Sodium sesquicarbonate

INS 500(iii)CAS 533-96-0

Listed as an acidity regulator by Codex and the US.

Listed as acidity regulators (US, Codex) · thickeners (Codex) · raising agents (Codex) · stabilisers (Codex) · anticaking agents (Codex)
Chemical structure of Sodium sesquicarbonate, from PubChem compound 10791
Structure from PubChem CID 10791 (National Library of Medicine, public domain). A depiction of one compound: where a listing covers a family, or a substance has no single structure, this page shows none.

Sodium sesquicarbonate is an alkali used to adjust acidity, midway in strength between bicarbonate of soda and washing soda.

Where it is and isn’t permitted

Status of Sodium sesquicarbonate by jurisdiction. Every jurisdiction this site covers is listed, including those where the substance does not appear.
JurisdictionStatusScope and limitsCitation
Australia and New ZealandFood Standards Australia New ZealandNo listed food uses foundThis site has not matched this substance to any food use on this jurisdiction’s list of authorised food additives. A food additive may be used only in foods that list names. Flavourings, enzymes, processing aids and added nutrients are regulated separately and do not appear on it.Related listings with permitted uses here: Sodium bicarbonate (E500), Sodium carbonate (E500). This site cannot tell whether those listings cover this exact form.
CanadaHealth CanadaNo listing matchedHealth Canada’s lists name additives without E or INS numbers, so this site matches them by exact name. A substance listed there under a name this site does not recognise has no row here.Related listings with permitted uses here: Sodium bicarbonate (E500), Sodium carbonate (E500). This site cannot tell whether those listings cover this exact form.
European UnionEuropean Commission / EFSAPermitted, with conditions

