E227 / Preservatives
Calcium hydrogen sulfite
Safety in brief
Safe
Recorded EatMatrix rating, not a new clinical review. The amount, your sensitivities and country rules still matter.
- Watch for
- Sulfite-sensitive people can have allergy-like reactions, including breathing symptoms. Many affected people also have asthma; asthma alone does not establish sulfite sensitivity.
- Our advice
- Check for sulfites on the label if you have a diagnosed sensitivity. Discuss suspected food-related breathing reactions with your clinician; do not try an oral challenge yourself. A country’s permission or labelling threshold cannot guarantee that a food suits you.
What it is
Calcium hydrogen sulfite (chemical formula Ca(HSO3)2) is a sulfite preservative used in winemaking, fruit juices, and pickled vegetables to slow oxidation and microbial spoilage. It releases sulfur dioxide (SO2), which acts as the active antimicrobial and antioxidant component. It's separately used in the paper industry to help break down wood pulp, but that is not a food application. Food use is regulated, and sulfite-sensitive individuals, including some people with asthma, may experience allergic-type reactions.
Also appears on labels as: Calcium hydrogen sulfite, Calcium bisulfite, Calcium metabisulfite (in solution), Ca(HSO3)2, E227, E 227, E-227, Sulfur dioxide calcium salt, Calcium bisulphite, Food preservative calcium hydrogen sulfite, Calcium metabisulphite, INS 227.
Dietary information
- Vegan
- Yes
- Halal
- Yes
- Gluten-free
- Yes
- Allergens
- Caution
Recorded ingredient information. Check the product label or certification: sources, other ingredients and cross-contact can vary.
Research & body effects
Sulfites: sensitivity and longer-term exposure
What can happen in the body
Sulfite-sensitive people can have allergy-like reactions, including breathing symptoms. Many affected people also have asthma; asthma alone does not establish sulfite sensitivity. Sulfites help preserve food and its colour. Their practical benefit is preservation; that does not make them a nutrient you need to seek out.
FSANZ considers current food levels unlikely to pose a risk to most consumers, while recognising sensitive people and uncertainty in the older daily-intake assessment. EFSA’s European assessment raises concerns at higher estimated intakes. These authorities assessed different exposure data and assumptions.
FSANZ consumer guidance, updated November 2025 · EFSA safety assessment, 2022; corrected November 2025
What changed in the newer EFSA report
EFSA withdrew its temporary daily-intake limit in 2022 because the evidence remained inadequate to set one. The November 2025 correction revised exposure calculations and left that opinion’s conclusion unchanged.
A separate November 2025 report modelled six scenarios using possible changes to food-use limits. It estimated lower exposure in several scenarios. Some calculations also excluded measurements above the proposed limits or suspected illegal uses, so the decrease cannot be read as a measured improvement in people’s health. This was an exposure model, not a new human trial or a legal change.
EFSA exposure update, November 2025. Report methods, discussion and conclusion checked; the separate spreadsheet annex has not been fully reviewed here.
EatMatrix’s reading
Sensitivity, long-term dietary exposure and legal permission answer different questions. Group-level exposure modelling does not prove that this individual salt causes disease. Check for sulfites on the label if you have a diagnosed sensitivity. Discuss suspected food-related breathing reactions with your clinician; do not try an oral challenge yourself. A country’s permission or labelling threshold cannot guarantee that a food suits you.
Clinical guidance on the risks and interpretation of oral challenges.
Selected sources checked . The 2022 opinion’s corrected version was used. Indexed challenge records showed no linked correction or retraction in this check; that is not a complete version audit. Where present, 2026 cohort findings below remain separate. This review does not replace a personal assessment or complete every country’s food-use rules.
Selected research on E227
How to read study types- Dietary exposure estimateEFSA models alternative limits for sulfur dioxide and sulfites
Six scenarios explored possible food-use limits. Several estimated lower exposure, but changes in which measurements were included prevent a simple comparison with 2022. This modelling is neither a human health trial nor a change in law.
- Regulator reviewEFSA follow-up review of sulfur dioxide and sulfites
Industry supplied no new biological or toxicological data addressing the gaps, and the literature did not resolve them. EFSA withdrew its temporary daily-intake limit and raised concern at estimated higher exposures. The November 2025 exposure correction left the conclusion unchanged.
