Potassium alginate

Potassium alginate is the potassium salt of alginic acid (E400), derived from brown seaweed. It functions as a thickener, stabiliser, and gelling agent in a wide range of food products including ice cream, dairy desserts, salad dressings, and restructured food products. Like other alginates, it forms a firm gel in the presence of calcium ions, a property exploited in food manufacturing and molecular gastronomy.

JECFA's ADI is "not specified," evaluated in 1975. Potassium alginate is a largely unabsorbed dietary fibre that passes through the gut with minimal systemic absorption. It provides prebiotic benefits and contributes to total dietary fibre intake. The potassium contribution at food additive concentrations is nutritionally negligible for healthy adults. No adverse effects have been identified at any realistic dietary dose.

Potassium alginate is approved in the EU, US (GRAS), UK, and globally. It is particularly valued as a sodium-free alternative to sodium alginate in reduced-sodium formulations. Individuals with renal disease managing potassium should note its presence, though the amounts from typical food use are small. For the general population it is among the safest food additives available, derived from sustainable seaweed sources.