81 food categories

highest permitted level 70,000 mg/l

Show every food category
  • 1.10 Milk-based drinks and similar products intended for young children* — quantum satisAuthorised under E 500, Sodium carbonates. quantum satis.
  • 1.3 unflavoured fermented milk products heat-treated after fermentation — several limitsAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I, Additives. ML = quantum satis; except E 425 ML = 10000 mg/kg; E 620 to E 625, ML = 10000 mg/kg individually or in combination, expressed as glutamic acid; E 626 to E 635, ML = 500 mg/kg individually or in combination, expressed as guanylic acid.
  • 1.4 flavoured fermented milk products including heat-treated products — several limitsAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I, Additives. ML = quantum satis; except E 425 ML = 10000 mg/kg; E 620 to E 625, ML = 10000 mg/kg individually or in combination, expressed as glutamic acid; E 626 to E 635, ML = 500 mg/kg individually or in combination, expressed as guanylic acid.
  • 1.6.3 other creams — several limitsAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I, Additives. ML = quantum satis; except E 425 ML = 10000 mg/kg; E 620 to E 625, ML = 10000 mg/kg individually or in combination, expressed as glutamic acid; E 626 to E 635, ML = 500 mg/kg individually or in combination, expressed as guanylic acid.
  • 1.7.1 unripened cheese excluding products falling in category 16Authorised under E 500, Sodium carbonates. Permitted as a member of Group I, Additives. except mozzarella.
  • 1.7.5 processed cheese — several limitsAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I, Additives. except E 425 ML = 10000 mg/kg; E 620 to E 625, ML =10000 mg/kg individually or in combination, expressed as glutamic acid;E 626 to E 635, ML = 500 mg/kg individually or in combination, expressedas guanylic acid.
  • 1.7.6 cheese products (excluding products falling in category 16) — several limitsAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I, Additives. ML = quantum satis; except E 425 ML = 10000 mg/kg; E 620 to E 625, ML = 10000 mg/kg individually or in combination, expressed as glutamic acid; E 626 to E 635, ML = 500 mg/kg individually or in combination, expressed as guanylic acid.
  • 1.8 Dairy analogues, including beverage whiteners — several limitsAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I, Additives. ML = quantum satis; except E 425 ML = 10000 mg/kg; E 620 to E 625, ML = 10000 mg/kg individually or in combination, expressed as glutamic acid; E 626 to E 635, ML = 500 mg/kg individually or in combination, expressed as guanylic acid.
  • 1.9 Edible caseinates — quantum satisAuthorised under E 500, Sodium carbonates. quantum satis.
  • 10.2 processed eggs and egg products — several limitsAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I, Additives. ML = quantum satis; except E 425 ML = 10000 mg/kg; E 620 to E 625, ML =10000 mg/kg individually or in combination, expressed as glutamic acid;E 626 to E 635, ML = 500 mg/kg individually or in combination, expressedas guanylic acid.
  • 11.2 Other sugars and syrups — several limitsAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I, Additives. ML = quantum satis; except E 425 ML = 10000 mg/kg; E 620 to E 625, ML = 10000 mg/kg individually or in combination, expressed as glutamic acid; E 626 to E 635, ML = 500 mg/kg individually or in combination, expressed as guanylic acid.
  • 11.4.1 table-top sweeteners in liquid form — quantum satisAuthorised under E 500, Sodium carbonates. quantum satis.
  • 11.4.2 table-top sweeteners in powder form — quantum satisAuthorised under E 500, Sodium carbonates. quantum satis.
  • 11.4.3 table-top sweeteners in tablets — quantum satisAuthorised under E 500, Sodium carbonates. quantum satis.
  • 12.1.1 Salt — quantum satisAuthorised under E 500, Sodium carbonates. quantum satis.
  • 12.1.2 salt substitutes — several limitsAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I, Additives. ML = quantum satis; except E 425 ML = 10000 mg/kg; E 620 to E 625, ML = 10000 mg/kg individually or in combination, expressed as glutamic acid; E 626 to E 635, ML = 500 mg/kg individually or in combination, expressed as guanylic acid.
  • 12.2.2 Seasonings and condiments — several limitsAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I, Additives. ML = quantum satis; except E 425 ML = 10000 mg/kg; E 620 to E 625, ML = 10000 mg/kg individually or in combination, expressed as glutamic acid; E 626 to E 635, ML = 500 mg/kg individually or in combination, expressed as guanylic acid.
  • 12.3 Vinegars and diluted acetic acid (diluted with water to 4-30 % by volume) — several limitsAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I, Additives. ML = quantum satis; except E 425 ML = 10000 mg/kg; E 620 to E 625, ML = 10000 mg/kg individually or in combination, expressed as glutamic acid; E 626 to E 635, ML = 500 mg/kg individually or in combination, expressed as guanylic acid.
  • 12.4 Mustard — several limitsAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I, Additives. ML = quantum satis; except E 425 ML = 10000 mg/kg; E 620 to E 625, ML = 10000 mg/kg individually or in combination, expressed as glutamic acid; E 626 to E 635, ML = 500 mg/kg individually or in combination, expressed as guanylic acid.
  • 12.5 Soups and broths — several limitsAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I, Additives. ML = quantum satis; except E 425 ML = 10000 mg/kg; E 620 to E 625, ML = 10000 mg/kg individually or in combination, expressed as glutamic acid; E 626 to E 635, ML = 500 mg/kg individually or in combination, expressed as guanylic acid.
  • 12.6 Sauces — several limitsAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I, Additives. ML = quantum satis; except E 425 ML = 10000 mg/kg; E 620 to E 625, ML = 10000 mg/kg individually or in combination, expressed as glutamic acid; E 626 to E 635, ML = 500 mg/kg individually or in combination, expressed as guanylic acid.
  • 12.7 Salads and savoury-based sandwich spreads — several limitsAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I, Additives. ML = quantum satis; except E 425 ML = 10000 mg/kg; E 620 to E 625, ML = 10000 mg/kg individually or in combination, expressed as glutamic acid; E 626 to E 635, ML = 500 mg/kg individually or in combination, expressed as guanylic acid.
  • 12.8 Yeast and yeast products — several limitsAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I, Additives. ML = quantum satis; except E 425 ML = 10000 mg/kg; E 620 to E 625, ML = 10000 mg/kg individually or in combination, expressed as glutamic acid; E 626 to E 635, ML = 500 mg/kg individually or in combination, expressed as guanylic acid.
  • 12.9 Protein products excluding products covered in category 1 8 — several limitsAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I, Additives. ML = quantum satis; except E 425 ML = 10000 mg/kg; E 620 to E 625, ML = 10000 mg/kg individually or in combination, expressed as glutamic acid; E 626 to E 635, ML = 500 mg/kg individually or in combination, expressed as guanylic acid.
  • 13.1.3 Processed cereal-based foods and baby foods as defined by Regulation (EU) No 609/2013 — quantum satisAuthorised under E 500, Sodium carbonates. quantum satis. only as rising agent.
  • 13.1.5 Foods for special medical purposes, as defined by Regulation (EU) No 609/2013, intended for infants and young children — quantum satisAuthorised under E 500, Sodium carbonates. quantum satis. only as rising agent.
  • 13.1.5.1 Foods for special medical purposes as defined by Regulation (EU) No 609/2013, intended for infants — quantum satisAuthorised under E 500, Sodium carbonates. quantum satis. only as rising agent.
  • 13.2 Foods for special medical purposes as defined by Regulation (EU) No 609/2013 (excluding products from food category 13.1.5.) — several limitsAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I, Additives. ML = quantum satis; except E 425 ML = 10000 mg/kg; E 620 to E 625, ML = 10000 mg/kg individually or in combination, expressed as glutamic acid; E 626 to E 635, ML = 500 mg/kg individually or in combination, expressed as guanylic acid.
