Sodium metabisulfite (Na₂S₂O₅)
Sodium Metabisulfite (Na₂S₂O₅)
High-Purity Antioxidant, Preservative & Reducing Agent for Industrial Applications
Product Identification
Chemical & Physical Information
Product Name: Sodium Metabisulfite
Catalogue Number: ASC-1041
CAS Number: 7681-57-4
Chemical Formula: Na₂S₂O₅
Molecular Weight: 190.11 g/mol
Form: White crystalline powder
Odour: Characteristic sulphur dioxide odour
Product Description
Sodium Metabisulfite (Na₂S₂O₅) is a high-purity inorganic salt widely used as an antioxidant, preservative, disinfectant, and reducing agent across food processing, beverage production, water treatment, mining, textiles, pulp and paper, and photographic industries.
When dissolved in water, sodium metabisulfite releases sulphur dioxide, providing strong antioxidant and antimicrobial activity. Its excellent solubility, fast reaction kinetics, and cost-effectiveness make it a preferred processing aid in applications where oxidation control, microbial inhibition, or chemical reduction is required.
Ausamics Sodium Metabisulfite is supplied as a free-flowing crystalline powder, manufactured under controlled conditions to ensure consistent quality and reliable performance.
Principle of Use
Functional Role
Acts as a reducing agent to prevent oxidative degradation
Inhibits microbial growth through sulphite activity
Neutralises oxidising agents such as chlorine and cyanide
Functions as a bleaching and colour-stabilising agent
Typical Characteristics
Physicochemical Properties
Appearance: White crystalline or powdery solid
Solubility: Highly soluble in water
pH (5 % solution at 20 °C): 4.0 – 5.5
Purity: ≥ 97.0 %
Composition & Specifications
Quality Parameters
Iron (Fe): ≤ 20 ppm
Heavy Metals (as Pb): ≤ 10 ppm
Sulfate Content: ≤ 0.05 %
Typical Applications
Food & Beverage Processing
Wine and beer production as an antioxidant and antimicrobial agent
Preservation of dried fruits and vegetables to prevent enzymatic browning
Juices and beverages to reduce oxidation and extend shelf life
Processing aid in confectionery and baking for colour stabilisation
Water & Wastewater Treatment
Dechlorination of potable and process water
Reduction of residual oxidants prior to environmental discharge
Heavy metal reduction and oxygen scavenging
Mining & Metallurgy
Cyanide detoxification in gold and silver mining
Environmental remediation of process effluents
Textile, Pulp & Paper Industries
Bleaching of wool, cotton, and paper pulp
Improvement of brightness and whiteness
Photography & Technical Use
Component of photographic developers and fixers
General reducing agent in laboratory and industrial workflows
Key Features
Product Advantages
Strong antioxidant and preservative activity
Rapid solubility and fast reaction kinetics
Cost-effective and versatile processing aid
Consistent batch-to-batch quality
Suitable for food, industrial, and technical use where permitted
Safety & Handling
Handling Precautions
Use appropriate personal protective equipment including gloves and eye protection
Avoid inhalation of dust and sulphur dioxide vapours
Ensure adequate ventilation during handling
Refer to the Safety Data Sheet (SDS) for detailed hazard and first-aid information.
Storage & Stability
Storage Conditions
Store in a cool, dry place
Keep container tightly sealed
Protect from moisture and incompatible oxidising substances
Stable under recommended storage conditions
Intended Use
Regulatory Statement
Supplied as an industrial and food-processing raw material.
Intended for manufacturing, processing, laboratory, and industrial applications where permitted.
Not supplied as a finished food product or therapeutic good.
Quality & Supply Assurance
Manufacturing & Documentation
Manufactured under controlled quality systems
Certificate of Analysis (COA) available on request
Safety Data Sheet (SDS) available
Technical support provided by Ausamics Life Science
Customs & Trade Information
Classification
HS / AHECC Code: 2832.10.00
Sodium metabisulfite