Total nitrogen in the samples may be estimated by conventional Micro – Kjeldahl method. Multiply nitrogen contents with suitable factor to calculate crude protein content. Generally, 16% nitrogen is present in proteins. So 100/16 = 6.25 factor may be used to convert nitrogen content to protein. If nitrogen content in protein in a particular crop is more, value of the factor will be low. So, factor for conversion of nitrogen to crude protein varies from crop to crop. Nitrogen present in proteins or other organic compounds reacts with sulphuric acid during digestion and release ammonia, which may be trapped in boric acid or dilute sulphuric acid. Thus nitrogen content may be quantified by titrating it with standard acid or alkali.