Foreword

This standard replaces the methods for determination of magnesium specified in GB/T 5009.90-2003 “Determination of iron, magnesium and manganese in foods”, GB/T 9695.21-2008 “Meat and meat products-Method for determination of magnesium content”, GB 5413.21-2010 “National food safety standard-Determination of calcium, iron, zinc, sodium, potassium, magnesium, copper and manganese in foods for infants and young children, milk and milk products”, GB/T 23375-2009 “Determination of copper, iron, zinc, calcium, magnesium and phosphorus content in vegetables and derived products”, GB/T 14609-2008 “Inspection of grain and oils-Determination of copper, iron, manganese, zinc, calcium, magnesium in cereals and derived products by atomic absorption and flame spectrophotometry”, GB/T 18932.12-2002 “Method for the determination of potassium, sodium, calcium, magnesium, zinc, iron, copper, manganese, chromium, lead, cadmium contents in honey-Atomic absorption spectrometry” and NY 82.19-1988 “Method for determination of fruit juice-Determination of calcium and magnesium”.

Compared with GB/T 5009.90-2003, the major changes of this standard are as follows:

——the standard name has been revised to “National food safety standard-Determination of magnesium in foods”;

——the sample pretreatment method has been adjusted to wet digestion, microwave digestion, dry ashing and pressure tank digestion;

——the flame atomic absorption spectrometry has been retained for the sample determination and the titration method has been deleted;

——the inductively coupled plasma emission spectrometry has been added as Method II;

——the inductively coupled plasma mass spectrometry has been added as Method III.