Melamine
Definition
1,3,5-triazine-2,4,6-triamine (C3H6N6), a nitrogen-rich compound (66.7% N by mass) used industrially in resins and laminates, illegally added to milk and dairy products to inflate Kjeldahl apparent-protein readings.
- Formula
- C3H6N6
- Nitrogen content
- 66.7% by mass
- Legitimate use
- Resins and laminates
- Illegal use
- Adulterant to inflate apparent milk protein
Common questions
Why does melamine specifically fool the Kjeldahl protein test?+
The Kjeldahl method measures total nitrogen and converts it to a protein estimate using a fixed conversion factor, so any nitrogen-rich compound added to milk, regardless of whether it is actual protein, inflates the calculated protein figure.
How do labs now detect melamine adulteration instead of relying on Kjeldahl alone?+
Labs pair Kjeldahl or Dumas nitrogen testing with a specific method such as LC-MS/MS or ELISA that targets the melamine molecule directly, which distinguishes genuine milk protein nitrogen from nitrogen contributed by an adulterant.
Related terms
- ATR-FTIR
- Attenuated Total Reflectance Fourier-Transform Infrared Spectroscopy: a non-destructive mid-infrared method that analyses a single drop of milk pressed against an ATR crystal....
- Bromocresol Green (BCG) Test
- A colorimetric rapid test for surfactant detergents in milk: BCG at pH 4 partitions into surfactant micelles, shifting from yellow to blue-green...
- Codex Alimentarius
- The FAO/WHO joint food standards programme that sets international reference limits. Its 2012 action levels for melamine (2.5 mg/kg in infant formula,...
- Cryoscopy
- Measurement of milk freezing-point depression (AOAC 961.07). Pure bovine milk freezes at -0.530 to -0.560°C; added water raises (makes less negative) the...
- Diacetyl Monoxime (DAM) Test
- A FSSAI-approved colorimetric rapid test for urea: urea reacts with DAM under acidic conditions to produce a yellow-to-orange chromophore readable at 540...
- FSSAI
- Food Safety and Standards Authority of India, established under the Food Safety and Standards Act 2006 as the central food regulatory body,...
- Kjeldahl Method
- The reference method for protein determination in food: sulphuric acid digestion converts all nitrogen to ammonium sulfate, which is titrated after distillation....
- LC-MS/MS MRM
- Liquid chromatography with triple-quadrupole tandem mass spectrometry operated in multiple reaction monitoring mode. The most sensitive confirmatory method for melamine (primary MRM...
- Melamine-Cyanuric Acid Co-Crystal
- A 1:1 insoluble complex formed when melamine and cyanuric acid co-occur in acidic renal urine. The co-crystal precipitates inside renal tubules, causing...