Industrial chemicals · Taylor, TX
Certificate of Analysis

Sample Certificate of Analysis

Sodium Metabisulfite - Food Grade

Food Grade

Category
Inorganic Salts / Slurries (F)
CAS Number
7681-57-4
Revision
1.1

Sample COA. Contact Alliance Chemical with your lot number to request a lot-specific COA.

2D chemical structure of Sodium Metabisulfite - Food Grade
Structure · PubChem
Last reviewed 2026-07-17 by Andre Taki, DOT Hazmat Specialist.

COA · Answer summary

Sample specification reference for Sodium Metabisulfite - Food Grade. Source-record results are reference values, not measurements for your lot.

Assay specification
Not less than 90.0% and not more than 100.5% of Na2S2O5
Grade
Food Grade

Specifications

ParameterSpecificationSource reference resultTest Method
Assay (Na2S2O5)Not less than 90.0% and not more than 100.5% of Na2S2O595.25 %
Description / AppearanceColorless crystals or a white to yellow, crystalline powderPasses test
Arsenic (As)0.0 – 1.0 ppm0.1 ppm
Heavy metals (as Pb)0.0 – 10.0 ppm0.5 ppm
IdentificationA 1:10 aqueous solution gives positive tests for Sodium and for SulfitePasses test
Insoluble matter< 0.005 wt. %0.001 %
Lead (Pb)Not more than 2 mg/kg0.1 mg/kg
pH4.0-4.84.4
Screen size, through 20 mesh (U.S. Sieve), % by weight99.0 – 100.0 %99.5 %
Selenium< 5.0 ppm0.1 mg/kg
Chloride (Cl)0.0 – 0.02 %0.005 %
Iron (Fe)Not more than 10 mg/kg2 mg/kg
Sodium thiosulfate (Na2S2O3)0.0 – 0.04 %0.005 %
Sodium sulfite (Na2SO3)0.0 – 0.6 %0.15 %
Mercury (Hg)Not more than 1 mg/kg0.01 mg/kgCold vapour AAS (FCC Mercury Limit Test / AOAC 971.21)
Sulfur dioxide (SO2), availableMin. 65.0%66.2%Iodometric titration (FCC assay procedure)
on no. 4010 - 50 %30 %
through no. 1000 - 15 %7.5 %
through no. 2092 - 100 %96 %

Specification limits and source-record results are reproduced from the current product reference used by the TDS. This sample is not an issued certificate and does not identify a tested lot. Contact Alliance Chemical with the product and lot number for lot-specific documentation.