Synthetic amorphous silica · E551 / INS 551
Food grade silicon dioxide, also known as amorphous silica (E551 / INS 551), is used as an anticaking agent in suitable powdered foods. Bespring supplies silica for grade-specific evaluation: compare the manufacturing form, food standard, surface area and particle-size method before selecting an anticaking, carrier or beer-processing grade.
Product image · confirm grade and packaging when ordering
*The reference minimum order is 500 kg. Confirm the selected grade, current order terms and required documents in your quotation.
Identity boundaryAmorphous, not crystalline
AnticakingEvaluate flow after storage
Carrier selectionCheck loading and release
Supply reference*10/15 kg bags
A chemical name is not a complete grade
The FAO/WHO JECFA record identifies amorphous silicon dioxide as INS 551, CAS 7631-86-9. Its conventional composition is SiO2. The EFSA 2024 review describes E551 as uncoated, surface-unmodified synthetic amorphous silica (SAS), including fumed and wet-process forms such as precipitated silica, silica gel and hydrous silica.
Crystalline silica, diatomaceous earth, silica fume and surface-modified industrial silica must not be inferred to be this food additive. Request a declaration of manufacturing form, surface treatment and food-grade status for the exact offered grade. A CAS number alone does not demonstrate purity or permission for a particular food.
Start with the required function
Evaluate flow and resistance to caking in the host powder after the expected handling and storage conditions. A fresh-powder flow result alone does not establish shelf-life performance.
Oil absorption indicates loading potential, but release, taste, oxidation and free-flow after loading determine acceptance.
High surface area and pore volume do not alone predict selectivity, filtration pressure or beverage loss. Run process-specific trials.
The two reference grades below are identified by intended use, not by a confirmed manufacturing process. Obtain the current TDS before classifying either as fumed, precipitated or gel silica. For U.S. beer production, 21 CFR 172.480(c) requires removal by filtration before final processing.
Measure the complete powder system
Test flow, caking, adhesion to snacks, dust, color dilution and aroma retention after humidity cycling.
Measure hopper discharge, segregation, dispersibility, sediment, mouthfeel and package stability.
Verify low-dose uniformity, liquid loading, potency recovery, oxidation, compressibility and regulatory scope.
Track flow and clumping under expected humidity, vibration, compression and storage—not only dry-room screening.
Use-level boundary: Codex and national provisions differ by food category and function. In the United States, 21 CFR 172.480(b) allows anticaking use only in foods where the effect has been demonstrated, at no more than reasonably required and no more than 2% by food weight. This is a U.S. legal ceiling, not a recommended formulation dose; beer-stabilizer and specified adsorbent uses have separate conditions. Apply the rule for the actual destination and food.
Commercial reference data
The following commercial reference values describe beer-filtration and dietary-supplement grades. They support grade comparison, not batch acceptance or a claim of compliance with every E551 standard. Agree the identity, limits and test methods in a signed specification, then verify the shipment COA.
Scroll the table horizontally on small screens to compare both grades and the confirmation requirements.
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| Field | Beer filtration grade* | Dietary supplement grade* | Buyer confirmation |
|---|---|---|---|
| SiO2 after ignition | ≥96% | ≥96% | Confirm assay and ignition methods |
| Loss on drying / ignition | ≤7% / ≤8.5% | ≤7% / ≤8.5% | State time, temperature and basis |
| Lead / arsenic | ≤5 / ≤3 mg/kg | ≤5 / ≤3 mg/kg | Compare with current destination and customer limits |
| “Heavy metals as Pb” | ≤30 mg/kg | ≤30 mg/kg | Aggregate test; not the individual lead result or a complete elemental panel |
| Soluble salts | ≤4% | ≤4% | Confirm method and ionic profile if critical |
| Bulk density | <0.3 g/mL | <0.3 g/mL | Clarify loose/tapped and conditioning |
| Surface area | ≥400 m²/g | 190–260 m²/g | BET method and degassing conditions |
| Oil absorption | Not stated | ≥2.0 mL/g | Liquid, endpoint, method and repeatability |
| Average particle size | 8–20 μm | 10–20 μm | Method and distribution missing; average alone is insufficient |
| Pore volume | 0.9–1.6 mL/g | Not stated | Method and pore-size distribution |
| pH | 4.5–9 | 6–8 | Slurry ratio, water and temperature |
| Iron | “25 mg/kg” | Not stated | 25 mg/kg has no acceptance comparator; agree maximum, typical value or range |
The SiO2 assay is reported after ignition, not as elemental silicon or automatically on an as-received basis. Loss on drying and loss on ignition are separate tests; their temperatures, times and sample preparation need to be defined. The iron value “25 mg/kg” has no acceptance symbol. Obtain the approved methods, particle distribution and manufacturing-form declaration before qualification.
