Accuracy
The accuracy of the method was
performed on blank noodle samples spiked
with known quantities of preservatives.
Five known amount of benzoic acid and
sorbic acid were added in blank samples,
mixed and all samples were treated and
analyzed as described above. Three samples
were prepared at each concentration. The
percentage recovery of added preservatives
was calculated by comparing the peak area
of the test samples with that of the standard
solutions. The results obtained from 15
samples are summarized in Table 3. The
mean recoveries ranged from 98.92-102.04%
for benzoic acid and 97.66-102.47% for
sorbic acid excepting at the lowest spiked level
of each compound that was 85.61 and
83.62%, respectively. The RSD value of each
spiked concentration was < 1% and all RSD
values (n=15) were < 8%.Method accuracy was also demonstrated
by plotting the amount of benzoic acid and
sorbic acid found against the amount added.
Method accuracy of benzoic acid (y = 1.026x-
0.615) and sorbic acid (y= 1.032x-0.172)
showed good linearity with r2
0.9990 and
0.9999, respectively. The result is found to be
satisfactory for intended purpose and is
adequate for routine analysis.