Sodium Metabisulfite/Sodium Meta Bisulphite
In the chemical and pharmaceutical industry, sodium metabisulfite
is mainly used as reduction agent. Furthermore, it is ideal for the
bleaching of vegetable fibers and textile, for the production of
solutions, which are used in the developing of photos and films as
well as for the treatment of tanning agents in dyeing of textiles.
ChoiceChem offers different sodium metabisulfite grades, all
meeting highest quality standards.
|DOT Classification:||Not a DOT controlled material|
|Packing Group:||Not applicable.|
Storage & Handing
Precautions for safe handling
Use only in well-ventilated areas. Avoid dust formation.
Protection against fire and explosion:
The substance/product is non-combustible. No special precautions
Conditions for safe storage, including any incompatibilities
Segregate from acids and acid forming substances. Segregate from
Do not store with: Sodium nitrate, sodium nitrite, sodium sulfide
Further information on storage conditions:
Keep container tightly closed and dry; store in a cool
place. Keep container in a well-ventilated place.
Sodium Metabisulfite Food Grade Specifications
|Purity (AS Na2S2O5 )||97.0% Min||97.6%|
|Sulfur Dioxide (SO2)||65.0% Min||65.8%|
|Arsenic (As)||0.0002% Max||0.00005%|
|Heavy Metals (As Pb)||0.0005% Max||0.0003%|
|Selenium (Se)||0.0005% Max||0.00006%|
|Iron (Fe)||0.002% Max||0.001%|
|Water Insoluble||0.02% Max||0.014%|
|5. CAS No||7681-57-4|
|6. HS CODE||28321000|
|7. EINECS No||231-673-0|
► Molecular Formula: Na2S2O5
► CAS No.: 7681-57-4
► Other name: sodium metabisulphite, sodium pyrosulfite
► Physical appearance: white or slightly yellowish crystalline
Sodium Metabisulfite Food Grade
Application of sodium metabisulfite in food industry
Sodium Metabisulfite is widely used in food industry. Besides
bleaching effect, Sodium Metabisulfite also owns the following
1) Sodium Metabisulfite in food has anti-browning effects.
Enzymatic browning often occurs in fruit, potato food. Sodium
Metabisulfite is a kind of reducing agent, has a strong inhibitory
effect on the polyphenol oxidase activity. 0.0001% of sulfur
dioxide can reduce 20% of the enzyme activity, 0.001% of sulfur
dioxide can completely inhibit the enzyme activity and can prevent
enzymatic browning; In addition, can consume oxygen in food
organization and has deoxidation effect. Furthermore, sulfite and
glucose can have addition action, prevent glucose and amino acids
in food ammonia reaction sugar ammonia reaction, so as to own the
function of anti-browning.
2) Sodium Metabisulfite in food has antiseptic effect. Sodium
Metabisulfite can play the role of acidic preservative, the
undissociated sulfurous acid is considered it can inhibit yeasts,
moulds and bacteria. The inhibition of undissociated sulfurous acid
for colon bacillus is 1000 times stronger than Hydrogen sulfite,
100 to 500 times stronger than beer yeast, 100 times stronger than
leaf mold. Sulfur dioxide in the acid has the most powerful anti
3) Sodium Metabisulfite in food has loosen machine effect, Sodium
Metabisulfite can be used as the constituent of loosen machine.
4) Sodium Metabisulfite in food has oxidation resistance effect.
Sodium Metabisulfite has distinctive resistance effect. Sulfurous
acid is strong reducing agent, it can consume the oxygen in
organization of fruits and vegetables, inhibit the activity of
inhibit the activity of oxidizing enzyme, it is effective to
prevent oxidation and breaking of vitamin C in fruits and
The mechanism Sodium Metabisulfite effects: Decolorizers can be
divided into two types by its function: oxidation type bleaching
agent & reducing type bleaching agent. Sodium Metabisulfite
belongs to reducing type bleaching agent.
Sodium Metabisulfite effects decoloring function by pigment
reducing action, so as to achieve the purpose of bleaching. The
colors of most organics are produced by chromophore its molecules
contains. All of chromophore contains unsaturated bood, reduction
bleaching agents release hydrogen atoms, it can make unsaturated
bood in chromophore become single bond, so organics loses color.
The browning of some foods is caused by existing of ferric ion, to
add reduction bleaching agents can make ferric ion become two
valence iron ion, prevent browning of food.
Sodium Metabisulfite effects fading function by addition reaction
of sulfite. So as to achieve the purpose of bleaching. Sodium
Metabisulfite can contact glycosides and carbohydrates to make
addition reaction to bleach and fade. This action is reversible,
sulphurous acid can be removed by heating or acid treatment, to
make anthocyanin regenerate and resume the original red.
Sodium Metabisulfite Products
Sodium Metabisulfite Function
►Nutrient Retention Agent
►Flour dough improver