically mentioned on the label as an ingredient.	Must be declared on the ingredient list if concentration exceeds a certain level.
Purpose in Bacon	Found in all bacon as a fundamental component.	Not permitted as an additive in whole-cut bacon in many regions like the USA, but may appear via other ingredients or in other processed meat types.

The Role of Nitrates and Nitrites

While discussing preservatives in bacon, it is also essential to address the role of nitrates and nitrites. These are curing agents commonly used in the production of traditional bacon. Nitrates and nitrites are salts that are added to meat to preserve it, inhibit bacterial growth (especially Clostridium botulinum), and enhance flavour and colour. It is the reaction between nitrates/nitrites and the meat's proteins that gives bacon its characteristic pink hue and distinct flavour. Many consumers confuse sulphites with nitrites, but they are different compounds with different functions and regulations governing their use. Some bacon is cured with celery powder, which naturally contains nitrates, allowing it to be labelled as 'nitrate-free'.

Conclusion

So, is there sulphur in bacon? Yes, but the key is to distinguish between its natural and added forms. All bacon contains natural sulphur from the amino acids present in the pork. The presence of added sulphite preservatives, however, is regulated and depends on the specific processing methods and country. For consumers with sensitivities or those following a low-sulphur diet, checking labels is the best practice. Understanding that bacon contains both natural and potentially added compounds is important for informed dietary choices.

Can you buy bacon without any added sulphur?

Yes, because sulphites are not a permitted additive in whole-cut cured bacon in many countries, and any added sulphites would originate from other ingredients, if at all. The natural sulphur from amino acids, however, will always be present, as it is a basic component of the meat. For those sensitive to preservatives, checking labels and opting for products explicitly marked as 'uncured' or 'nitrate/nitrite-free' might be the safest option, although these still contain natural nitrates from sources like celery powder.

Lists for Informed Choices

Common Sulphite Additives (E numbers to look for):

E220: Sulphur dioxide
E221: Sodium sulphite
E222: Sodium bisulphite
E223: Sodium metabisulphite
E224: Potassium metabisulphite
E225: Potassium sulphite
E228: Potassium bisulphite

Foods that may contain added sulphites:

Dried fruits (major source)
Wine and cider
Some condiments like mustard
Certain processed meats (depending on regulations)

Examples of sulphur-rich foods (natural):

Allium vegetables (onions, garlic)
Cruciferous vegetables (broccoli, cauliflower)
Eggs (yolk)
Dairy products

Key Takeaways

Natural vs. Additive: Bacon naturally contains sulphur from amino acids, but not all bacon has added sulphites.
Check Labels for Additives: Regulations require sulphite additives to be declared on packaging if they exceed 10mg/kg.
Health Considerations: While natural sulphur is important, sulphite additives can cause allergic-type reactions in sensitive individuals, especially those with asthma.
Not a Universal Preservative: Sulphites are not permitted in whole cuts of meat like bacon in many jurisdictions, including the USA.
Curing vs. Sulphites: The primary preservatives in traditional bacon are nitrates and nitrites, not sulphites.
Know Your Meat Source: Processed, comminuted meat products (like some sausages) are more likely to contain added sulphites than whole-cut, cured bacon.
Uncured Alternatives: So-called 'uncured' bacon still uses curing agents like celery powder, which contain natural nitrates and nitrites.

Authoritative Source

For more information on food additives and regulations, consult the official Food Standards Australia New Zealand website: FSANZ - Food Additives

Frequently Asked Questions

Yes, all bacon contains natural sulphur because it is a fundamental component of the amino acids (methionine and cysteine) found in the pork's protein.

Generally, no. In many countries, regulations prevent the addition of sulphite preservatives to whole-cut cured meats like bacon, though rules vary. Sulphites are more commonly found in other processed meats and are added for different purposes than the nitrites typically used for curing bacon.

Sulphur is a chemical element naturally present in many foods, including meat protein. Sulphites, on the other hand, are chemical compounds (e.g., sulphur dioxide) used as food additives for preservation and antioxidant purposes.

Some individuals, particularly those with asthma, are sensitive to sulphites and can experience allergic-like symptoms, including breathing difficulties, headaches, and skin reactions. These are typically idiosyncratic or irritant effects, not true allergies.

Food labels must declare sulphites as an ingredient if the concentration exceeds 10mg/kg. Look for E-numbers E220-E228 or words like 'preservative (sulphur dioxide)' in the ingredients list.

While 'uncured' or 'nitrate-free' bacon is unlikely to contain sulphite additives, it will still have natural sulphur. These products are typically cured using naturally occurring nitrates from sources like celery powder, rather than synthetic ones.

Nitrates and nitrites are used to cure bacon to prevent bacterial growth and maintain colour, a process distinct from sulphites' use as general preservatives in other foods. Sulphites are not used for this specific purpose in bacon production in most regions.