Calcium sorbate
A preservative used to stop mould and yeast growing in food. No longer permitted in the UK or EU since 2018 after a safety review could not be completed.
Regulators removed it because no manufacturer provided the genotoxicity studies needed to confirm it does not damage DNA. The data gap was never filled, so safety remains unconfirmed. A closely related compound, sodium sorbate, returned positive genotoxicity signals in laboratory tests on human cells.
What is it?
Calcium sorbate is the calcium salt of sorbic acid, a naturally occurring unsaturated fatty acid first found in mountain-ash berries. It carries the same active preservative component as sorbic acid (E200) and potassium sorbate (E202), bound to a calcium ion. It was a white or off-white powder added to food at low concentrations.
What does it do?
Sorbates work by disrupting the ability of mould, yeast, and some bacteria to grow. Sorbic acid interferes with cellular respiration in fungal cells, generates reactive oxygen species, and damages mitochondrial function, stopping growth rather than killing cells outright. The preservative effect is strongest in acidic conditions below pH 6.5. Calcium sorbate releases sorbic acid once in food, providing the same antimicrobial effect.
Where you will see it
Before its removal from the EU and UK approved list in 2018, calcium sorbate was used in dairy products including cheese and fermented milks, rye bread, dried fruit, confectionery, margarine, soft drinks, processed cheese spreads, frozen pizzas, fruit salads, soup concentrates, and yoghurt. It no longer appears legally on UK or EU food labels. On a pre-2018 label it would have been listed as calcium sorbate or E203.
What the science says
Why it was removed: the genotoxicity data gap
In its 2015 re-evaluation, the EFSA panel reviewed safety data for all three sorbate food additives. It found no genotoxicity concerns for sorbic acid (E200) or potassium sorbate (E202), but concluded it could not include calcium sorbate in the group acceptable daily intake because there was no genotoxicity data specific to this compound. The Commission issued a public call for those studies in 2016. No manufacturer came forward with the data. With the safety assessment impossible to complete, the EU deleted E203 from the approved list in January 2018.
EFSA's ANS Panel concluded that calcium sorbate must be excluded from the group ADI established for sorbic acid and potassium sorbate, because genotoxicity data specific to calcium sorbate were absent.
No business operator submitted the requested genotoxicity studies following the European Commission's 2016 public call for data. The Commission then deleted E203 from the approved food additive list via Regulation (EU) 2018/98, effective 12 August 2018.
Positive genotoxicity signals in a related sorbate compound
The EFSA panel's concern about the data gap was sharpened by the existence of positive genotoxicity signals from sodium sorbate, a structurally related compound that was never authorised as a food additive in the EU. Laboratory studies on human white blood cells showed that sodium sorbate increased chromosome aberrations, sister-chromatid exchanges, and DNA strand breaks at tested concentrations. These are signals that the compound can damage genetic material under laboratory conditions, though the relevance to food-level exposures is not established. EFSA cited this data as a reason why specific genotoxicity studies on calcium sorbate were essential before it could remain approved.
Sodium sorbate increased chromosome aberrations and sister-chromatid exchanges in cultured human lymphocytes at concentrations of 200, 400, and 800 micrograms per millilitre, and caused DNA strand breaks at all tested concentrations.
EFSA cited the available positive genotoxicity data on sodium sorbate as a specific reason why calcium sorbate required dedicated genotoxicity studies before it could be included in the group ADI.
Approved sorbates as context: the group ADI
For comparison, sorbic acid (E200) and potassium sorbate (E202) remain approved in the UK and EU. A 2019 EFSA follow-up opinion reviewed a further reproductive toxicity study for those two compounds and maintained a group ADI of 11 milligrams per kilogram of body weight per day. Calcium sorbate was not reconsidered in that opinion as it had already been removed from the approved list. The approved sorbates are structurally similar to E203, which illustrates that the issue with E203 was the missing proof, not a proven difference in toxicity.
