Magnesium silicate

E number E553aINS 553(i)CAS 1343-88-0

Listed as an anticaking agent by Canada, Codex and the US.

Listed as anticaking agents (CA, US, Codex) · glazing and surface-finishing agents (CA) · formulation aids (US) · lubricants and release agents (CA)
Chemical structure of Magnesium silicate, from PubChem compound 72941442
Structure from PubChem CID 72941442 (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.

Magnesium silicate is an anticaking agent used in powdered foods, table salt and confectionery.

Where it is and isn’t permitted

Status of Magnesium silicate 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 ZealandPermitted, with conditions

54 food categories

no numerical limit (good manufacturing practice)

Show every food category
  • 0 Preparations of food additives — GMP
  • 1.1.1 Liquid milk (including buttermilk) — GMPOnly UHT goats milk.
  • 1.1.2 Liquid milk products and flavoured liquid milk — GMP
  • 1.2.2 Fermented milk products and rennetted milk products — GMP
  • 1.3 Condensed milk and evaporated milk — GMP
  • 1.4.1 Cream, reduced cream and light cream — GMPOnly UHT creams and creams receiving equivalent or greater heat treatments.
  • 1.4.2 Cream products (flavoured, whipped, thickened, sour cream etc) — GMP
  • 1.5 Dried milk, milk powder, cream powder — GMP
  • 1.6 Cheese and cheese products — GMP
  • 10.2 Liquid egg products — GMP
  • 10.3 Frozen egg products — GMP
  • 10.4 Dried or heat coagulated egg products — GMP
  • 11.1.1 Rainbow sugar — GMP
  • 11.3.1 Dried honey — GMP
  • 11.4 Tabletop sweeteners — GMP
  • 12.1.2 Reduced sodium salt mixture — GMP
  • 12.1.3 Salt substitute — GMP
  • 12.5 Yeast and yeast products — GMP
  • 12.6 Vegetable protein products — GMP
  • 13.3 Formulated meal replacements and formulated supplementary foods — GMP
  • 13.4 Formulated supplementary sports foods — GMP
  • 13.5 Food for special medical purposes — GMP
  • 14.1.1.2 Carbonated, mineralised and soda waters — GMP
  • 14.1.2.1 Fruit and vegetable juices — GMPFor juice separated by other than mechanical means only.
  • 14.1.2.2 Fruit and vegetable juice products — GMP
  • 14.1.3 Water based flavoured drinks — GMP
  • 14.1.4 Formulated Beverages — GMP
  • 14.1.5 Coffee, coffee substitutes, tea, herbal infusions and similar products — GMP
  • 14.2.3 Wine based drinks and reduced alcohol wines — GMP
  • 14.2.4.1 Fruit wine products and vegetable wine products — GMP
  • 14.2.5 Spirits and liqueurs — GMP
  • 14.3 Alcoholic beverages not included in item 14.2 — GMP
  • 2.1 Edible oils essentially free of water — GMP
  • 2.2.1.2 Butter products — GMP
  • 2.2.1.3 Margarine and similar products — GMP
  • 2.2.2 Oil emulsions (<80% oil) — GMP
  • 20 Foods not included in items 0 to 14 — GMP
  • 3 Ice cream and edible ices — GMP
  • 4.1.3 Fruits and vegetables that are peeled, cut, or both peeled and cut — GMP
  • 4.3 Processed fruits and vegetables — GMP
  • 5.1 Chocolate and cocoa products — GMP
  • 5.2 Sugar confectionery — GMP
  • 5.4 Icings and frostings — GMP
  • 6.3 Processed cereal and meal products — GMP
  • 6.4 Flour products (including noodles and pasta) — GMP
  • 7 Breads and bakery products — GMP
  • 8.2 Processed meat, poultry and game products in whole cuts or pieces — GMP
  • 8.3 Processed comminuted meat, poultry and game products, other than products listed in item 8.3.2 — GMP
  • 8.3.2 Sausage and sausage meat containing raw, unprocessed meat — GMP
  • 8.4 Edible casings — GMP
  • 8.5 Animal protein products — GMP
  • 9.2 Processed fish and fish products — GMP
  • 9.3 Semi preserved fish and fish products — GMP
  • 9.4 Fully preserved fish including canned fish products — GMP
Food Standards Code, Schedule 15, S15—5and 53 further provisionsretrieved 2026-10-17
CanadaHealth CanadaPermitted, with conditions

