What is E317?
Complete guide to understanding E317 (Potassium Ascorbate) — a vitamin C salt with limited global availability
The Quick Answer
E317 (Potassium Ascorbate) is a potassium salt of vitamin C that acts both as an antioxidant preservative AND as a nutritional source of vitamin C and potassium.
Unlike E315 (erythorbic acid) and E316 (sodium erythorbate), which have virtually no vitamin activity, E317 is actual vitamin C with full nutritional benefits.
It’s extremely safe, approved by EFSA for animal feed, and permitted in Australia and New Zealand — but NOT allowed in the US, EU, or UK as a food additive due to regulatory classification, not safety concerns.
📌 Quick Facts
- Chemical Name: Potassium Salt of Ascorbic Acid (Potassium Ascorbate)
- Other Designations: E317 or E303 (designation varies by source)
- Type: Vitamin C salt; antioxidant with full nutritional activity
- Found in: Australia, New Zealand (food); most countries (dietary supplements)
- Safety Status: Extremely safe; approved as animal feed additive (EFSA 2025)
- Approved by: Australia/NZ (food); EFSA (animal feed); globally as supplement
- NOT permitted in: US, EU, UK as food additive (regulatory, not safety-based)
- Key difference: REAL vitamin C (100% activity) plus potassium; unlike E315/E316 (no vitamin activity)
What Exactly Is It?
E317 is a white crystalline powder — the potassium salt of ascorbic acid (vitamin C), created by combining vitamin C with potassium.
Critical distinction: This is NOT the same as E315 or E316:
| Additive | Chemical Form | Vitamin C Activity | Mineral Contribution | Nutritional Value |
|---|---|---|---|---|
| E317 (Potassium Ascorbate) | Potassium salt of vitamin C | 100% (Full activity) | Potassium | Nutritious; provides vitamin C + mineral |
| E315 (Erythorbic Acid) | Synthetic isomer of vitamin C | ~0.03% (Essentially none) | None | Food preservative only; not nutritious |
| E316 (Sodium Erythorbate) | Sodium salt of erythorbic acid | ~0.03% (Essentially none) | Sodium | Food preservative only; not nutritious |
| E301 (Sodium Ascorbate) | Sodium salt of vitamin C | 100% (Full activity) | Sodium | Nutritious; globally approved as food additive |
Production method: E317 is created through fermentation of glucose using microorganisms, forming ascorbic acid, then neutralizing it with potassium to create the potassium salt form.
Where You’ll Find It (Geographic Variation)
Permitted for Food Use
Very limited global availability:
| Region | Status | Applications |
|---|---|---|
| Australia | Approved (E317) | Various food categories; meat products, beverages, baked goods |
| New Zealand | Approved (E317) | Similar to Australia |
| Japan | May be approved in some applications | Limited use; varies by specific product category |
NOT Permitted for Food Use
– United States: NOT permitted as food additive (classified as nutrient/supplement form)
– European Union: NOT permitted as food additive (similar regulatory classification)
– United Kingdom: NOT permitted as food additive
– Canada: Status unclear; likely restricted
Why the ban in US/EU/UK? Not due to safety concerns, but because vitamin C and its salts are classified as nutrients or therapeutic agents, not traditional food additives. Different regulatory frameworks handle nutrient fortification versus additive use differently.
Available as Dietary Supplement Globally
E317 is widely available and approved worldwide as a dietary supplement in capsule, powder, and liquid forms — separate from the food additive classification.
Why This Regulatory Difference?
The US/EU/UK approach: “Vitamin C and salts are nutrients, not food additives. Use them for fortification purposes through supplement regulations, not food additive regulations.”
The Australia/NZ approach: “Allow nutrient-form additives in the food additive framework; more permissive and practical for manufacturers.”
Neither approach is based on safety: EFSA recently approved potassium ascorbate (E317) as an animal feed additive (2025), confirming it’s deemed extremely safe for all animal species. The food ban is purely regulatory/jurisdictional, not toxicological.