The EFSA FAF Panel maintained a group ADI of 11 mg/kg body weight per day for sorbic acid and potassium sorbate following review of extended one-generation reproductive toxicity data. Calcium sorbate was excluded from this assessment as it had been deauthorised.
Where it stands with the regulators
Who should be careful
Any consumer in the UK or EU should not encounter E203 in legally marketed food. If E203 or calcium sorbate appears on a label of a current UK product, that product is not compliant with UK food additive law. Consumers purchasing imported products from outside the EU and UK, particularly from the US, may still encounter it. Look for calcium sorbate or E203 on ingredient labels.
The honest read
The removal of E203 was not triggered by a proven harm. EFSA and EU regulators applied a precautionary approach: because the genotoxicity question could not be answered without data that manufacturers declined to provide, the additive could not lawfully remain on the approved list. The closely related sorbates, E200 and E202, passed the same scrutiny and remain in wide use. What is honest to say is that the EU regulatory process identified a specific data gap, asked for it to be filled, received no answer, and acted accordingly. Whether calcium sorbate would have passed had studies been conducted is genuinely unknown. That uncertainty, not a verdict of harm, is the accurate state of the science.
Related additives
Common questions
Is E203 banned in the UK?
Yes. Calcium sorbate (E203) was removed from the EU approved food additive list in January 2018 via Commission Regulation (EU) 2018/98, effective 12 August 2018. The UK incorporated this deletion into domestic law before Brexit was completed. It does not appear on the UK FSA approved-additives list. Using it in food sold in the UK is not permitted.
Why was E203 removed if it was not proven harmful?
EU food additive law requires that regulators be able to confirm an additive's safety, not merely the absence of proof of harm. EFSA's 2015 re-evaluation identified a complete absence of genotoxicity data specific to calcium sorbate, and noted that a related compound, sodium sorbate, had returned positive signals in genotoxicity tests. The Commission asked manufacturers to supply the missing studies. None did. Without those studies EFSA could not confirm safety, so the additive was deleted from the approved list. The trigger was an unfilled data gap, not a positive finding of harm.
What foods contained E203?
Before it was deauthorised in 2018, calcium sorbate was used in cheese, fermented milks, rye bread, dried fruit including apricots, confectionery, margarine, soft drinks, processed cheese spreads and slices, frozen pizzas, fruit salads, yoghurt, and soup concentrates. It no longer appears in legally marketed UK or EU food products.
Is E203 vegan?
Yes. Calcium sorbate is produced synthetically and does not involve any animal-derived ingredients or processing. It is suitable for vegans and vegetarians on those grounds. However, as it is not permitted in UK or EU food, the vegan question is mainly relevant to products from countries where it remains authorised, such as the United States.
Sources
- Commission Regulation (EU) 2018/98 of 22 January 2018 amending Annexes II and III to Regulation (EC) No 1333/2008 as regards calcium sorbate (E203)
- EFSA ANS Panel, Scientific Opinion on the re-evaluation of sorbic acid (E200), potassium sorbate (E202) and calcium sorbate (E203) as food additives, EFSA Journal 13(6):4144
- EFSA FAF Panel, Opinion on the follow-up of the re-evaluation of sorbic acid (E200) and potassium sorbate (E202), EFSA Journal 17(2):5625 (PMC7009143)
- Genotoxicity of food preservative sodium sorbate in human lymphocytes in vitro, Food and Chemical Toxicology (PubMed 22373823)
- Calcium sorbate to be banned in EU, FoodNavigator, November 2017
- Deletion of an additive from the EU list as part of the safety re-evaluation process, EU Specialty Food Ingredients
- UK FSA Approved additives and E numbers
- The Preservative Sorbic Acid Targets Respiration, mSphere, ASM
See this on every food you scan
NutraSafe reads the label and puts every additive into plain English, with the source, right in the app.
Get NutraSafe on the App Store