What it is
Glycine is the smallest amino acid, and two of them will wrap a ferrous ion into a neutral chelate held by both nitrogen and oxygen donors. That ring structure is what shields the iron. Manufacture reacts a ferrous salt with glycine under controlled pH and temperature in the absence of excess oxygen, after which the product is dried and milled. Specification attention falls on the proportion of iron still in the ferrous state, on free glycine, and on moisture, since all three track how well the chelate has been made and stored.
Formulation considerations
The chelate’s value is in what it stops doing. Free ferrous ions are powerful oxidation catalysts; bound ones are much less so, which is why bisglycinate is the usual choice when iron must sit alongside ascorbic acid, vitamin A or an unsaturated oil in the same premix. It is not inert, though, and co-formulation with those ingredients still needs stability data rather than an assumption. Taste impact in chewables and powders is considerably lower than with sulphate. The powder flows reasonably and compresses well, with no special lubricant demands. Oxidation during wet granulation or in high-moisture gummy bases is the main process risk and is managed with reduced hold times and antioxidant support.
Applications
The ingredient is used in iron tablets and capsules, prenatal and multivitamin formulations, mineral premixes, flour and cereal fortification, beverage sachets, and gummies and chewables. Available in bulk quantities, with pricing on application.
Applications
- Tablets and capsules
- Vitamin and mineral premixes
- Prenatal and multivitamin formulations
- Flour and cereal fortification
- Beverage powders and sachets
- Gummies and chewables
Handling and storage
Store in sealed original packaging below 25°C in a dry, dark store with relative humidity under 55%. Typical shelf life is 24 to 36 months unopened. Ferrous iron oxidises to the ferric state on exposure to moisture and air, which shifts colour toward brown and reduces ferrous assay, so keep liners sealed, weigh promptly and avoid open storage of partial drums.
Common questions
How much elemental iron does iron bisglycinate contain?
Typically 19% to 21% by weight, so roughly 5 g of the chelate supplies about 1 g of elemental iron. Use the lot-specific figure from the Certificate of Analysis when calculating the inclusion rate.
Why choose iron bisglycinate over ferrous sulphate?
In formulation terms the chelate is much less aggressive. It contributes less metallic astringency, causes less colour and flavour drift in fortified foods, and does less oxidative damage to sensitive co-ingredients such as ascorbic acid and vitamin A. Ferrous sulphate is cheaper per unit of iron.
Does iron bisglycinate still discolour a fortified product?
Less than the simple iron salts, but it is not colour-neutral. The light grey powder can shift a white matrix slightly, and oxidation during a wet process will push colour toward brown. Colour should be assessed on the finished product across shelf life.
Is iron bisglycinate compatible with vitamin C in the same premix?
They can be co-formulated and often are, but iron catalyses ascorbic acid oxidation, so stability work is essential. Coating one or both components, controlling premix moisture and using oxygen-barrier packaging are the usual mitigations.