highest permitted level 4,000 mg/kg

8 permitted uses

Show every permitted use
  • In: Garlic salt; Onion salt. Purpose: Anticaking agent. Limit: If used singly, the amount not to exceed 2.0%. If used in any combination with other anticaking agents, the total combined amount not to exceed 2.0%. — Health Canada, List of Permitted Anticaking Agents (List 1), item M.3(a)
  • In: Icing sugar. Purpose: Anticaking agent. Limit: Not to be used with starch in accordance with paragraph 15.1.5(b) of Volume 15 of the Food Compositional Standards Document. If used singly, the amount not to exceed 1.5%. If used in any combination with other anticaking agents, the total combined amount not to exceed 1.5%. — Health Canada, List of Permitted Anticaking Agents (List 1), item M.3(b)
  • In: Salt. Purpose: Anticaking agent. Limit: If used singly, the amount not to exceed 1.0%, or 2.0% in the case of fine grained salt. If used in any combination with other anticaking agents, the total combined amount not to exceed 1.0%, or 2.0% in the case of fine grained salt. This total combined amount does not include any of propylene glycol, potassium ferrocyanide or sodium ferrocyanide that may be added to the food up to their respective maximum levels of use set out in this list. — Health Canada, List of Permitted Anticaking Agents (List 1), item M.3(c)
  • In: Unstandardized dry mixes. Purpose: Anticaking agent. Limit: Good Manufacturing Practice. — Health Canada, List of Permitted Anticaking Agents (List 1), item M.3(d)
  • In: Unstandardized confectionery. Purpose: Glazing agent. Limit: 4,000 ppm. — Health Canada, List of Permitted Glazing Agents (List 7), item M.1
  • In: Chewing gum. Purpose: Dusting agent. Limit: Good Manufacturing Practice. — Health Canada, List of Permitted Food Additives with Other Purposes of Use (List 8), item M.3(a)
  • In: Rice. Purpose: Coating agent. Limit: Good Manufacturing Practice. — Health Canada, List of Permitted Food Additives with Other Purposes of Use (List 8), item M.3(b)
  • In: Unstandardized confectionery. Purpose: Release agent. Limit: Good Manufacturing Practice. — Health Canada, List of Permitted Food Additives with Other Purposes of Use (List 8), item M.3(c)
Health Canadaand 7 further provisionsretrieved 2026-10-17
European UnionEuropean Commission / EFSAPermitted, with conditions

17 food categories

highest permitted level 30,000 mg/kg

Show every food category
  • 1.7.2 ripened cheese — 10,000 mg/kgPermitted as a member of Silicon dioxide - silicates. ML = 10000 mg/kg. only sliced or grated cheese hard and semi-hard cheese. Note 1: The additives may be added individually or in combination.
  • 1.7.5 processed cheese — 10,000 mg/kgPermitted as a member of Silicon dioxide - silicates. ML = 10000 mg/kg. Period of application: from 1 February 2014. Note 1: The additives may be added individually or in combination.
  • 1.7.6 cheese products (excluding products falling in category 16) — 10,000 mg/kgPermitted as a member of Silicon dioxide - silicates. ML = 10000 mg/kg. only sliced or grated hard and semi-hard products Period of application: from 1 February 2014. Note 1: The additives may be added individually or in combination.
  • 1.8 Dairy analogues, including beverage whiteners — 10,000 mg/kgPermitted as a member of Silicon dioxide - silicates. ML = 10000 mg/kg. only sliced or grated cheese analogues and processed cheese analogue; beverage whiteners Period of application: from 1 February 2014.
  • 11.1 Sugars and syrups as defined by directive 2001/111/ec — 10,000 mg/kgPermitted as a member of Silicon dioxide - silicates. ML = 10000 mg/kg. only dried powdered foods Period of application: from 1 February 2014. Note 1: The additives may be added individually or in combination.
  • 11.4.2 table-top sweeteners in powder form — 10,000 mg/kgPermitted as a member of Silicon dioxide - silicates. ML = 10000 mg/kg. Period of application: from 1 February 2014. Note 1: The additives may be added individually or in combination.
  • 11.4.3 table-top sweeteners in tablets — quantum satisPermitted as a member of Silicon dioxide - silicates. quantum satis.
  • 12.1.1 Salt — 10,000 mg/kgPermitted as a member of Silicon dioxide - silicates. ML = 10000 mg/kg. Period of application: from 1 February 2014.
  • 12.1.2 salt substitutes — 20,000 mg/kgPermitted as a member of Silicon dioxide - silicates. ML = 20000 mg/kg. Period of application: from 1 February 2014.
  • 12.2.2 Seasonings and condiments — 30,000 mg/kgPermitted as a member of Silicon dioxide - silicates. ML = 30000 mg/kg. only seasoning Period of application: from 1 February 2014. Note 1: The additives may be added individually or in combination.
  • 17.1 food supplements supplied in a solid form excluding food supplements for infants and young children’, — quantum satisPermitted as a member of Silicon dioxide - silicates. quantum satis. Period of application: from 1 February 2014.
  • 17.2 food supplements supplied in a liquid form excluding food supplements for Infants and young children — quantum satisPermitted as a member of Silicon dioxide - silicates. quantum satis. Period of application: from 1 February 2014.
  • 2.2.2 Other fat and oil emulsions including spreads as defined by Regulation (EC) No 1234/2007 and liquid emulsions — 30,000 mg/kgPermitted as a member of Silicon dioxide - silicates. ML = 30000 mg/kg. only tin greasing products Period of application: from 1 February 2014. Note 1: The additives may be added individually or in combination.
  • 2.3 Vegetable oil pan spray — 30,000 mg/kgPermitted as a member of Silicon dioxide - silicates. ML = 30000 mg/kg. only tin greasing products Period of application: from 1 February 2014. Note 1: The additives may be added individually or in combination.
  • 5.2 Other confectionery including breath freshening micro-sweets — quantum satisPermitted as a member of Silicon dioxide - silicates. quantum satis. surface treatment only Period of application: from 1 February 2014. Note 1: The additives may be added individually or in combination.
  • 5.3 chewing gum — quantum satisquantum satis. surface treatment only.
  • 5.4 Decorations, coatings and fillings, except fruit-based fillings covered by category 4.2.4 — quantum satisPermitted as a member of Silicon dioxide - silicates. quantum satis. surface treatment only Period of application: from 1 February 2014.
Regulation (EC) No 1333/2008, Annex IIand 16 further provisionsretrieved 2026-10-18
Great BritainFood Standards Agency / Food Standards ScotlandPermitted, with conditions

