Ascorbyl palmitate

E number E304INS 304CAS 137-66-6

Used as an antioxidant.

Ascorbyl palmitate is a fat-soluble form of vitamin C, used to stop oils and fatty foods going rancid where ordinary ascorbic acid would not dissolve.

Where it is and isn’t permitted

Status of Ascorbyl palmitate by jurisdiction. Every jurisdiction this site covers is listed, including those where the substance does not appear.
JurisdictionStatusScope and limitsCitation
United StatesFood and Drug AdministrationPermitted21 CFR 182.3149retrieved 2026-09-07
Codex AlimentariusCodex Alimentarius Commission / JECFAPermitted, with conditions

46 food categories

highest permitted level 5,000 mg/kg

Show every food category
  • 01.3.2 Beverage whiteners — 80 mg/kg
  • 01.5.1 Milk powder and cream powder (plain) — 500 mg/kg
  • 01.5.2 Milk and cream powder analogues — 80 mg/kg
  • 01.6.1 Unripened cheese — 500 mg/kg
  • 01.6.2.1 Ripened cheese, includes rind — 500 mg/kg
  • 01.7 Dairy-based desserts (e.g. pudding, fruit or flavoured yoghurt) — 500 mg/kg
  • 02.1.1 Butter oil, anhydrous milkfat, ghee — 500 mg/kg
  • 02.1.2 Vegetable oils and fats — 500 mg/kg
  • 02.1.3 Lard, tallow, fish oil, and other animal fats — 500 mg/kg
  • 02.2.2 Fat spreads, dairy fat spreads and blended spreads — 500 mg/kg
  • 02.3 Fat emulsions mainly of type oil-in-water, including mixed and/or flavoured products based on fat emulsions — 500 mg/kg
  • 02.4 Fat-based desserts excluding dairy-based dessert products of food category 01.7 — 80 mg/kg
  • 03.0 Edible ices, including sherbet and sorbet — 200 mg/kg
  • 04.1.2.2 Dried fruit — 80 mg/kg
  • 04.1.2.9 Fruit-based desserts, incl. fruit-flavoured water-based desserts — 500 mg/kg
  • 04.2.2.2 Dried vegetables (including mushrooms and fungi, roots and tubers, pulses and legumes, and aloe vera), seaweeds, and nuts and seeds — 80 mg/kg
  • 05.0 Confectionery — 500 mg/kg
  • 06.3 Breakfast cereals, including rolled oats — 200 mg/kg
  • 06.4.3 Pre-cooked pastas and noodles and like products — 500 mg/kg
  • 06.5 Cereal and starch based desserts (e.g. rice pudding, tapioca pudding) — 500 mg/kg
  • 06.8.1 Soybean-based beverages — 500 mg/kg
  • 07.0 Bakery wares — 1,000 mg/kg
  • 08.4 Edible casings (e.g. sausage casings) — 5,000 mg/kg
  • 09.2.1 Frozen fish, fish fillets, and fish products, including molluscs, crustaceans, and echinoderms — 1,000 mg/kg
  • 09.2.2 Frozen battered fish, fish fillets and fish products, including molluscs, crustaceans, and echinoderms — 1,000 mg/kg
  • 10.4 Egg-based desserts (e.g. custard) — 500 mg/kg
  • 11.4 Other sugars and syrups (e.g. xylose, maple syrup, sugar toppings) — 200 mg/kg
  • 12.2 Herbs, spices, seasonings, and condiments (e.g. seasoning for instant noodles) — 500 mg/kg
  • 12.4 Mustards — 500 mg/kg
  • 12.5 Soups and broths — 200 mg/kg
  • 12.6.1 Emulsified sauces and dips (e.g. mayonnaise, salad dressing, onion dips) — 500 mg/kg
  • 12.6.2 Non-emulsified sauces (e.g. ketchup, cheese sauce, cream sauce, brown gravy) — 500 mg/kg
  • 12.6.3 Mixes for sauces and gravies — 200 mg/kg
  • 12.6.4 Clear sauces (e.g. fish sauce) — 200 mg/kg
  • 12.7 Salads (e.g. macaroni salad, potato salad) and sandwich spreads excluding cocoa-and nut-based spreads of food categories 04.2.2.5 and 05.1.3 — 200 mg/kg
  • 13.1.1 Infant formulae — 10 mg/kg
  • 13.1.2 Follow-up formulae — 50 mg/kg
  • 13.1.3 Formulae for special medical purposes for infants — 10 mg/kg
  • 13.2 Complementary foods for infants and young children — 200 mg/kg
  • 13.3 Dietetic foods intended for special medical purposes (excluding products of food category 13.1) — 10 mg/kg
  • 13.4 Dietetic formulae for slimming purposes and weight reduction — 500 mg/kg
  • 13.5 Dietetic foods (e.g. supplementary foods for dietary use) excluding products of food categories — 500 mg/kg
  • 13.6 Food supplements — 500 mg/kg
  • 14.1.4 Water-based flavoured drinks, including "sport," “energy,” or "electrolyte" drinks and particulated drinks — 1,000 mg/kg
  • 15.1 Snacks - potato, cereal, flour or starch based (from roots and tubers, pulses and legumes) — 200 mg/kg
  • 15.2 Processed nuts, including coated nuts and nut mixtures (with e.g. dried fruit) — 200 mg/kg
CXS 192-1995 Table One, INS 304and 45 further provisionsretrieved 2026-09-07

What it is made from

Made by esterifying ascorbic acid with palmitic acid. The ascorbic acid is fermentation-derived; the palmitic acid may come from palm oil or animal fat and is not usually declared.