  • 13.3 Total diet replacement for weight control food as defined by Regulation (EU) No 609/2013 — several limitsAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I, Additives. ML = quantum satis; except E 425 ML = 10000 mg/kg; E 620 to E 625, ML = 10000 mg/kg individually or in combination, expressed as glutamic acid; E 626 to E 635, ML = 500 mg/kg individually or in combination, expressed as guanylic acid.
  • 14.1.2 Fruit juices as defined by Directive 2001/112/EC and vegetable juicesAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I, Additives. only vegetable juices.
  • 14.1.3 Fruit nectars as defined by Directive 2001/112/EC and vegetable nectars and similar productsAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I, Additives. only vegetable nectars, E 420, E421, E 953, E965, E 966, E 967 and E 968 may not be used.
  • 14.1.4 Flavoured_drinksAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I, Additives. E 420, E 421, E 953, E 965, E 966 and E 967 may not be used E 968 may not be used except where specifically provided for in this food category.
  • 14.1.5.2 otherAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I, Additives. excluding unflavoured leaf tea; including flavoured instant coffee; E 420, E421, E 953, E965, E 966, E 967 and E 968 may not be used in drinks.
  • 14.2.3 Cider and perryAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I, Additives. E 420, E421, E 953, E965, E 966, E 967 and E 968 may not be used.
  • 14.2.4 Fruit wine and made wineAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I, Additives. E 420, E421, E 953, E965, E 966, E 967 and E 968 may not be used.
  • 14.2.5 MeadAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I, Additives. E 420, E421, E 953, E965, E 966, E 967 and E 968 may not be used.
  • 14.2.6 Spirit drinks as defined in Regulation (EU) 2019/787Authorised under E 500, Sodium carbonates. Permitted as a member of Group I, Additives. except whisky or whiskey; E 420, E421, E 953, E 965, E 966, E 967 and E 968 may not be used except in liqueurs.
  • 14.2.7.1 Aromatised winesAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I, Additives. E 420, E421, E 953, E965, E 966, E 967 and E 968 may not be used.
  • 14.2.7.2 Aromatised wine-based drinksAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I, Additives. E 420, E421, E 953, E965, E 966, E 967 and E 968 may not be used.
  • 14.2.7.3 Aromatised wine-product cocktailsAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I, Additives. E 420, E421, E 953, E965, E 966, E 967 and E 968 may not be used.
  • 14.2.8 Other alcoholic beverages including mixtures of alcoholic beverages with non-alcoholic beverages and other alcoholic beverages based on distilled alcohol with alcoholic strength by volume less than 15 %Authorised under E 500, Sodium carbonates. Permitted as a member of Group I, Additives. E 420, E421, E 953, E 965, E 966, E 967 and E 968 may not be used.
  • 15.1 Potato- cereal- flour- or starch-based snacks — several limitsAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I, Additives. ML = quantum satis; except E 425 ML = 10000 mg/kg; E 620 to E 625, ML = 10000 mg/kg individually or in combination, expressed as glutamic acid; E 626 to E 635, ML = 500 mg/kg individually or in combination, expressed as guanylic acid.
  • 15.2 Processed nuts — several limitsAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I, Additives. ML = quantum satis; except E 425 ML = 10000 mg/kg; E 620 to E 625, ML = 10000 mg/kg individually or in combination, expressed as glutamic acid; E 626 to E 635, ML = 500 mg/kg individually or in combination, expressed as guanylic acid.
  • 16 Desserts excluding products covered in category 1 3 and 4 — several limitsAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I, Additives. ML = quantum satis; except E 425 ML = 10000 mg/kg; E 620 to E 625, ML = 10000 mg/kg individually or in combination, expressed as glutamic acid; E 626 to E 635, ML = 500 mg/kg individually or in combination, expressed as guanylic acid.
  • 17.1 food supplements supplied in a solid form excluding food supplements for infants and young children’,Authorised under E 500, Sodium carbonates. Permitted as a member of Group I, Additives. E 410, E 412, E 415, E 417 and E 425 may not be used to produce dehydrated food supplements intended to rehydrate on ingestion.
  • 17.2 food supplements supplied in a liquid form excluding food supplements for Infants and young children — several limitsAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I, Additives. ML = quantum satis; except E 425 ML = 10000 mg/kg; E 620 to E 625, ML = 10000 mg/kg individually or in combination, expressed as glutamic acid; E 626 to E 635, ML = 500 mg/kg individually or in combination, expressed as guanylic acid.
  • 18 Processed foods not covered by categories 1 to 17 — several limitsAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I, Additives. ML = quantum satis; except E 425 ML = 10000 mg/kg; E 620 to E 625, ML = 10000 mg/kg individually or in combination, expressed as glutamic acid; E 626 to E 635, ML = 500 mg/kg individually or in combination, expressed as guanylic acid.
  • 18.1 Processed foods not covered by categories 18.2 and 18.3, excluding foods for infants and young children — several limitsAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I, Additives. ML = quantum satis; except E 425 ML = 10000 mg/kg; E 620 to E 625, ML = 10000 mg/kg individually or in combination, expressed as glutamic acid; E 626 to E 635, ML = 500 mg/kg individually or in combination, expressed as guanylic acid.
  • 18.2 Meal replacement for weight control as referred to in Commission Regulation (EU) No 432/2012 — several limitsAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I, Additives. ML = quantum satis; except E 425 ML = 10000 mg/kg; E 620 to E 625, ML = 10000 mg/kg individually or in combination, expressed as glutamic acid; E 626 to E 635, ML = 500 mg/kg individually or in combination, expressed as guanylic acid.
  • 18.3 Food specially produced to reduce the gluten content of gluten-containing ingredients or substitute the gluten-containing ingredientsAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I, Additives. Including dry pasta.
  • 2.2.1 Butter and concentrated butter and butter oil and anhydrous milk fat — quantum satisAuthorised under E 500, Sodium carbonates. quantum satis. only soured cream butter.
  • 2.2.2 Other fat and oil emulsions including spreads as defined by Regulation (EC) No 1234/2007 and liquid emulsions — several limitsAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I, Additives. ML = quantum satis; except E 425 ML = 10000 mg/kg; E 620 to E 625, ML = 10000 mg/kg individually or in combination, expressed as glutamic acid; E 626 to E 635, ML = 500 mg/kg individually or in combination, expressed as guanylic acid.
  • 2.3 Vegetable oil pan spray — several limitsAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I, Additives. ML = quantum satis; except E 425 ML = 10000 mg/kg; E 620 to E 625, ML = 10000 mg/kg individually or in combination, expressed as glutamic acid; E 626 to E 635, ML = 500 mg/kg individually or in combination, expressed as guanylic acid.
  • 3 edible ices — several limitsAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I, Additives. ML = quantum satis; except E 425 ML = 10000 mg/kg; E 620 to E 625, ML = 10000 mg/kg individually or in combination, expressed as glutamic acid; E 626 to E 635, ML = 500 mg/kg individually or in combination, expressed as guanylic acid.
  • 4.2.1 dried fruit and vegetablesAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I, Additives. E 410, E 412, E 415 and E 417 may not be used to produce dehydrated foods intended to rehydrate on ingestion.
  • 4.2.2 fruit and vegetables in vinegar oil or brine — several limitsAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I, Additives. ML = quantum satis; except E 425 ML = 10000 mg/kg; E 620 to E 625, ML = 10000 mg/kg individually or in combination, expressed as glutamic acid; E 626 to E 635, ML = 500 mg/kg individually or in combination, expressed as guanylic acid.