18 food categories

highest permitted level 30,000 mg/kg or mg/l

Show every food category
  • 0 All categories of foods — several limitsPermitted as a member of E 551 – 553: Silicon dioxide – silicates. (1) ML 10000: only foods in dried powdered form (i.e. foods dried during the production process, and mixtures thereof), excluding foods listed in Table 1 of Part A of this Annex; (2) quantum satis: only foods in tablet and coated tablet form, excluding the foods listed in Table 1 of Part A of this Annex. Note (1): The additives may be added individually or in combination. Note (57): The maximum level shall apply unless a different maximum level is specified in points 01 to 18 of this Annex in relation to individual foods or categories of foods.
  • 1.7.2 Ripened cheese — 10,000 mg/kg or mg/lPermitted as a member of E 551 – 553: Silicon dioxide – silicates. ML = 10000. only sliced or grated cheese hard and semi-hard cheese Period of application: from 1 February 2014. Note (1): The additives may be added individually or in combination.
  • 1.7.5 Processed cheese — 10,000 mg/kg or mg/lPermitted as a member of E 551 – 553: Silicon dioxide – silicates. ML = 10000. Period of application: from 1 February 2014. Note (1): The additives may be added individually or in combination.
  • 1.7.6 Cheese products (excluding products falling in category 16) — 10,000 mg/kg or mg/lPermitted as a member of E 551 – 553: Silicon dioxide – silicates. ML = 10000. only sliced or grated hard and semi-hard products Period of application: from 1 February 2014. Note (1): The additives may be added individually or in combination.
  • 1.8 Dairy analogues, including beverage whiteners — 10,000 mg/kg or mg/lPermitted as a member of E 551 – 553: Silicon dioxide – silicates. ML = 10000. only sliced or grated cheese analogues and processed cheese analogue; beverage whiteners Period of application: from 1 February 2014. Note (1): The additives may be added individually or in combination.
  • 11.1 Sugars and syrups as defined by Directive 2001/111/EC — several limitsPermitted as a member of E 551 – 553: Silicon dioxide – silicates. (1) quantum satis: only foods in tablet and coated tablet form Period of application: from 1 February 2014; (2) ML 10000: only dried powdered foods Period of application: from 1 February 2014. Note (1): The additives may be added individually or in combination.
  • 11.4.2 Table-top sweeteners in powder form — 10,000 mg/kg or mg/lPermitted as a member of E 551 – 553: Silicon dioxide – silicates. ML = 10000. Period of application: from 1 February 2014. Note (1): The additives may be added individually or in combination.
  • 11.4.3 Table-top sweeteners in tablets — quantum satisPermitted as a member of E 551 – 553: Silicon dioxide – silicates. quantum satis. Period of application: from 1 February 2014.
  • 12.1.1 Salt — 10,000 mg/kg or mg/lPermitted as a member of E 551 – 553: Silicon dioxide – silicates. ML = 10000. Period of application: from 1 February 2014.
  • 12.1.2 Salt substitutes — 20,000 mg/kg or mg/lPermitted as a member of E 551 – 553: Silicon dioxide – silicates. ML = 20000. Period of application: from 1 February 2014.
  • 12.2.2 Seasonings and condiments — 30,000 mg/kg or mg/lPermitted as a member of E 551 – 553: Silicon dioxide – silicates. ML = 30000. only seasoning Period of application: from 1 February 2014. Note (1): The additives may be added individually or in combination.
  • 17.1 Food supplements supplied in a solid form, excluding food supplements for infants and young children — quantum satisPermitted as a member of E 551 – 553: Silicon dioxide – silicates. quantum satis. Period of application: from 1 February 2014.
  • 17.2 Food supplements supplied in a liquid form, excluding food supplements for infants and young children — quantum satisPermitted as a member of E 551 – 553: Silicon dioxide – silicates. quantum satis. Period of application: from 1 February 2014.
  • 2.2.2 Other fat and oil emulsions including spreads as defined by Regulation (EC) No 1234/2007 and liquid emulsions — 30,000 mg/kg or mg/lPermitted as a member of E 551 – 553: Silicon dioxide – silicates. ML = 30000. only tin greasing products Period of application: from 1 February 2014. Note (1): The additives may be added individually or in combination.
  • 2.3 Vegetable oil pan spray — 30,000 mg/kg or mg/lPermitted as a member of E 551 – 553: Silicon dioxide – silicates. ML = 30000. only tin greasing products Period of application: from 1 February 2014. Note (1): The additives may be added individually or in combination.
  • 5.2 Other confectionery including breath refreshening microsweets — quantum satisPermitted as a member of E 551 – 553: Silicon dioxide – silicates. quantum satis. surface treatment only Period of application: from 1 February 2014. Note (1): The additives may be added individually or in combination.
  • 5.3 Chewing gum — quantum satisquantum satis. surface treatment only.
  • 5.4 Decorations, coatings and fillings, except fruit based fillings covered by category 4.2.4 — quantum satisPermitted as a member of E 551 – 553: Silicon dioxide – silicates. quantum satis. surface treatment only Period of application: from 1 February 2014.
Assimilated Regulation (EC) No 1333/2008and 17 further provisionsretrieved 2026-10-18
JapanConsumer Affairs AgencyPermitted, with conditions
Designated additive: Appended Table 1, item 141, ケイ酸マグネシウム (“Magnesium Silicate” in the unofficial English translation). …