Publisher amendment:
- Regulator reviewEFSA re-evaluation of sulfur dioxide and sulfites
Kept a safe daily limit of 0.7 mg per kg of body weight but made it temporary because the data were limited. Estimated intake was above it in all age groups.
Earlier source summaries checked ; latest additions checked . See the detailed research section for what was read and the remaining limits. This is a selection of sources, not a complete literature review. Authority assessments apply to the uses and places they cover.
Health notes from our ingredient record
- Can trigger reactions (flushing, hives, wheezing, or in rare severe cases anaphylactoid symptoms) in sulfite-sensitive individuals, especially some people with asthma.
- Labelling rules and thresholds depend on the market and food. See the checked country sources below.
Other references from our ingredient record
These links come from the original ingredient record. They are separate from the source reviews above and have not all been checked for the exact ingredient, amount consumed or claim. Dates are shown newest first.
- Scientific Opinion on the re‐evaluation of sulfur dioxide (E 220), sodium sulfite (E 221), sodium bisulfite (E 222), sodium metabisulfite (E 223), potassium metabisulfite (E 224), calcium sulfite (E 226), calcium bisulfite (E 227) and potassium bisulfite (E 228) as food additives — EFSA Panel on Food Additives, EFSA Journal (2016). Official EFSA scientific opinion (bibliographic reference, imported 2026-10-13). It covers the additive as a group assessment and is not an individual human study; read the opinion for its findings.
Country rules
Country checks for E227
Permission depends on the market, type of food, amount and conditions. A scientific opinion or an E-number alone does not establish a legal use. These checks are separate from the stored EatMatrix rating.
Compare all eight markets and their sources
| Market | What is checked |
|---|---|
| European Union | Regulation (EC) 1333/2008, Annex II Part B, version , contains the exact code E227: Calcium hydrogen sulphite. Listing alone does not allow every food use. Part E food categories, limits, specifications and applicable later acts still need a product-specific check. Source read: . |
| Great Britain | The FSA register record for E227 (Calcium hydrogen sulphite) lists “Authorised” in England, Scotland and Wales. Register updated: 01 April 2025; record checked: . Food-specific conditions and specifications still need a separate legal check. |
| United States | Complete current-use review pending. Any scoped provision in the label guide above applies only to the stated use. FDA explains the applicable food-additive and GRAS framework. |
| Northern Ireland | Review pending. Check the applicable EU rules and territory arrangements; the GB register alone does not establish this status. FSA guidance is a starting source, not a verified permission for this entry. |
| Canada | No exact named entry located in the reviewed additive lists No exact named food-additive entry was located in the 15 current lists for Calcium Bisulphite; Calcium Hydrogen Sulphite. Potassium and sodium bisulphites are different salts. EatMatrix reading: Do not claim a permitted additive use from this review. Exact preparation, intended use and any applicable separate legal provision need confirmation; this table result is not a toxicology verdict or proof of a universal ban. Name and category review: . This describes the legal source check, not a finding that the ingredient is safe, unsafe or untested. Sources and names checkedNames checked: Calcium hydrogen sulfite; Calcium Bisulphite; Calcium Hydrogen Sulphite. All 15 Health Canada permitted-additive lists were checked by exact name, with the reviewed alternatives above. E-numbers alone are not Canadian ingredient names. The Justice Canada consolidation read was current to 21 September 2026. A complete product decision also requires its composition, specifications, intended food and use, quantities, applicable separate provisions and any later changes. |
| Australia | Exact permission still unresolved. The selected Schedule 15 rows name sulfur dioxide and sodium/potassium sulfites, not this calcium salt. Their limits cannot be transferred to E227. This scoped check does not establish a blanket ban. Label check: added sulphites at 10 mg/kg or more require a declaration using the name “sulphites”. This is a declaration threshold, not a guarantee against an individual reaction or permission to add this substance. Schedule 15, compilation F2026C00407 (2026-04-30); Standard 1.3.1, sections 4 and 6 (2024-09-13); Schedule 9, mandatory declarations (2021-02-25). Latest register versions checked . The joint Code applies in Australia and New Zealand; product-specific provisions still matter. |
| New Zealand | Exact permission still unresolved. The selected Schedule 15 rows name sulfur dioxide and sodium/potassium sulfites, not this calcium salt. Their limits cannot be transferred to E227. This scoped check does not establish a blanket ban. Label check: added sulphites at 10 mg/kg or more require a declaration using the name “sulphites”. This is a declaration threshold, not a guarantee against an individual reaction or permission to add this substance. Schedule 15, compilation F2026C00407 (2026-04-30); Standard 1.3.1, sections 4 and 6 (2024-09-13); Schedule 9, mandatory declarations (2021-02-25). Latest register versions checked . The joint Code applies in Australia and New Zealand; product-specific provisions still matter. |
| Japan | Review pending. The relevant list, identity and use standards need an additive-specific check. CAA food-additive lists is a starting source, not a verified permission for this entry. |
Sources & review status
Check what each source covers: an authority’s conclusion, a research finding and a country’s legal permission answer different questions.