  • 4.2.4.1 fruit and vegetable preparations excluding compote — several limitsAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I, Additives. ML = quantum satis; except E 425 ML = 10000 mg/kg; E 620 to E 625, ML = 10000 mg/kg individually or in combination, expressed as glutamic acid; E 626 to E 635, ML = 500 mg/kg individually or in combination, expressed as guanylic acid.
  • 4.2.5.4 nut butters and nut spreads — several limitsAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I, Additives. ML = quantum satis; except E 425 ML = 10000 mg/kg; E 620 to E 625, ML = 10000 mg/kg individually or in combination, expressed as glutamic acid; E 626 to E 635, ML = 500 mg/kg individually or in combination, expressed as guanylic acid.
  • 4.2.6 processed potato products — several limitsAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I, Additives. ML = quantum satis; except E 425 ML = 10000 mg/kg; E 620 to E 625, ML = 10000 mg/kg individually or in combination, expressed as glutamic acid; E 626 to E 635, ML = 500 mg/kg individually or in combination, expressed as guanylic acid.
  • 5.1 Cocoa and chocolate products as covered by Directive 2000/36/ECAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I, Additives. only energy-reduced or with no added sugars.
  • 5.1 Cocoa and chocolate products as covered by Directive 2000/36/EC — 70,000 mg/kgAuthorised under E 500, Sodium carbonates. Permitted as a member of Carbonates. ML = 70000 mg/kg. E 170, E 500 - 504, E 524 - 528 and E 530: 7 % on dry matter, without fat, expressed as potassium carbonates.
  • 5.2 Other confectionery including breath freshening micro-sweetsAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I, Additives. The substances listed under numbers E 400, E 401, E 402, E 403, E 404, E 406, E 407, 407a, E 410, E 412, E 413, E 414, E 415, E 417, E 418, E 425 and E 440 may not be used in jelly mini-cups, defined, for the purpose of this Regulation, as jelly confectionery of a firm consistence, contained in semi rigid mini-cups or mini-capsules, intended to be ingested in a single bite by exerting pressure on the mini-cups or mini-capsule to project the confectionery into the mouth; E 410, E 412, E 415 E 417 may not be used to produce dehydrated foods intended to rehydrate on ingestion. E425 may not be used in jelly confectionery.
  • 5.3 chewing gum — several limitsAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I, Additives. ML = quantum satis; except E 425 ML = 10000 mg/kg; E 620 to E 625, ML = 10000 mg/kg individually or in combination, expressed as glutamic acid; E 626 to E 635, ML = 500 mg/kg individually or in combination, expressed as guanylic acid.
  • 5.4 Decorations, coatings and fillings, except fruit-based fillings covered by category 4.2.4 — several limitsAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I, Additives. ML = quantum satis; except E 425 ML = 10000 mg/kg; E 620 to E 625, ML = 10000 mg/kg individually or in combination, expressed as glutamic acid; E 626 to E 635, ML = 500 mg/kg individually or in combination, expressed as guanylic acid.
  • 6.2.2 starches — several limitsAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I, Additives. ML = quantum satis; except E 425 ML = 10000 mg/kg; E 620 to E 625, ML = 10000 mg/kg individually or in combination, expressed as glutamic acid; E 626 to E 635, ML = 500 mg/kg individually or in combination, expressed as guanylic acid.
  • 6.3 breakfast cereals — several limitsAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I, Additives. ML = quantum satis; except E 425 ML = 10000 mg/kg; E 620 to E 625, ML = 10000 mg/kg individually or in combination, expressed as glutamic acid; E 626 to E 635, ML = 500 mg/kg individually or in combination, expressed as guanylic acid.
  • 6.4.2 Dry pasta — several limitsAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I, Additives. ML = quantum satis; except E 425 ML = 10000 mg/kg; E 620 to E 625, ML = 10000 mg/kg individually or in combination, expressed as glutamic acid; E 626 to E 635, ML = 500 mg/kg individually or in combination, expressed as guanylic acid.
  • 6.4.4 Potato GnocchiAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I, Additives. except fresh refrigerated potato gnocchi.
  • 6.4.5 fillings of stuffed pasta (ravioli and similar) — several limitsAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I, Additives. ML = quantum satis; except E 425 ML = 10000 mg/kg; E 620 to E 625, ML = 10000 mg/kg individually or in combination, expressed as glutamic acid; E 626 to E 635, ML = 500 mg/kg individually or in combination, expressed as guanylic acid.
  • 6.5 Noodles — several limitsAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I, Additives. ML = quantum satis; except E 425 ML = 10000 mg/kg; E 620 to E 625, ML = 10000 mg/kg individually or in combination, expressed as glutamic acid; E 626 to E 635, ML = 500 mg/kg individually or in combination, expressed as guanylic acid.
  • 6.6 Batters — several limitsAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I, Additives. ML = quantum satis; except E 425 ML = 10000 mg/kg; E 620 to E 625, ML = 10000 mg/kg individually or in combination, expressed as glutamic acid; E 626 to E 635, ML = 500 mg/kg individually or in combination, expressed as guanylic acid.
  • 6.7 pre-cooked or processed cereals — several limitsAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I, Additives. ML = quantum satis; except E 425 ML = 10000 mg/kg; E 620 to E 625, ML = 10000 mg/kg individually or in combination, expressed as glutamic acid; E 626 to E 635, ML = 500 mg/kg individually or in combination, expressed as guanylic acid.
  • 7.1 Bread and rollsAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I, Additives. except products in 7.1.1 and 7.1.2.
  • 7.2 Fine bakery wares — several limitsAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I, Additives. ML = quantum satis; except E 425 ML = 10000 mg/kg; E 620 to E 625, ML = 10000 mg/kg individually or in combination, expressed as glutamic acid; E 626 to E 635, ML = 500 mg/kg individually or in combination, expressed as guanylic acid.
  • 8.2 Meat preparations as defined by Regulation (EC) No 853/2004 — quantum satisAuthorised under E 500, Sodium carbonates. quantum satis. only poultry meat preparations, mici, bifteki, soutzoukaki, kebap, seftalia, ćevapčići and pljeskavice.
  • 8.3.1 Non-heat-treated processed meat — several limitsAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I, Additives. ML = quantum satis; except E 425 ML = 10000 mg/kg; E 620 to E 625, ML = 10000 mg/kg individually or in combination, expressed as glutamic acid; E 626 to E 635, ML = 500 mg/kg individually or in combination, expressed as guanylic acid.
  • 8.3.2 Heat-treated meat productsAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I, Additives. except foie gras, foie gras entier, blocs de foie gras, Libamáj, libamáj egészben, libamáj tömbben.
  • 8.3.3 Casings and coatings and decorations for meat — several limitsAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I, Additives. ML = quantum satis; except E 425 ML = 10000 mg/kg; E 620 to E 625, ML = 10000 mg/kg individually or in combination, expressed as glutamic acid; E 626 to E 635, ML = 500 mg/kg individually or in combination, expressed as guanylic acid.
  • 9.1.2 Unprocessed molluscs and crustaceans — quantum satisAuthorised under E 500, Sodium carbonates. quantum satis. only frozen and deep-frozen cephalopods. Note 95: may not be used in combination with Phosphoric acid — phosphates — di-, tri- and polyphosphates (E 338-452)’.
  • 9.2 Processed fish and fishery products including molluscs and crustaceans — several limitsAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I, Additives. ML = quantum satis; except E 425 ML = 10000 mg/kg; E 620 to E 625, ML = 10000 mg/kg individually or in combination, expressed as glutamic acid; E 626 to E 635, ML = 500 mg/kg individually or in combination, expressed as guanylic acid.
  • 9.3 fish roeAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I, Additives. only processed fish roe.
Regulation (EC) No 1333/2008, Annex IIand 80 further provisionsretrieved 2026-10-18
Great BritainFood Standards Agency / Food Standards ScotlandPermitted, with conditions

