Comparing E172I - Black iron oxide vs E172III - Yellow iron oxide
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Found in 4 products
Found in 2 products
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Search volume over time
Interest over time for 2 keywords in U.S. during the last 10 years.
Interest over time for 2 keywords in U.S. during the last 10 years.
Popular questions
What is black iron oxide used for?
It’s a food colorant (E172) that provides black or gray tones, mainly used in surface decorations and coatings like confectionery, icings, and cheese rinds; it’s also common in capsules and tablets.
How to make black iron oxide?
Food‑grade black iron oxide is made industrially by controlled oxidation/precipitation of iron salts to form magnetite (Fe3O4), then washing, calcining, and milling to strict purity specs—not something to safely or legally produce at home.
Is black iron oxide safe?
Yes—when used within permitted limits it’s considered safe by regulators (e.g., EU E172), is poorly absorbed, and has tight impurity limits; note that allowed uses vary by country.
What is black iron oxide powder?
A fine, insoluble magnetite (Fe3O4) pigment that meets E172 food‑grade specifications and is used to color foods black; it does not meaningfully add dietary iron.
What is iron oxide black?
It’s another name for black iron oxide (magnetite, Fe3O4), the black variant of the E172 iron oxides used as a food color.
What is iron oxide yellow?
Yellow iron oxide (E172III) is a yellow inorganic pigment made of hydrated iron oxide (mainly goethite, FeO(OH)), used as a colorant in foods, pharmaceuticals, and cosmetics; it is insoluble and stable to heat and light.
How to lighten yellow iron oxide?
Lighten it by reducing its dosage or blending with permitted white/neutral colorants or a light-colored base (e.g., calcium carbonate/E170 where allowed); it cannot be chemically bleached without altering the pigment.
How to make yellow iron oxide?
It is produced industrially by oxidizing and precipitating iron salts under controlled pH and temperature to form goethite (FeO(OH)), then washing, filtering, and milling; food‑grade material must meet strict purity limits (e.g., heavy metals).
How to make yellow iron oxide pigment?
Manufacturers form goethite by controlled precipitation/oxidation (e.g., from ferrous sulfate solutions), then age, wash, and mill to the desired shade; heating (calcination) can convert yellow to red hematite, so temperature control is critical.
Iron oxide minerals which might create red or yellow coloration in sandstones?
Red hues are typically from hematite (Fe2O3), while yellow to yellow‑brown tones come from goethite (FeO(OH)) or limonite (hydrated iron oxides); jarosite can also impart yellow coloration in some settings.