HPLC Determination of 2 Edulcorators and 7 Preservatives in Soybean Products

HPLC was applied to the determination of 2 edulcorators (i.e., acesulfame-K and saccharin sodium) and 7 preservatives (i.e., benzoic acid, sorbic acid, dehydroacetic acid, methylparaben, ethylparaben, propyl p-hydroxybenzoate, butyl p-hydroxybenzoate) in soybean products. The pretreatment methods of the different kinds of samples were described in detail. The C18 column (4.6 mm×250 mm, 5 μm) was used as stationary phase, and a mixture of 0.02 mol·L-1 ammonium acetate solution and methanol in different ratios was used as mobile phase for gradient elution with DAD detector at the wavelength of 236 nm in the determination. Linear relationships between values of peak area and mass concentration of 9 additives were kept in the same range of 0.2-50 mg·L-1, with detection limits (3S/N) in the range of 0.02-0.07 mg·L-1. Tests for recovery and precision were made by standard addition method, values of recovery were found in the range of 97.5%-102% and RSD′s (n=10) ranged from 0.76% to 0.99%.