77 food categories

highest permitted level 70,000 mg/kg or mg/l

Show every food category
  • 1.3 Unflavoured fermented milk products, heat-treated after fermentation — quantum satisAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I. quantum satis.
  • 1.4 Flavoured fermented milk products including heat-treated products — quantum satisAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I. quantum satis.
  • 1.6.3 Other creams — quantum satisAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I. quantum satis.
  • 1.7.1 Unripened cheese excluding products falling in category 16 — quantum satisAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I. quantum satis. except mozzarella.
  • 1.7.5 Processed cheese — quantum satisAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I. quantum satis.
  • 1.7.6 Cheese products (excluding products falling in category 16) — quantum satisAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I. quantum satis.
  • 1.8 Dairy analogues, including beverage whiteners — quantum satisAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I. quantum satis.
  • 1.9 Edible caseinates — quantum satisAuthorised under E 500, Sodium carbonates. quantum satis.
  • 10.2 Processed eggs and egg products — quantum satisAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I. quantum satis.
  • 11.2 Other sugars and syrups — quantum satisAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I. quantum satis.
  • 11.4.1 Table-top sweeteners in liquid form — quantum satisAuthorised under E 500, Sodium carbonates. quantum satis.
  • 11.4.2 Table-top sweeteners in powder form — quantum satisAuthorised under E 500, Sodium carbonates. quantum satis.
  • 11.4.3 Table-top sweeteners in tablets — quantum satisAuthorised under E 500, Sodium carbonates. quantum satis.
  • 12.1.1 Salt — quantum satisAuthorised under E 500, Sodium carbonates. quantum satis.
  • 12.1.2 Salt substitutes — quantum satisAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I. quantum satis.
  • 12.2.2 Seasonings and condiments — quantum satisAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I. quantum satis.
  • 12.3 Vinegars and diluted acetic acid (diluted with water to 4-30 % by volume) — quantum satisAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I. quantum satis.
  • 12.4 Mustard — quantum satisAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I. quantum satis.
  • 12.5 Soups and broths — quantum satisAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I. quantum satis.
  • 12.6 Sauces — quantum satisAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I. quantum satis.
  • 12.7 Salads and savoury based sandwich spreads — quantum satisAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I. quantum satis.
  • 12.8 Yeast and yeast products — quantum satisAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I. quantum satis.
  • 12.9 Protein products, excluding products covered in category 1.8 — quantum satisAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I. quantum satis.
  • 13.1.3 Processed cereal-based foods and baby foods for infants and young children as defined by Commission Directive 2006/125/EC — quantum satisAuthorised under E 500, Sodium carbonates. quantum satis. only as rising agent.
  • 13.1.4 Other foods for young children — quantum satisAuthorised under E 500, Sodium carbonates. quantum satis.
  • 13.1.5.1 Dietary foods for infants for special medical purposes and special formulae for infants — quantum satisAuthorised under E 500, Sodium carbonates. quantum satis. only as rising agent.
  • 13.2 Dietary foods for special medical purposes defined in Directive 1999/21/EC (excluding products from food category 13.1.5) — quantum satisAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I. quantum satis.
  • 13.3 Dietary foods for weight control diets intended to replace total daily food intake or an individual meal (the whole or part of the total daily diet) — quantum satisAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I. quantum satis.
  • 13.4 Foods suitable for people intolerant to gluten as defined by Commission Regulation (EC) No 41/2009 — quantum satisAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I. quantum satis. including dry pasta.
  • 14.1.2 Fruit juices as defined by Directive 2001/112/EC and vegetable juices — quantum satisAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I. quantum satis. only vegetable juices.
  • 14.1.3 Fruit nectars as defined by Directive 2001/112/EC and vegetable nectars and similar products — quantum satisAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I. quantum satis. only vegetable nectars, E 420, E421, E 953, E965, E 966, E 967 and E 968 may not be used.
  • 14.1.4 Flavoured drinks — quantum satisAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I. quantum satis. E 420, E 421, E 953, E 965, E 966 and E 967 may not be used E 968 may not be used except where specifically provided for in this food category.
  • 14.1.5.2 Other — quantum satisAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I. quantum satis. excluding unflavoured leaf tea; including flavoured instant coffee; E 420, E421, E 953, E965, E 966, E 967 and E 968 may not be used in drinks.
  • 14.2.3 Cider and perry — quantum satisAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I. quantum satis. E 420, E421, E 953, E965, E 966, E 967 and E 968 may not be used.
  • 14.2.4 Fruit wine and made wine — quantum satisAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I. quantum satis. E 420, E421, E 953, E965, E 966, E 967 and E 968 may not be used.
  • 14.2.5 Mead — quantum satisAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I. quantum satis. E 420, E421, E 953, E965, E 966, E 967 and E 968 may not be used.
  • 14.2.6 Spirit drinks as defined in Regulation (EC) No 110/2008 — quantum satisAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I. quantum satis. except whisky or whiskey; E 420, E421, E 953, E965, E 966, E 967 and E 968 may not be used except in liqueurs.
  • 14.2.7.1 Aromatised wines — quantum satisAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I. quantum satis. E 420, E421, E 953, E965, E 966, E 967 and E 968 may not be used.
  • 14.2.7.2 Aromatised wine-based drinks — quantum satisAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I. quantum satis. E 420, E421, E 953, E965, E 966, E 967 and E 968 may not be used.
  • 14.2.7.3 Aromatised wine-product cocktails — quantum satisAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I. quantum satis. E 420, E421, E 953, E965, E 966, E 967 and E 968 may not be used.
  • 14.2.8 Other alcoholic drinks including mixtures of alcoholic drinks with non-alcoholic drinks and spirits with less than 15 % of alcohol — quantum satisAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I. quantum satis. E 420, E421, E 953, E965, E 966, E 967 and E 968 may not be used.
  • 15.1 Potato-, cereal-, flour- or starch-based snacks — quantum satisAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I. quantum satis.
  • 15.2 Processed nuts — quantum satisAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I. quantum satis.