Designated additive: Appended Table 1, item 141, ケイ酸マグネシウム (“Magnesium Silicate” in the unofficial English translation). Standards for use — Specifications and Standards for Foods, Food Additives, etc. (MHW Notification No. 370 of 1959), Part II (Food Additives), F (Standards for use), entry ケイ酸マグネシウム: (1) [may be used only for the uses stated; must be removed or broken down before the food is finished] “ケイ酸マグネシウムは、油脂のろ過助剤以外の用途に使用してはならない。また、使用したケイ酸マグネシウムは、最終食品の完成前に除去しなければならない。” The Japanese is the standard as published. There is no official English translation of the Notification; 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 for this additive, in the same Notification, are not imported and are not shown here; nor are the general rules in F 添加物一般, which apply to every additive.

Regulations for Enforcement of the Food Sanitation Act (MHW Ordinance No. 23 of 1948), Appended Table 1retrieved 2026-10-18
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), 규산마그네슘 (“Magnesium Silicate”, the English the Code prints beside it); the Code marks it as also usable as a processing aid; 2. 가공보조제 (processing aids), 규산마그네슘 (“Magnesium Silicate”, the English the Code prints beside it); the Code marks it as also usable as a general food additive. Main use (주용도) of 규산마그네슘: 고결방지제. Standard for use (사용기준) of 규산마그네슘: (1) [may be used only in the foods listed; sets a limit on the amount used] “규산마그네슘은 아래의 식품에 한하여 사용하여야 한다. 규산마그네슘의 사용량은 1. 가공유크림(자동판매기용 분말 제품에 한함)：1% 이하(이산화규소 또는 규산칼슘과 병용할 때에는 각각의 사용량의 합계가 1% 이하) 2. 분유류(자동판매기용에 한함)：1% 이하(이산화규소 또는 규산칼슘과 병용할 때에는 각각의 사용량의 합계가 1% 이하) 3. 식염：2% 이하(이산화규소 또는 규산칼슘과 병용할 때에는 각각의 사용량의 합계가 2% 이하)” Main use (주용도) of 규산마그네슘: 여과보조제. Standard for use (사용기준) of 규산마그네슘: (1) [must be removed before the final food is complete] “규산마그네슘은 최종식품의 완성 전에 제거하여야 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 182.2437retrieved 2026-10-17
Codex AlimentariusCodex Alimentarius Commission / JECFAPermitted, with conditions

