Nitrogen Determination By Kjeldahl - Standard Acid Method Calculator
Posted by Dinesh onThe calculations for % nitrogen or % protein must take into account which type of receiving solution was used and any dilution factors used during the distillation process. In the equations below, “N” represents normality. “ml blank” refers to the millilitres of base needed to back titrate a reagent blank if standard acid is the receiving solution, or refers to millilitres of standard acid needed to titrate a reagent blank if boric acid is the receiving solution.
This calculator calculates the nitrogen percentage (%) using normality, base of standard acid, weight of sample values.
If it is desired to determine % protein instead of % nitrogen, the calculated % N is multiplied by a factor, the magnitude of the factor depending on the sample matrix. Many protein factors have been developed for use with various types of samples.Here you can see the % Nitrogen, the Protein factor and the % Protein for different types of food:
Nitrogen Determination By Kjeldahl - Standard Acid Method
Formula:
% Nitrogen = [((ml standard acid x N of acid) - (ml blank x N of base)) - (ml standard base x N of base) x 1.4007] ÷ WS
Where, N is normality
ml blank is millilitres of base needed to back titrate a reagent blank if standard acid is the receiving solution
SW is weight of sample