  • 16 Desserts excluding products covered in categories 1, 3 and 4 — quantum satisAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I. quantum satis.
  • 17.1 Food supplements supplied in a solid form, excluding food supplements for infants and young children — quantum satisAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I. quantum satis. E 410, E 412, E 415, E 417 and E 425 may not be used to produce dehydrated food supplements intended to rehydrate on ingestion.
  • 17.2 Food supplements supplied in a liquid form, excluding food supplements for infants and young children — quantum satisAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I. quantum satis.
  • 18 Processed foods not covered by categories 1 to 17, excluding foods for infants and young children — quantum satisAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I. quantum satis.
  • 2.2.1 Butter and concentrated butter and butter oil and anhydrous milkfat — quantum satisAuthorised under E 500, Sodium carbonates. quantum satis. only soured cream butter.
  • 2.2.2 Other fat and oil emulsions including spreads as defined by Regulation (EC) No 1234/2007 and liquid emulsions — quantum satisAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I. quantum satis.
  • 2.3 Vegetable oil pan spray — quantum satisAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I. quantum satis.
  • 3 Edible ices — quantum satisAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I. quantum satis.
  • 4.2.1 Dried fruit and vegetables — quantum satisAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I. quantum satis. E 410, E 412, E 415 E 417 may not be used to produce dehydrated foods intended to rehydrate on ingestion.
  • 4.2.2 Fruit and vegetables in vinegar, oil, or brine — quantum satisAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I. quantum satis.
  • 4.2.4.1 Fruit and vegetable preparations excluding compote — quantum satisAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I. quantum satis.
  • 4.2.5.4 Nut butters and nut spreads — quantum satisAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I. quantum satis.
  • 4.2.6 Processed potato products — quantum satisAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I. quantum satis.
  • 5.1 Cocoa and chocolate products as covered by Directive 2000/36/EC — quantum satisAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I. quantum satis. only energy-reduced or with no added sugar.
  • 5.1 Cocoa and chocolate products as covered by Directive 2000/36/EC — 70,000 mg/kg or mg/lAuthorised under E 500-504, Carbonates. ML = 70000. Note (*): E 170, E 500-504, E 524-528 and E 530: 7 % on dry matter, without fat, expressed as potassium carbonates (1): The additives may be added individually or in combination.
  • 5.2 Other confectionery including breath refreshening microsweets — quantum satisAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I. quantum satis. The substances listed under numbers E 400, E 401, E 402, E 403, E 404, E 406, E 407, 407a, E 410, E 412, E 413, E 414, E 415, E 417, E 418, E 425 and E 440 may not be used in jelly mini-cups, defined, for the purpose of this Regulation, as jelly confectionery of a firm consistence, contained in semi rigid mini-cups or mini-capsules, intended to be ingested in a single bite by exerting pressure on the mini-cups or mini-capsule to project the confectionery into the mouth; E 410, E 412, E 415 E 417 may not be used to produce dehydrated foods intended to rehydrate on ingestion. E425 may not be used in jelly confectionery.
  • 5.3 Chewing gum — quantum satisAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I. quantum satis.
  • 5.4 Decorations, coatings and fillings, except fruit based fillings covered by category 4.2.4 — quantum satisAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I. quantum satis.
  • 6.2.2 Starches — quantum satisAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I. quantum satis.
  • 6.3 Breakfast cereals — quantum satisAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I. quantum satis.
  • 6.4.2 Dry pasta — quantum satisAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I. quantum satis. only gluten free and/or pasta intended for hypoproteic diets in accordance with Directive 2009/39/EC.
  • 6.4.4 Potato gnocchi — quantum satisAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I. quantum satis. except fresh refrigerated potato gnocchi.
  • 6.4.5 Fillings of stuffed pasta (ravioli and similar) — quantum satisAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I. quantum satis.
  • 6.5 Noodles — quantum satisAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I. quantum satis.
  • 6.6 Batters — quantum satisAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I. quantum satis.
  • 6.7 Pre-cooked or processed cereals — quantum satisAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I. quantum satis.
  • 7.1 Bread and rolls — quantum satisAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I. quantum satis. except products in 7.1.1 and 7.1.2.
  • 7.2 Fine bakery wares — quantum satisAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I. quantum satis.
  • 8.2 Meat preparations as defined by Regulation (EC) No 853/2004 — quantum satisAuthorised under E 500, Sodium carbonates. quantum satis. only poultry meat preparations, mici, bifteki, soutzoukaki, kebap, seftalia, ćevapčići and pljeskavice.
  • 8.3.1 Non-heat-treated meat products — quantum satisAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I. quantum satis.
  • 8.3.2 Heat-treated meat products — quantum satisAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I. quantum satis. except foie gras, foie gras entier, blocs de foie gras, Libamáj, libamáj egészben, libamáj tömbben.
  • 8.3.3 Casings and coatings and decorations for meat — quantum satisAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I. quantum satis.
  • 9.2 Processed fish and fishery products including mollusks and crustaceans — quantum satisAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I. quantum satis.
  • 9.3 Fish roe — quantum satisAuthorised under E 500, Sodium carbonates. Permitted as a member of Group I. quantum satis. only processed fish roe.
Assimilated Regulation (EC) No 1333/2008, Annex II (as at 28 June 2024)and 76 further provisionsretrieved 2026-10-18
JapanConsumer Affairs AgencyNo listing matchedThis site imports only Japan’s list of designated additives (Appended Table 1 to the Regulations for Enforcement of the Food Sanitation Act), matched by English name. Existing additives, natural flavouring agents and ordinary foods used as additives are permitted outside that list and are not imported, so an empty row does not show that Japan does not permit the substance.Related listings with permitted uses here: Sodium bicarbonate (E500), Sodium carbonate (E500). This site cannot tell whether those listings cover this exact form.
South KoreaMinistry of Food and Drug SafetyPermitted, with conditions
Designated food additive: Standards and Specifications for Food Additives, Part III, 1. …