Why Would You Use E317 Instead of Other Vitamin C Forms?
E317 offers advantages over regular ascorbic acid:
1. Less acidic: Better tolerated by stomach than ascorbic acid
2. Buffered form: Doesn’t affect tooth enamel like ascorbic acid
3. Potassium bonus: Provides both vitamin C AND mineral potassium
4. Higher solubility: Dissolves better in water than ascorbic acid
5. Better for beverages: Clear solutions without flavor impact
6. Electrolyte balance: Potassium helps maintain cellular function
Is It Safe?
The Official Position
E317 is considered extremely safe by regulatory agencies worldwide.
Safety assessments:
| Authority | Finding | Basis |
|---|---|---|
| EFSA (2025) | Approved as animal feed additive; safe for all species | Comprehensive safety review |
| EFSA (vitamin C basis) | Ascorbic acid and salts very safe | Extensive human & animal data |
| FDA/Health Canada | Safe at permitted levels (where approved) | Standard safety assessment |
| Global consensus | Among safest food additives known | Decades of safety data |
Toxicity Profile
| Safety Criterion | Finding | Assessment |
|---|---|---|
| Acute toxicity | Very low; no adverse effects at normal doses | Safe to consume |
| Chronic toxicity | Extensively studied; no concerns | Safe for long-term exposure |
| Genotoxicity | No DNA damage concern | Not genotoxic |
| Carcinogenicity | No cancer risk identified | Not carcinogenic |
| Allergies | Rare; may occur in hypersensitive individuals | Generally well-tolerated |
| Gastrointestinal | Large doses (>2000 mg/day) may cause loose stools (osmotic effect) | Normal doses safe |
Recommended Intake Limits
Vitamin C component:
– Tolerable Upper Intake Level: 2000 mg/day (from all sources)
– Recommended Dietary Allowance: 75-90 mg/day for adults
– Typical food use: Minimal, well below limits
Potassium component:
– E317 contains ~175 mg potassium per gram
– Maximum recommended: 3500 mg/day (all sources)
– Food use: Minimal contribution to overall intake
Cautions for Specific Groups
People who should limit intake:
– Those with kidney disease or renal insufficiency (potassium concern)
– People taking potassium-sparing diuretics
– Individuals with hemochromatosis (iron overload)
– Those with G6PD deficiency (glucose-6-phosphate dehydrogenase)
High-dose vitamin C risks (generally not applicable to food use):
– Kidney stone formation in susceptible individuals (very high doses: >2000 mg/day)
– Gastrointestinal upset at excessive intakes
– Potential increased stroke risk if supplementing with extreme amounts (research ongoing)
Natural vs. Synthetic
E317 is fermentation-derived but processed into salt form, making it semi-synthetic:
– Produced through bacterial fermentation of glucose (renewable, natural process)
– Then chemically neutralized with potassium to create salt form
– Unlike purely synthetic E315/E316, E317 is actual vitamin C (naturally occurring compound)
– More “natural” than E315/E316 because it provides a recognized nutrient
The Bottom Line
E317 (Potassium Ascorbate) is an extremely safe vitamin C salt that provides both antioxidant function and nutritional vitamin C activity.
What you should know:
- It’s very safe: EFSA approved as animal feed additive; safe by all measures
- It’s nutritious: Real vitamin C (100% activity) plus potassium mineral
- It’s geographically limited: Only approved for food in Australia/NZ; banned in US/EU/UK (regulatory, not safety-based)
- It’s available globally as a supplement: Widely sold in dietary supplement form
- It’s different from E315/E316: Has full vitamin C activity, unlike those synthetic alternatives
- It’s less acidic: Better tolerated by stomach and teeth than ascorbic acid
- It has dual benefits: Antioxidant preservation AND nutritional supplementation
- It’s affordable and stable: Practical for food and supplement manufacturers