  • Vegan status depends on the source
  • Vegetarian status depends on the source
  • May raise a halal question
  • May raise a kosher question

This is not an omission. What this additive is made from is not fixed — depending on the manufacturer it may be plant, animal or microbial in origin, nobody is required to say which, and the same product can change source between production runs. Ask the manufacturer if it matters to you; a label cannot answer it.

CAS registry number
137-66-6
InChIKey
QAQJMLQRFWZOBN-LAUBAEHRSA-N
PubChem
CID 54680660

Every name it appears under

72 recorded names. A label may use any of them.

E number

  • E304

INS number

  • 304
  • 305

CAS registry number

  • 137-66-6
  • 51222-59-4

As it appears in regulation

  • Ascorbyl palmitate

Other names

  • (S)-2-((R)-3,4-Dihydroxy-5-oxo-2,5-dihydrofuran-2-yl)-2-hydroxyethyl palmitate
  • 1-Ascorbyl palmitate
  • 1Ascorbyl palmitate
  • 2-(3,4-dihydroxy-5-oxo-2,5-dihydrofuran-2-yl)-2-hydroxyethyl hexadecanoate
  • 5-18-05-00031 (Beilstein Handbook Reference)
  • 6-Hexadecanoyl-L-ascorbic acid
  • 6-Monopalmitoyl-L-ascorbate
  • 6-O-Palmitoyl ascorbate
  • 6-O-Palmitoyl-L-ascorbic acid
  • 6-O-palmitoylascorbic acid
  • 6-Palmitoyl-L-ascorbic acid
  • 6-Palmitoylascorbic acid
  • 6HexadecanoylLascorbic acid
  • 6MonopalmitoylLascorbate
  • 6OPalmitoyl ascorbate
  • 6OPalmitoylascorbic acid
  • 6Palmitoylascorbic acid
  • 6PalmitoylLascorbic acid
  • Ascorbic acid palmitate
  • Ascorbic acid palmitate (ester)
  • Ascorbic palmitate
  • Ascorboyl palmitate
  • ascorbyl
  • Ascorbyl 6-hexadecanoate, L-
  • Ascorbyl 6-palmitate
  • Ascorbyl 6hexadecanoate, L
  • Ascorbyl 6palmitate
  • ASCORBYL ESTERS
  • Ascorbyl monopalmitate
  • Ascorbyl palmitate
  • ASCORBYL PALMITATE (EP MONOGRAPH)
  • ASCORBYL PALMITATE (II)
  • ASCORBYL PALMITATE (MART.)
  • Ascorbyl palmitate (NF)
  • ASCORBYL PALMITATE (USP-RS)
  • Ascorbyl palmitate (VAN)
  • Ascorbyl palmitate, USAN
  • Ascorbyl palmitic acid
  • Ascorbyl stearate
  • Ascorbylpalmitic acid
  • BRN 0096552
  • CCRIS 3930
  • Cetyl ascorbate
  • E 304(i)
  • E 304(ii)
  • HSDB 418
  • Ins no.304
  • Ins-304
  • L-Ascorbic acid 6-palmitate
  • L-Ascorbic acid, 6-hexadecanoate
  • L-Ascorbyl 6-palmitate
  • L-Ascorbyl monopalmitate
  • L-ascorbyl palmitate
  • LAscorbic acid 6palmitate
  • LAscorbic acid, 6hexadecanoate
  • LAscorbyl 6palmitate
  • LAscorbyl monopalmitate
  • LAscorbyl palmitate
  • Ondascora
  • Palmitic acid, ester with ascorbic acid
  • Palmitoyl L-ascorbic acid
  • Palmitoyl Lascorbic acid
  • Palmitoyl-L-ascorbic acid
  • Quicifal

Systematic names

  • [(2S)-2-[(2R)-3,4-dihydroxy-5-oxo-2H-furan-2-yl]-2-hydroxyethyl] hexadecanoate
  • octadecanoic acid--hex-1-enofuranos-3-ulose (1/1)

Hazard reference values

No reference value for this substance in the sources we hold.

Evidence and how bodies read it

Studies, and the differing conclusions regulators drew from them, are curated by hand rather than machine-read, and none has been written for this substance yet.

Sources for this page

  • ecfr retrieved 2026-09-07
  • gsfa retrieved 2026-09-07

Full licence terms and publisher details on Sources. How this page is built and updated: Method.

Machine-readable:/api/v1/additives/ascorbyl-palmitate.json