Designated food additive: Standards and Specifications for Food Additives, Part III, 1. 일반식품첨가물 (general food additives), 세스퀴탄산나트륨 (“Sodium Sesquicarbonate”, the English the Code prints beside it). Main use (주용도) of 세스퀴탄산나트륨: 산도조절제, 팽창제. Standard for use (사용기준) of 세스퀴탄산나트륨: (1) [to be used under the general standard for use in II. 2. 1), the minimum amount that achieves the technical effect, with no limit set for this additive in particular] “II. 2. 1)의 규정에 따라 사용하여야 한다.” The Korean is the standard as published. There is no official English translation of the current Code (the English version on MFDS’s website is the 2020 edition and has no legal effect); the English in square brackets is this site’s description of what each sentence does, not a translation of the foods or the levels. Compositional specifications (Part IV) are not imported, nor are the general standards in Part II, which apply to every additive.

Standards and Specifications for Food Additives (식품첨가물의 기준 및 규격), MFDS Notification, Part III (Standards for use, by item)retrieved 2026-10-18
United StatesFood and Drug AdministrationPermitted21 CFR 184.1792retrieved 2026-10-17
Codex AlimentariusCodex Alimentarius Commission / JECFAPermitted, with conditions

6 food categories

no numerical limit (good manufacturing practice)

Show every food category and its notes
  • 01.2.1.2 Fermented milks (plain), heat-treated after fermentation — GMP
    • Note 630 For use in products conforming to the Standard for Fermented Milks (CXS 243-2003) only, as an acidity regulator in flavoured fermented milks and flavoured drinks based on fermented milks that are not heat treated after fermentation, and in plain and flavoured milks and drinks based on fermented milks that are heat treated after fermentation.
  • 01.4.1 Pasteurized cream (plain) — GMP
    • Note 12 Except for use in products conforming to the Standard for Cream and Prepared Creams (CXS 288-1976) as an acidity regulator.
  • 01.4.2 Sterilized and UHT creams, whipping and whipped creams, and reduced fat creams (plain) — GMP
  • 01.8.2 Dried whey and whey products, excluding whey cheeses — GMP
    • Note XS331 Excluding products conforming to the Standard for Dairy Permeate Powders (CXS 331-2017).
  • 09.2.2 Frozen battered fish, fish fillets and fish products, including molluscs, crustaceans, and echinoderms — GMP
    • Note 41 For use in breading or batter coatings only.
  • 12.2.1 Herbs and spices — GMP
    • Note 534 For herbs use is limited to herbs that have been ground or processed into powder only, as an anticaking agent.
    • Note XS326 Excluding products conforming to the Standard for Black, White and Green Peppers (CODEX STAN 326-2017).
    • Note XS351 Excluding products conforming to the Standard for Dried Floral Parts - Saffron (CXS 351-2022).
CXS 192-1995 Table Three, INS 500(iii)and 6 further provisionsretrieved 2026-09-07

How much is permitted

A listing usually limits the quantity as well as the food. Only one of the forms that takes is a figure: quantum satis and good manufacturing practice permit the amount the technological effect requires and no more, which is a limit rather than the absence of one. Figures below are the range across every food category this page is listed in, and categories differ between regulators — see how much is permitted.

European Union70,000 mg/kg1 numeric limit, 46 several limits, 12 quantum satis, 22 no quantity stated
Great Britain70,000 mg/kg1 numeric limit, 76 quantum satis
South Korea—1 no quantity stated
United States—1 no quantity stated
Codex Alimentarius—7 GMP

What it is made from

Mined as the mineral trona, or crystallised from sodium carbonate and bicarbonate together.

  • Vegan
  • Vegetarian

Compare other additives on the dietary indexes.

CAS registry number
533-96-0
InChIKey
WCTAGTRAWPDFQO-UHFFFAOYSA-K
PubChem
CID 10791

The two specifications, compared

The European Union sets identity and purity by regulation; JECFA publishes its own through FAO, advisory until a country adopts it. Both documents are below in full. These are the parameters each puts a number on.

ParameterEuropean UnionJECFA
Assaystated in prosestated in prose
Leadno more than 2 mg/kgno more than 2 mg/kg
Arsenicno more than 3 mg/kg—
Mercuryno more than 1 mg/kg—

The two documents state the same figures for every parameter compared here.

How the EU defines it

The legal specification an additive must meet to be sold as this E number in the EU — what it is, how it may be made, and the purity it must reach. From Commission Regulation (EU) No 231/2012.

E 500(iii) Sodium sesquicarbonate

Assay, identification and purity criteria

Description and assay

Einecs
208-580-9
Chemical name
Sodium monohydrogen dicarbonate
Chemical formula
Na₂CO₃ · NaHCO₃ · 2H₂O
Molecular weight
226,03
Assay
Content between 35,0 % and 38,6 % of NaHCO₃ and between 46,4 % and 50,0 % of Na₂CO₃
Description
White flakes, crystals or crystalline powder

Identification

Test for sodium
Passes test
Test for carbonate
Passes test
Solubility
Freely soluble in water

Purity criteria

Sodium chloride
Not more than 0,5 %
Iron
Not more than 20 mg/kg
Arsenic
Not more than 3 mg/kg
Lead
Not more than 2 mg/kg
Mercury
Not more than 1 mg/kg

Commission Regulation (EU) No 231/2012, Annex, E 500(iii)

How JECFA defines it

The international specification for identity and purity, prepared by the Joint FAO/WHO Expert Committee on Food Additives and published by FAO. It is a different document from any above, written by a different body and revised on its own cycle; it is advisory, and a country adopts it or does not.

INS 500(iii) Sodium Sesquicarbonate

Synonyms: Sodium monohydrogendicarbonate; INS No. 500(iii)

