The Dumas method in analytical chemistry is a method for the quantitative determination of nitrogen in chemical substances based on a method first described by Jean-Baptiste Dumas in 1826. An automated instrumental technique has been developed which is capable of rapidly measuring the crude protein concentration of food samples and is now alternative to the Kjeldahl method as the standard method of analysis for protein content for food and animal feeds.
The method consists of combusting a sample of known mass in a high temperature (about 900°C) chamber in the presence of oxygen. This leads to the release of carbon dioxide, water and nitrogen. The gases are then passed over special columns (such as potassium hydroxide aqueous solution) that absorb the carbon dioxide and water.
A column containing a thermal conductivity detector at the end is then used to separate the nitrogen from any residual carbon dioxide and water and the remaining nitrogen content is measured. The measured signal from the thermal conductivity detector for the unknown sample can then be converted into a nitrogen content.
DUMATHERM® technology has established itself as a key component of food and animal feed laboratories. The sturdy, powerful DUMATHERM® system provides valid reference results cleanly, quickly and steadily. Moreover, it can do so in almost any location with the appropriate gas infrastructure.
It is easy to operate, with the DUMATHERM® Manager software providing clear and reliable guidance through the program. Status windows keep you on top of the process at all times. All analytical and device data is saved, forming documentation that enables you to trace at any time all combustion processes that have been carried out. This way, DUMATHERM® efficiently supports quality assurance in an accredited laboratory and takes care of compiling the majority of documentation for you. It also includes different user levels and password protection.