Process / pipelineAnalytical Chemistry

Kjeldahl Method

The Kjeldahl Method is a classical analytical procedure for determining the total nitrogen content of food products, developed by Johan Kjeldahl in 1883. By measuring total nitrogen and applying a conversion factor specific to the food type, the method indirectly determines crude protein content. Kjeldahl remains the official standard method for protein determination in foods, nutraceuticals, and animal feeds worldwide.

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Sources

  1. Kjeldahl, J. G. C. T. (1883). Neue Methode zur Bestimmung des Stickstoffs in organischen Körpern. Zeitschrift für Analytische Chemie, 22, 366-383. link
  2. AOAC International (2016). Official Methods of Analysis (20th ed.). AOAC International. link

Related methods

ScholarGateKjeldahl Method (Kjeldahl Method). Retrieved 2026-06-04 from https://scholargate.app/en/food-science/kjeldahl-method