This standard replaces the method for determination of zinc in GB/T 5009.14-2003 “Determination for zinc in foods”, 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 9695.20-2008 “Meat and meat products-Method for determination of zinc”, 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”, NY/T 1201-2006 “Determination of copper, iron and zinc in vegetables and derived products”.
Compared with GB/T 5009.14-2003, the major changes of this standard are as follows:
——the name of this standard has been revised to “National food safety standard Determination of zinc in foods”;
——the dry ashing has been remained, the wet digestion, pressure tank digestion and microwave digestion have been added in the pretreatment method;
——the flame atomic absorption spectrophotometry has been remained as Method I, and the dithizone colorimetric method has been remained as Method IV;
——the inductive coupling plasma emission spectrometry has been added as Method II;
——the inductive coupling plasma mass spectrometry has been added as Method III;
——the microwave digestion temperature programming and the instrument conditions for reference of the flame atomic absorption spectrometry have been added as annexes.