8 food categories

highest permitted level 15,000 mg/kg

Show every food category and its notes
  • 01.5.1 Milk powder and cream powder (plain) — GMP
    • Note 544 Except for use in products conforming to the Standard for Milk Products and Cream Powder (CXS 207-1999): bone phosphate (INS 542), calcium carbonate (INS 170(i)), calcium dihydrogen phosphate (INS 341(i)), calcium hydrogen phosphate (INS 341(ii)), calcium silicate (INS 552), magnesium carbonate (INS 504(i)), magnesium dihydrogen phosphate (INS 343(i)), magnesium hydrogen phosphate (INS 343(ii)), magnesium oxide (INS 530), magnesium silicate, synthetic (INS 553(i)), silicon dioxide, amorphous (INS 551), talc (INS 553(iii)), tricalcium phosphate (INS 341(iii)), and trimagnesium phosphate (INS 343(iii)) as anticaking agents only, singly or in combination at 10,000 mg/kg.
    • Note 549 Except for use in products conforming to the Standard for Edible Casein Products (CXS 290-1995): bone phosphate (INS 542), calcium carbonate (INS 170(i)), calcium silicate (INS 552), hydroxypropyldistarch phosphate (INS 1442), magnesium carbonate (INS 504(i)), magnesium oxide (INS 530), magnesium silicate, synthetic (INS 553(i)), microcrystalline cellulose (cellulose gel) (INS 460(i)), powdered cellulose (INS 460(ii)), silicon dioxide, amorphous (INS 551), talc (INS 553(iii)), calcium dihydrogen phosphate (INS 341(i)), calcium hydrogen phosphate (INS 341(ii)), tricalcium phosphate (INS 341(iii)) magnesium dihydrogen phosphate (INS 343(i)), magnesium hydrogen phosphate (INS 343(ii)) and trimagnesium phosphate (INS 343(iii)), as anticaking agents only, singly or in combination at 4,400 mg/kg, noting the total amount of phosphorus shall not exceed 4,400 mg/kg.
  • 01.6.1 Unripened cheese — GMP
    • Note 488 Except for use in products conforming to the Group Standard for Unripened Cheese including Fresh Cheese (CXS 221-2001): silicon dioxide, amorphous (INS 551), calcium silicate (INS 552), magnesium silicate, synthetic (INS 553(i)) and talc (INS 553(iii)) , singly or in combination, as anticaking agents for the surface treatment of sliced, cut, shredded or grated cheese only, at 10,000 mg/kg as silicon dioxide.
    • Note 563 Except for use in products conforming to the Standard for Mozzarella (CXS 262-2006): calcium silicate (INS 552), magnesium silicate, synthetic (INS 553(i)), silicon dioxide, amorphous (INS 551) and talc (INS 553(iii)) for the surface treatment of sliced, cut, shredded or grated low moisture Mozzarella or for the surface treatment of shredded and/or diced high moisture Mozzarella, as anticaking agents only at 10,000 mg/kg, singly or in combination, as silicon dioxide.
    • Note XS273 Excluding products conforming to the Standard for Cottage Cheese (CXS 273-1968).
    • Note XS275 Excluding products conforming to the Standard for Cream Cheese (CXS 275-1973).
  • 01.6.2.1 Ripened cheese, includes rind — GMP
    • Note 459 Except for use at 10,000 mg/kg, singly or in combination: silicon dioxide, amorphous (INS 551), calcium silicate (INS 552), magnesium silicate, synthetic (INS 553(i)) and talc (INS 553(iii)) in products conforming to the Standards for Cheddar (CXS 263-1966), Danbo (CXS 264-1966) Edam (CXS 265-1966), Gouda (CXS 266-1966), Havarti (CXS 267-1966), Samsø (CXS 268-1966), Emmental (CXS 269-1967), Tilsiter (CXS 270-1968), Saint-Paulin (CXS 271-1968) and Provolone (CXS 272-1968), as anticaking agents only: silicates calculated as silicon dioxide.
    • Note 461 For the surface treatment of sliced, cut, shredded or grated cheese for products conforming to the Standards for Cheddar (CXS 263-1966), Danbo (CXS 264-1966) Edam (CXS 265-1966), Gouda (CXS 266-1966), Havarti (CXS 267-1966), Samsø (CXS 268-1966), Emmental (CXS 269-1967), Tilsiter (CXS 270-1968), Saint-Paulin (CXS 271-1968) and Provolone (CXS 272-1968) only as anticaking agents
    • Note 502 Except for use in surface treatment of sliced, cut, shredded or grated cheese only for products conforming to the General Standard for Cheese (CXS 283-1978): silicon dioxide, amorphous (INS 551), calcium silicate (INS 552), magnesium silicate, synthetic (INS 553(i)) and talc (INS 553(iii)) as anticaking agents at 10,000 mg/kg, as silicon dioxide, singly or in combination.
    • Note XS208 Excluding products conforming to the Standard for Cheese in Brine (CODEX STAN 208-1999).
    • Note XS274 Excluding products conforming to the Standard for Coulommiers (CXS 274-1969).
    • Note XS276 Excluding products conforming to the Standard for Camembert (CXS 276-1973).
    • Note XS277 Excluding products conforming to the Standard for Brie (CXS 277-1973).
    • Note XS278 Excluding products conforming to the Standard for Extra Hard Grating Cheese (CXS 278-1978).
  • 01.8.2 Dried whey and whey products, excluding whey cheeses — 10,000 mg/kg
    • Note XS331 Excluding products conforming to the Standard for Dairy Permeate Powders (CXS 331-2017).
  • 11.1.2 Powdered sugar, powdered dextrose — 15,000 mg/kg
    • Note 56 Excluding products where starch is present.
    • Note 465 For products conforming to the Standard for Sugars (CXS 212-1999) as anticaking agents only: Calcium dihydrogen phosphate (INS 341(i)), calcium hydrogen phosphate (INS 341(ii)), tricalcium phosphate (INS 341(iii)), magnesium dihydrogen phosphate (INS 343(i)), magnesium hydrogen phosphate (INS 343(ii), trimagnesium phosphate (INS 343(iii)), magnesium carbonate (INS 504(i)), bone phosphate (INS 542), silicon dioxide, amorphous (INS 551), calcium silicate (INS 552), and magnesium silicate, synthetic (INS 553(i)) singly or in combination but still within prescribed separate individual maximum levels.
  • 12.1.1 Salt — GMP
  • 12.1.2 Salt substitutes — GMP
  • 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 553(i)and 8 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.

