ISO 5544:1978

Caseins — Determination of ” fixed ash ” (Reference method)

Covers caseins obtained by acid precipitation or lactic fermentation, ammonium caseinates, their mxtures with rennet casein and with caseinates, and caseins of unknown type. The principle of determination consists in incinerating a test portion at a temperature of 825 +/- 25 degrees centigrade in the presence of magnesium acetate to bind all phosphorus af organic origin, weighing the residue and subtracting the mass of ash originating from the magnesium acetate.