Page 103 - Analytical method for food addtives

E210–13: Benzoic acid 61

analysis on the filtered extract. A reagent blank should be determined with each
batch of samples. If the blank is 2 mg/kg or more the determination should be
repeated using fresh reagents, otherwise ignore it.

Recovery check
This should be carried out on at least one in every ten samples to be analysed. Using
a standard solution of the five analytes add an appropriate volume (dependent on
sample type) to a further portion of a prepared sample to be analysed, homogenise
and apply the method procedure commencing at ‘Sample Preparation’.

Calculation
Determine the mean value of the two peak areas for each analyte obtained from the
two injections made for each sample extract. Using this mean value obtain from the
calibration graph the concentration of each of the analytes in the extract and hence
calculate the concentration of each analyte in the sample from the formula given
below.
The concentration of each analyte in the sample is given by:

C × 100
Analyte (mg/kg) = ––––––– × f [7.3]
M

where
C = concentration of analyte in extract, mg/L
M = mass of sample, g
f = distribution factor for extract

Expression of results
Report the results as mg/kg.