Sodium ascorbate
The sodium salt of vitamin C, used to stop fats and colours going stale in processed foods and to preserve colour in cured meats.
What is it?
Sodium ascorbate is the sodium salt of ascorbic acid (vitamin C). It is a white or yellowish crystalline powder that dissolves more readily in water than ascorbic acid itself, making it practical for industrial food processing. The body treats it as a vitamin C source once the sodium and ascorbate ions separate.
What does it do?
It works as an antioxidant by donating electrons to free radicals and reactive oxygen species that would otherwise oxidise fats, pigments and flavour compounds. In cured meats it also accelerates the conversion of nitrite to nitric oxide, which locks in the pink myoglobin colour and reduces residual nitrite levels in the finished product. It can also act as an acidity regulator.
Where you will see it
Most commonly found in cured and processed meats such as bacon, ham, sausages and cooked pork products. Also used in tinned and jarred vegetables and fruit, fruit juices and drinks, breakfast cereals, and some snack foods where fat oxidation would cause rancidity or colour loss. On a UK label it appears as 'sodium ascorbate' or 'E301'.
What the science says
Vitamin C source
Once absorbed, the body uses sodium ascorbate identically to vitamin C from food. At the amounts present in food additives, it contributes a small but genuine amount of ascorbate to dietary intake. There is no evidence of harm from this source at normal food intake levels.
Sodium ascorbate is bioequivalent to ascorbic acid in humans: plasma ascorbate levels rise comparably after ingestion of either form.
High-dose sodium considerations
Sodium ascorbate contributes sodium (approximately 131mg of sodium per gram of the compound). At the concentrations used as a food additive this is negligible compared with dietary sodium from salt. As a supplement taken in gram quantities it can contribute meaningfully to sodium intake, which is relevant for people managing high blood pressure, but this is not a realistic concern from food additive use.
UK dietary guidelines recommend limiting total sodium intake to reduce cardiovascular risk; additive-level sodium ascorbate contributes trivially to total sodium compared with salt added in cooking and processing.
Interaction with nitrites in cured meats
In bacon, ham and similar products, sodium ascorbate is added alongside nitrite preservatives. It accelerates the reaction that produces the cured colour and lowers residual nitrite. This is a deliberate and well-understood process. The concern in cured meats centres on nitrosamines from nitrites, not on the ascorbate itself. Ascorbate actually inhibits nitrosamine formation, so its presence is considered a net positive from a processed-meat chemistry standpoint.
Ascorbate and its salts inhibit N-nitrosamine formation from nitrite in cured meat by competing for available nitrous acid.
Processed meat consumption is classified as a Group 1 carcinogen (sufficient evidence in humans for colorectal cancer). The driver is nitrite chemistry and haem iron, not ascorbate.
Where it stands with the regulators
Who should be careful
People on sodium-restricted diets who are also consuming sodium ascorbate as a high-dose supplement (not from food additive use) should account for its sodium content. At food additive levels, no specific group needs to avoid it. Look for 'sodium ascorbate' or 'E301' on the label.
The honest read
Sodium ascorbate is one of the most ordinary additives on a food label. It is a form of vitamin C, a nutrient the body requires, and has been used in food processing for decades under extensive regulatory scrutiny. The only technical complexity is its role in cured meats alongside nitrites, where it actually reduces nitrosamine formation rather than adding to it. The concern with bacon and ham is the nitrite and haem iron chemistry, not the ascorbate. EFSA and JECFA found no basis for a numerical intake limit. The science here is not live or contested.
Related additives
Common questions
Is E301 banned in the UK?
No. Sodium ascorbate is on the UK FSA approved-additives list and is authorised under assimilated EU Regulation 1333/2008. It is permitted in a wide range of food categories.
Is sodium ascorbate the same as vitamin C?
It is the sodium salt of ascorbic acid (vitamin C). Once absorbed, the body uses the ascorbate identically to vitamin C from food or supplements. It is not chemically identical to ascorbic acid but is bioequivalent as a vitamin C source.
What foods contain E301?
It is most commonly found in cured and processed meats such as bacon, ham and sausages, where it helps maintain colour and reduces residual nitrite. It also appears in tinned vegetables, fruit juices, breakfast cereals and some snack foods.
Is E301 vegan?
Yes. Sodium ascorbate is produced synthetically from glucose via the Reichstein process or microbial fermentation. It does not involve any animal-derived ingredients.
Sources
- UK FSA: Approved additives and E numbers - E301
- EU Regulation 1333/2008 on food additives (assimilated UK version)
- IARC Monograph 114: Consumption of red meat and processed meat
- Mirvish SS: Blocking the formation of N-nitroso compounds with ascorbic acid in vitro and in vivo, Journal of the National Cancer Institute
- Naidu KA: Vitamin C in human health and disease is still a mystery, Nutrition Journal
- SACN: Sodium and Health
Aaron Keen is the founder of NutraSafe. He researches and writes every additive entry himself, from the primary sources. About the research →
This is a guide, not medical advice. If an additive affects you, speak to your GP or a dietitian.
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