Comparing E222 - Sodium bisulphite vs E228 - Potassium bisulphite

Synonyms
E222
Sodium bisulphite
Sodium bisulfite
E228
Potassium bisulphite
Potassium bisulfite
Products

Found in 1,804 products

Found in 3 products

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Search volume over time

Interest over time for 3 keywords in U.S. during the last 10 years.

Interest over time for 3 keywords in U.S. during the last 10 years.

Popular questions
  1. Is sodium bisulfite bad for you?

    At approved food-use levels, sodium bisulfite (E222) is considered safe; regulators set a group ADI of 0–0.7 mg/kg body weight expressed as SO2. However, sulfite‑sensitive people—especially some asthmatics—may experience reactions like wheezing, hives, or headaches and should avoid it.

  2. What is sodium bisulfite used for?

    It’s an antioxidant and preservative that prevents browning and oxidation and helps control microbes, commonly used in products like wines, dried fruits, shrimp, and cut potatoes.

  3. What is sodium bisulfite in food?

    It’s a sulfiting agent (E222) that releases sulfur dioxide to protect color and flavor and extend shelf life; it must be declared on labels when present above about 10 ppm (as SO2).

  4. How much sodium bisulfite to neutralize chlorine?

    Approximately 1.5 mg of sodium bisulfite (NaHSO3) is needed per 1 mg of free chlorine (as Cl2) per liter, stoichiometrically. In practice use a slight excess and confirm with a chlorine test; the reaction releases heat and SO2, so handle carefully.

  5. Is sodium bisulfite gluten free?

    Yes—sodium bisulfite is a synthetic mineral salt and contains no gluten; any gluten risk would come from other ingredients, not the additive itself.

  1. How are bisulfite ions generated in the iodine clock reaction potassium iodate and sodium sulfite?

    Bisulfite (HSO3−) comes either directly from dissolving potassium bisulfite (KHSO3 → K+ + HSO3−) or by protonation of sulfite from sodium sulfite in acidic solution (SO3^2− + H+ → HSO3−), which is the pH range used in the iodine clock.

  2. How does sodium bisulfite and potassium iodate react to make iodine reaction with starch?

    In acid, iodate (IO3−) oxidizes bisulfite (HSO3−) to sulfate while being reduced to iodide; once bisulfite is depleted, remaining iodate oxidizes iodide to iodine (I2), which then forms the blue complex with starch.

  3. How does sodium bisulfite and potassium iodate react to make iodine reaction with starch equations?

    Key steps (acidic medium): IO3− + 3 HSO3− → I− + 3 SO4^2− + 3 H+; then IO3− + 5 I− + 6 H+ → 3 I2 + 3 H2O; and while bisulfite remains, it removes iodine: I2 + HSO3− + H2O → 2 I− + HSO4− + 2 H+.

  4. How long is potassium bisulfite good for?

    Stored airtight in a cool, dry place, solid potassium bisulfite is typically usable for about 1–2 years; in solution it loses strength much faster (weeks to a few months) as it oxidizes to sulfate.

  5. How most potassium bisulfite or metab?

    Potassium metabisulfite (E224) is more commonly used because it’s more stable, but both it and potassium bisulfite (E228) release SO2; for dosing, KHSO3 is ~53% SO2 by weight and K2S2O5 is ~58%, so slightly less metabisulfite is needed to achieve the same SO2 level.