Australia and New Zealand—54 GMP
Canada4,000 mg/kg1 numeric limit, 4 GMP, 3 no quantity stated
European Union10,000 mg/kg – 30,000 mg/kg11 numeric limit, 6 quantum satis
Great Britain10,000 mg/kg – 30,000 mg/kg10 numeric limit, 2 several limits, 6 quantum satis
Japan—1 no quantity stated
South Korea—1 no quantity stated
United States—1 no quantity stated
Codex Alimentarius10,000 mg/kg – 15,000 mg/kg2 numeric limit, 7 GMP

What it is made from

Precipitated by reacting a magnesium salt with sodium silicate.

  • Vegan
  • Vegetarian

Compare other additives on the dietary indexes.

CAS registry number
1343-88-0
InChIKey
ZADYMNAVLSWLEQ-UHFFFAOYSA-N
PubChem
CID 72941442

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
Assayno less than 15 %no less than 15 %
Loss on dryingno more than 15 %no more than 15 %
Leadno more than 5 mg/kgno more than 5 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 553a(i) Magnesium silicate

Magnesium silicate is a synthetic compound of which the molar ratio of magnesium oxide to silicon dioxide is approximately 2:5

Assay, identification and purity criteria

Description and assay

Assay
Content not less than 15 % of MgO and not less than 67 % of SiO₂ on the ignited basis
Description
Very fine, white, odourless powder, free from grittiness

Identification

Test for magnesium
Passes test
Test for silicate
Passes test
pH
Between 7,0 and 10,8 (10 % slurry)

Purity criteria

Loss on drying
Not more than 15 % (105 °C, 2 hours)
Loss on ignition
Not more than 15 % after drying (1 000 °C, 20 min)
Water soluble salts
Not more than 3 %
Free alkali
Not more than 1 % (as NaOH)
Fluoride
Not more than 10 mg/kg
Arsenic
Not more than 3 mg/kg
Lead
Not more than 5 mg/kg
Mercury
Not more than 1 mg/kg

Commission Regulation (EU) No 231/2012, Annex, E 553a(i)

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 553(i) Magnesium Silicate, synthetic

Magnesium silicate (synthetic) is manufactured by the precipitation reaction between sodium silicate and a soluble magnesium salt. The aqueous suspension of the precipitate is filtered and the collected solid washed, dried, classified for particle size and packaged. The finest material is intended for use as an anticaking agent and the coarser particles are for use as a filtering aid. The moisture content of the material meant for use as an anticaking agent is kept to less than 15%. Although magnesium silicate is of variable composition, the molar ratio of MgO to SiO2 is approximately 2:5.

