Search results
Results from the WOW.Com Content Network
The Kjeldahl method's universality, precision and reproducibility have made it the internationally recognized method for estimating the protein content in foods and it is the standard method against which all other methods are judged. It is also used to assay soils, waste waters, fertilizers and other materials.
The NSI is the amount of Nitrogen in this filtered solution divided by the nitrogen in the initial sample, as measured by the Kjeldahl method. [ 3 ] The relevance of the NSI is based on the fact that proteins are the major biological source of Nitrogen: for various types of protein, there are empirical formulas which correlate the nitrogen ...
The Dumas method has the advantages of being easy to use and fully automatable. It has been developed into a considerably faster method than the Kjeldahl method, and can take a few minutes per measurement, as compared to the hour or more for Kjeldahl. It also does not make use of toxic chemicals or catalysts.
Protein methods are the techniques used to study proteins. There are experimental methods for studying proteins (e.g., for detecting proteins, for isolating and purifying proteins, and for characterizing the structure and function of proteins, [ 1 ] often requiring that the protein first be purified).
Then, the powdered raw or roasted walnuts are air-dried thoroughly. Both the defatted, powdered raw, and roasted walnuts can be utilized as immunogens. Protein concentrations of the defatted powdered immunogens are set through the Kjeldahl method with 46.4% raw defatted walnut and 34.9% roasted defatted walnut. [37]
Johan Gustav Christoffer Thorsager Kjeldahl (Danish pronunciation: [joˈhæn ˈkʰelˌtɛˀl] 16 August 1849 – 18 July 1900), was a Danish chemist who developed a method for determining the amount of nitrogen in certain organic compounds using a laboratory technique which was named the Kjeldahl method after him.
The total nitrogen content of organic matter is mainly formed by the amino groups in proteins. The Total Kjeldahl Nitrogen is a measure of nitrogen widely used in the analysis of (waste) water, soil, food, feed and organic matter in general. As the name suggests, the Kjeldahl method is applied. More sensitive methods are available.
protein by analysis of total nitrogen, either by Dumas or Kjeldahl methods; total fat, traditionally by a solvent extraction, but often now by secondary methods such as NMR; crude ash (total inorganic matter) by combustion at 550 °C; estimated dietary fibre by various AOAC methods such as 985.29