What this guide covers
- Selected research
- 3 source summaries, with publication dates and study types. Several publications may describe the same study population.
- Official assessment reference
- EFSA opinion located for E227. Identity and code coverage checked; full findings review pending.
- Original ingredient record
- 1 research link; newest recorded date: . Sources added separately to this guide are not included in this count.
This guide brings together our ingredient record and the dated sources shown here. Missing information describes a gap in this guide; it does not mean an ingredient is untested, safe or harmful. This is not a complete review of every study, preparation or current country rule. The amount in a product and how it is used still matter.
How to read the ratings, research and country checksAgency labels recorded by EatMatrix
These are imported database classifications, not verified current statements from each authority. Use the dated official sources below for their actual scope and conclusions.
| Authority | Database label |
|---|---|
| FDA | Safe |
| WHO | Safe |
| EFSA | Safe |
| FSANZ | Safe |
| Japan | Safe |
| UK FSA | Safe |
| Health Canada | Safe |
An official EFSA assessment for E227
An official scientific opinion covering E227 exists. A missing research link or rating in our database does not mean this additive has never been assessed. This reference identifies the document; it does not replace a review of its findings, later research or current food-use rules.
EFSA: Follow-up of the re-evaluation of sulfur dioxide and sulfites (E220–E224 and E226–E228)
- Published
- Publisher amendment
- Codes covered by this reference
- E220, E221, E222, E223, E224, E226, E227, E228
- Source type
- EFSA scientific opinion, not an individual human trial
The publisher records an erratum correcting exposure calculations following re-analysis of analytical data. Use the amended publisher version rather than an older downloaded copy.
EatMatrix checked this reference’s identity and code coverage on . The full evidence review, an exhaustive check for subsequent publications and corrections, and market-specific permissions remain pending. This does not change the recorded EatMatrix rating above.
Database updated: . What does an E number mean on a food label?
Common questions
Frequently asked questions
What is EatMatrix's recorded rating for E227?
The recorded EatMatrix rating for E227 (Calcium hydrogen sulfite) is “Safe”. It is calculated from labels stored in our ingredient database. These labels are not verified current regulator decisions or country permissions. A database update date is not a scientific review date.
Is E227 vegan, halal or gluten-free?
According to our ingredient data for Calcium hydrogen sulfite — vegan: yes, vegetarian: yes, halal: yes, kosher: yes, gluten-free: yes, dairy-free: yes. Manufacturing sources can vary between products; check the label if it matters to you.
What is E227 and why is it used?
Calcium hydrogen sulfite (chemical formula Ca(HSO3)2) is a sulfite preservative used in winemaking, fruit juices, and pickled vegetables to slow oxidation and microbial spoilage. It releases sulfur dioxide (SO2), which acts as the active antimicrobial and antioxidant component. It's separately used in the paper industry to help break down wood pulp, but that is not a food application. Food use is regulated, and sulfite-sensitive individuals, including some people with asthma, may experience allergic-type reactions.
Does E227 contain allergens?
No known allergens are recorded for Calcium hydrogen sulfite, with a caution: sulfites.
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This page shows information and classifications recorded in our ingredient database. Current scientific and market-specific verification remains pending as described above. It is general information, not medical advice.