Synonyms: INS No. 553(i)

Assay, identification and purity criteria

Description and assay

Specification history
Prepared at the 74 th JECFA (2011) and published in FAO Monographs 11 (2011) superseding specifications prepared at the 61 st JECFA (2003), published in the Combined Compendium of Food Additive Specifications, FAO JECFA Monographs 1 (2005). An ADI ‘not specified’ was established at the 25 th JECFA (1981).
Chemical name
Magnesium silicate
C.A.S. number
1343-88-0
Assay
Not less than 15% of MgO and not less than 67% of SiO2, calculated on the ignited basis.
DESCRIPTION
Very fine, white, odourless powder, free from grittiness
FUNCTIONAL USES
Anticaking agent, filtering aid
METHOD OF ASSAY
Magnesium oxide and silicon dioxide: Weigh about 0.5 g of the sample to the nearest 0.1 mg, in a platinum or nickel crucible, add 5 g potassium hydroxide and 2 g boric acid, mix and melt completely using a torch burner (alkali fusion) and allow to stand at room temperature. Place the reaction product along with crucible in a 250-ml PTFE beaker, add 150 ml hot deionized water and dissolve residue by agitation. Wash the crucible with hot deionized water and remove it. Add 50 ml hydrochloric acid and transfer the contents into a 250-ml volumetric flask. Wash the beaker three times with hot deionized water, transfer the washings to the volumetric flask and make up to volume (Solution A). Prepare the test solution by diluting Solution A with 2% hydrochloric acid solution. Analyze magnesium and silica in the test solution by ICP-AES technique (Vol. 4). Set instrument parameters as specified by the instrument manufacturer and use the analytical lines for Si (251.611 nm) and Mg (279.553 nm). Read the concentration (as μg/ml) of Mg and Si from respective standard curves. Calculate the magnesium oxide and silicon dioxide content of the sample, on the ignited basis, using the formula: 4.1458 x C x DF %MgO (on the ignited basis) = W x [100 – (%LOD+%LOI)] 5.3504 x C x DF %SiO2 (on the ignited basis) = W x [100 – (%LOD+%LOI)] where C is concentration of Mg or Si in the test solution, μg/ml; DF is dilution factor (dilution of Solution A to get test solution); W is weight of sample, g; %LOD is % loss on drying; and %LOI is % loss on ignition.

Identification

Solubility (Vol. 4)
Insoluble in water
pH (Vol. 4)
7.0-11.0 (1 in 10 slurry)
Magnesium (Vol. 4)
Mix about 0.5 g of the sample with 10 ml of dilute hydrochloric acid TS, filter, and neutralize the filtrate to litmus paper with ammonia TS. The neutralized filtrate gives a positive test for magnesium.
Silicate
Prepare a bead by fusing a few crystals of sodium ammonium phosphate on a platinum loop in the flame of a Bunsen burner. Place the hot, transparent bead in contact with the sample, and again fuse. Silica floats about in the bead, producing, upon cooling, an opaque bead with a web-like structure.

Purity criteria

Loss on drying (Vol. 4)
Not more than 15% (for material used as an anticaking agent (105°, 2 h)) Retain the dried sample for determination of loss on ignition.
Loss on ignition (Vol. 4)
Not more than 15% on the dried basis Weigh to the nearest 0.1 mg, 1 g of the dried sample in a tared platinum crucible provided with a cover. Gradually apply heat to the crucible at first, then strongly ignite at 900/1000° for 20 min. Cool, weigh and calculate as percentage.
Free alkali
Not more than 1% (as NaOH) Add 2 drops of phenolphthalein TS to 20 ml of dilute filtrate prepared in the test for Soluble salts (see below), representing 1 g of the sample. Not more than 2.5 ml of 0.1 N hydrochloric acid should be required to discharge the pink colour produced.
Soluble salts
Not more than 3% Boil 10 g of the sample with 150 ml of water for 15 min. Cool to room temperature, and add water to restore the original volume. Allow the mixture to stand for 15 min, and filter until clear. Retain 20 ml of the filtrate for the test Free alkali. Evaporate 75 ml of the filtrate, representing 5 g of the sample in a tared platinum dish on a steam bath to dryness, and ignite gently to constant weight. Cool, weigh and calculate as percentage (the weight of the residue should not exceed 150 mg).
Fluoride (Vol. 4)
Not more than 10 mg/kg Weigh 2.5 g of the sample to the nearest mg and proceed as directed in the Fluoride Limit Test (Method I or III).
Lead (Vol. 4)
Not more than 5 mg/kg Determine using an AAS/ICP-AES technique appropriate to the specified level. The selection of sample size and method of sample preparation may be based on principles of methods described in Volume 4 (under “General Methods, Metallic Impurities”).