The listed lead limit is 5 mg/kg and arsenic limit is 3 mg/kg; these are commercial values, not a statement that every destination standard is met. Compare them using the extraction or digestion method required by your standard. The EFSA 2024 recommendations call for tighter lead, mercury and arsenic limits and an aluminium limit; a scientific recommendation is distinct from an enacted legal specification. Request mercury, aluminium and other customer-required results where applicable.
CAS, INS identity and specification history; the record lists Monograph 20 (2017).
Review the JECFA recordSAS identity, manufacturing forms, particle characterization and impurity recommendations.
Review the EFSA summaryCurrent US anticaking, beer-stabilizer and specified adsorbent conditions.
Review 21 CFR 172.480Formulation validation
Record particle distribution, fat/oil, hygroscopicity, water activity, initial flow and bulk density.
Measure flow function, angle of repose, discharge time and caking force against an untreated control.
Apply humidity cycling, thermal exposure, vibration and compression in the intended packaging.
Confirm appearance, taste, dispersibility, assay recovery, equipment behavior and legal use.
Source-to-line approval
Confirm synthetic amorphous, uncoated/unmodified silica, process form, CAS and E/INS identity.
Align assay, BET, pore volume, oil absorption, particle distribution, density, pH and impurities.
Select anticaking, carrier or beer-processing grade from the actual process requirement.
Compare against a control through realistic humidity, storage, transfer and processing.
Confirm food category, use level, label/processing-aid status and destination documentation.
Approve COA fields, sampling, packaging, shelf life, traceability and change notification. Request current TDS, SDS, representative and batch COA, plus any required certificates for the exact product, manufacturing site and validity period.
Explore the food ingredient application guide or compare food grade tricalcium phosphate and food grade magnesium carbonate for different powder or mineral requirements. These ingredients are not proposed as equal-dose substitutes. See certificate scope guidance when requesting documents.
Packaging and handling photographs
The reference packing is 10 kg and 15 kg kraft paper bags. Unpalletized 20-foot-container reference loads are 5 metric tons for 10 kg bags and 7.5–8.1 metric tons for 15 kg bags. Confirm the selected grade, actual bulk density, pallet plan and shipment loading in the quotation. The packaging images show 25 kg labels; they do not establish 25 kg availability for either listed grade.
Store in a dry, ventilated, uncontaminated room-temperature environment, away from direct sunlight and outdoor exposure, following the current SDS. The reference shelf life is 24 months from production; agree grade-specific storage conditions and shipment dates before ordering.
Buyer questions
Food grade amorphous silicon dioxide is used as an anticaking agent in suitable powdered foods. Selected grades may be evaluated for carrier or specified beer-stabilization uses. The grade, intended function, food category and destination rules determine suitability.
The food-additive identity discussed here is synthetic amorphous silica, not crystalline silica. EFSA describes E551 as uncoated and surface-unmodified. Obtain a grade-specific declaration; an industrial or hydrophobic silica COA does not establish suitability for this food-grade supply.
No. Surface area, pore structure, particle distribution, bulk density and compatibility with the host powder interact. Compare grades using the same methods and assess flow and caking after the intended storage and handling conditions.
No. An average does not describe the full distribution or distinguish primary particles, aggregates and agglomerates. Request the dispersion procedure, instrument and an appropriate distribution such as D10/D50/D90; a micrometre average alone is not a non-nano declaration.
An anticaking grade is evaluated for flow and caking in the host powder. A carrier grade must also satisfy the intended liquid-loading, leakage, release and active-recovery requirements. The two functions do not make grades interchangeable.
No. It is a commercial reference table, not a complete standard comparison or batch COA. Confirm the manufacturing form, assay basis, test methods and all applicable impurity limits against the selected current standard before approval.
The commercial reference lists 10 kg and 15 kg bags, while the packaging images show 25 kg labels. Confirm the actual pack for the quoted grade. The reference minimum order is 500 kg; current order terms and container loading require quotation confirmation.
Request the current signed specification or TDS, SDS and representative COA, followed by the shipment batch COA. Specify any required manufacturing-form, particle-characterization, origin, allergen, food-safety, Halal or Kosher documents; verify availability and product, site and validity scope.
State the food application and destination market, required silica form and food standard, critical purity and physical-property limits, test methods, quantity, packing, destination port, delivery terms and timing. For carrier or beer use, include the relevant loading or process requirements.
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Function-led sourcing
Send your application, required standard and critical parameters so our team can review the grade, documents and commercial requirements.
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An external reference is not a batch certificate or a Bespring product specification.