Assay, identification and purity criteria

Description and assay

Specification history
Prepared at the 28th JECFA (1981), published in FNP 31/2 (1984) and in FNP 52 (1992). Metals and arsenic specifications revised at the 59th JECFA (2002). An ADI 'not specified' was established at the 25th JECFA (1981)
Chemical names
Sodium sesquicarbonate, sodium salt of carbonic acid
C.A.S. number
533-96-0
Chemical formula
C 2 HNa 3 O 6 · 2H 2 O Na 2 CO 3 -NaHCO 3 · 2H 2 O
Formula weight
Na 2 CO 3 -NaHCO 3 · 2H 2 O: 226.03 Na 2 CO 3 : 105.99 NaHCO 3 : 84.00
Assay
Between 35.0 and 38.6% of NaHCO 3 Between 46.4 and 50.0% of Na 2 CO 3
DESCRIPTION
White flakes, crystals or crystalline powder
FUNCTIONAL USES
Alkali, buffering agent
METHOD OF ASSAY
NaHCO 3 : Weigh accurately about 8.5 g of the sample in a 250-ml flask, and dissolve it in 50 ml of carbon dioxide-free water. Titrate with 1 N sodium hydroxide until a drop of the solution, when added to a drop of a 1-in-10 solution of silver nitrate TS on a spot plate, produces a dark brown colour. Each ml of 1 N sodium hydroxide is equivalent to 84.01 mg of NaHCO 3 . Na 2 CO 3 : Weigh accurately about 4.2 g of the sample in a 250 ml flask, and dissolve it by adding 100 ml of water. Add 3 drops of methyl orange TS and titrate with 1 N sulfuric acid, stirring vigorously near the end point to expel carbon dioxide. Each ml of 1 N sulfuric acid is equivalent to 30.99 mg of Na 2 O. Calculate the percent of sodium carbonate in the sample by the formula where % NaHCO3 is the percent of sodium bicarbonate determined in the Assay for sodium bicarbonate; 0.3689 is a factor converting NaHCO3 to Na2O and 1.7099 is a factor converting Na2O to Na2CO3.

Identification

Solubility (Vol. 4)
Freely soluble in water
Test for sodium (Vol. 4)
Passes test
Test for carbonate (Vol. 4)
Passes test

Purity criteria

Water
Between 13.8 and 16.7% Calculate the percent of water by subtracting from 100 the sum of the percents of sodium bicarbonate, sodium carbonate, and sodium chloride found in the sample.
Sodium chloride
Not more than 0.5% See description under TESTS
Iron (Vol. 4)
Not more than 20 mg/kg See description under TESTS
Lead (Vol. 4)
Not more than 2 mg/kg Determine using an atomic absorption technique appropriate to the specified level. The selection of sample size and method of sample preparation may be based on the principles of the method described in Volume 4, “Instrumental Methods.”
Test: Sodium chloride
Dissolve about 10 g of the sample, accurately weighed, in 50 ml of water in a 250-ml beaker, add sufficient nitric acid to make the solution slightly acid, then add 1 ml of ferric ammonium sulfate TS, and 1.0 ml of 0.05 N ammonium thiocyanate, and titrate with 0.05 N silver nitrate, stirring constantly, until the red colour is completely discharged. Finally, back titrate with 0.05 N ammonium thiocyanate, until a faint reddish colour is obtained. Subtract the total volume of 0.05 N ammonium thiocyanate added from the volume of 0.05 N silver nitrate required. Each ml of 0.05 N silver nitrate is equivalent to 2.922 mg of NaCl. Calculate the percent of sodium chloride in the sample taken.
Test: Iron
Dissolve 500 mg of the sample in 10 ml of dilute hydrochloric acid TS, and dilute to 50 ml with water. Add about 40 mg of ammonium persulfate crystals and 10 ml of ammonium persulfate crystals and 10 ml of ammonium thiocyanate TS. Any red or pink colour does not exceed that produced by 1.0 ml of Iron Standard Solution (10 μg Fe) in an equal volume of solution containing 2 ml of hydrochloric acid TS and the quantities of ammonium persulfate and ammonium thiocyanate TS used in the test.

FAO JECFA Monograph 1 (2006)

Every name it appears under

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

E number

  • E500

INS number

  • 500(iii)

CAS registry number

  • 533-96-0
  • 72227-05-5

As it appears in regulation

  • Sodium carbonates
  • Sodium sesquicarbonate

Other names

  • Carbicarb
  • Carbonic acid, disodium salt, mixt. with monosodium salt
  • Carbonic acid, sodium salt (2:3)
  • CARBONIC ACID, SODIUM SALT, HYDRATE (2:3:2)
  • E-500(III)
  • HSDB 769
  • INS NO.500(III)
  • INS-500(III)
  • Magadi soda
  • Na2CO3 NaHCO3
  • NaHCO3 Na2CO3
  • SESQUI TM
  • Snowfine
  • Snowflake crystals
  • sodium bicarbonate sodium carbonate
  • Sodium carbonate (3:2)
  • Sodium carbonate hydrogen carbonate (3/1/1)
  • sodium carbonate sodium bicarbonate
  • Sodium carbonate sodium hydrogen carbonate
  • sodium hydrogen carbonate sodium carbonate
  • SODIUM MONOHYDROGENDICARBONATE
  • SODIUM SESQUICARBONATE
  • SODIUM-SALT OF CARBONIC ACID
  • SOLVAY T 200
  • SOLVAY T-200
  • Trisodium hydrogendicarbonate
  • trisodium;hydrogen carbonate;carbonate
  • tron a
  • Trona
  • Urao

Hazard reference values

Values set by assessing bodies. A body that has not set a value is not listed here.
TypeValuePopulationAssessed byOpinion
ADInot specified—JECFA1981

Evidence and how bodies read it

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

Common questions

Assembled from what is above, in the words the questions are usually asked in. Each answer is the same statement the relevant section makes, with the same citations behind it.

What is INS 500(iii)?
INS 500(iii) is Sodium sesquicarbonate. Sodium sesquicarbonate is an alkali used to adjust acidity, midway in strength between bicarbonate of soda and washing soda.
What is Sodium sesquicarbonate used for in food?
It is listed as an acidity regulator — the role Codex and the US assign it. This page shows every function each regulator records, with the citation for each.
Where is Sodium sesquicarbonate permitted?
Of the seven regulators this site reads, the EU, Great Britain, South Korea, the US and the Codex standard permit it. Each permission is for named foods at named levels, not a blanket one; the table on this page gives them with citations.
Is Sodium sesquicarbonate vegan?
Yes. Sodium sesquicarbonate is not derived from animals, and is suitable for vegetarians. This page says what it is made from and how.

Sources for this page

  • eu retrieved 2026-10-18
  • gb retrieved 2026-10-18
  • kr retrieved 2026-10-18
  • ecfr retrieved 2026-10-17
  • gsfa retrieved 2026-09-07
  • euspecs retrieved 2026-10-18
  • jecfaspecs retrieved 2026-09-23

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

Machine-readable: a JSON record of this additive is given on request —how to ask for access.

Follow changes to Sodium sesquicarbonate:Atom feed — regulatory events, and any change the weekly refresh detects in its provisions.