FAO JECFA Monograph 11 (2011)

Authorised in other additives, enzymes, flavourings and nutrients

These authorisations are not for use in food. They let this substance be used inside another additive, a food enzyme, a flavouring or a nutrient preparation — often as a carrier — and it reaches food only as part of that product. Annex III to Regulation (EC) No 1333/2008.

PartMay be used inMaximum levelCitation
Annex III, Part 2: Food additives other than carriers in food additivesDry powdered preparations of polyolsNote (1): Except enzymes authorised as food additives.10 000 mg/kg in the preparationRegulation (EC) No 1333/2008, Annex III, Part 2

Every name it appears under

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

E number

  • E553a

INS number

  • 553(i)

CAS registry number

  • 1343-88-0
  • 14987-04-3

As it appears in regulation

  • Magnesium silicate

Other names

  • Ambosol
  • Avibest
  • Britesorb
  • Britesorb 90
  • Britesorb No. 40
  • Caswell No. 533
  • Celkate T 21
  • Chooz
  • E 553a(i)
  • E 553a(ii)
  • EPA Pesticide Chemical Code 072601
  • Florisil
  • Gastomag
  • Haiburaito 1250
  • Haiburaito 325
  • HS-T (silicate)
  • HSDB 5823
  • INS NO.553(I)
  • INS-553(I)
  • Kyowaad 600S
  • Macrosorb M 15
  • Magmasil
  • Magnesium hydrosilicate
  • Magnesium silicate
  • Magnesium silicate (talc)
  • Magnesium silicate, synthetic
  • Magnesium trisilicate
  • Magnesol
  • Magnesol XL
  • Magsorbent
  • Mizuka Life P 1G
  • Mizupearl M 302
  • Naisuton
  • Nikkagel M
  • Novasorb
  • Salisil
  • Sep-Pak Florisil
  • Shimugon M
  • Silicic acid, magnesium salt
  • Silton SS 1
  • Tri-Sil
  • Trinesium
  • Trisomin

Systematic names

  • dimagnesium tetraoxidosilane
  • Dimagnesium trisilicon octaoxide

The EU re-evaluation programme

Every additive authorised in the EU before 20 January 2009 was put back through EFSA by Commission Regulation (EU) No 257/2010, and this one is named in it. What the Regulation required is below; whether the opinion has since been published is not something this site records.

  • To be evaluated by 31 December 2018. Named in Annex II, Part II, point 4 as “Magnesium silicate and trisilicate”, among the additives given priority within its class.

Hazard reference values

Values set by assessing bodies. A body that has not set a value is not listed here.
TypeValuePopulationAssessed byOpinion
ADInot specified—JECFA1982

Evidence and how bodies read it

What assessing bodies concluded

Each conclusion is paraphrased in the body's own framing, from the published opinion linked beneath it. Where bodies differ, both stand; this site does not adjudicate between them or add a view of its own.

  1. EFSA 2018

    The ANS Panel concluded that the safety of calcium silicate (E 552), magnesium silicate and trisilicate (E 553a) and talc (E 553b) as food additives cannot be assessed, citing accumulation of silicon in rat kidney and liver and a lack of reliable longer-term toxicity data. It considered the SCF's group ADI for silicon dioxide and silicates obsolete and recommended revisions to the specifications.

    Source document

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 E 553a?
E 553a is Magnesium silicate. Magnesium silicate is an anticaking agent used in powdered foods, table salt and confectionery.
What is Magnesium silicate used for in food?
It is listed as an anticaking agent — the role Canada, Codex and the US assign it. This page shows every function each regulator records, with the citation for each.
Where is Magnesium silicate permitted?
Of the seven regulators this site reads, Australia and New Zealand, Canada, the EU, Great Britain, Japan, 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 Magnesium silicate vegan?
Yes. Magnesium silicate is not derived from animals, and is suitable for vegetarians. This page says what it is made from and how.

Sources for this page

  • anz retrieved 2026-10-17
  • ca retrieved 2026-10-17
  • eu retrieved 2026-10-18
  • gb retrieved 2026-10-18
  • jp 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

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