Kjeldahl Method
Definition
The reference method for protein determination in food: sulphuric acid digestion converts all nitrogen to ammonium sulfate, which is titrated after distillation. The method measures total nitrogen, not protein specifically, making it susceptible to inflation by any non-protein nitrogen source.
Related terms
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Explained in
- Milk and Dairy Adulteration: Melamine, Urea, Detergent and the 2008 China ScandalThe reference method for protein determination in food: sulphuric acid digestion converts all nitrogen to ammonium sulfate, which is titrated after distillatio...