Rapid detection of melamine in dairy products (kit method)

[Detection principle]

After rapid extraction of the melamine in the sample for about 5 minutes, it reacts with the amine salt precipitation reagent to form a relatively stable suspension.

[Kit configuration]

Test solution A, test solution B, 5mL centrifuge tube, 3mL disposable straw, syringe, closed microporous membrane, turbidity tube, rice-shaped turbidity tablet, 100mg/kg melamine control solution

[Operation method]

(1) Detection of milk and yogurt Take 1mL of 100mg/kg melamine control solution, dilute it to 10mL with milk that does not contain melamine components, take 2.

Use a syringe with a needle to take about 2 mL of the sample supernatant, replace the needle with the closed microporous membrane, and inject it into the turbidity tube.

After 5 minutes, observe from top to bottom and from the side.

(2) Milk powder detection Take 1mL of 100mg/kg melamine control solution, dilute to 10mL with distilled water or purified water, take 0.

Take another 5mL centrifuge tube and add 0.

(3) Feed detection Take 1g of the sample into the turbidimetric tube, add 2mL A test solution, add 2mL purified water, cover and shake vigorously for more than 20 times, and leave it for more than 3 minutes

Use a syringe with a needle to take more than 2 mL of the sample supernatant, replace the needle with the closed microporous membrane, and distribute the liquid evenly into two clean turbidity tubes.

[Precautions]

(1) The purpose of adding "milk or milk powder that is known to be free of melamine components" is to make the matrix of the turbidity liquid the same and to improve the sensitivity of detection

(2) The test should be repeated when a positive result is found, and chromatography should be used for accurate quantification