The Japanese “Second Edition: Analytical Methods for Food Additives in Foods” (Notification Eika No. 15, March 30, 2000 [Revised by Notifications Yakuseishokihatsu No. 0624-1 and Yakuseishokanhatsu No. 0624-1*, June 24, 2021], Ministry of Health, Labour and Welfare (MHLW)) includes a section “Benzoic Acid, Sorbic Acid and Their Salts, and Sodium Dehydroacetate”. In the method, benzoic acid, sodium benzoate, sorbic acid, potassium sorbate, calcium sorbate, and sodium dehydroacetate in foods are extracted and purified by steam distillation, then quantified as benzoic acid, sorbic acid, or dehydroacetic acid using liquid chromatography. An octadecylsilyl silica gel-packed column (ODS column) is specified for use. In this application, Silica C18M 4E, an ODS column, was used to analyze nine types of preservatives in accordance with the Analytical Methods for Food Additives in Foods, and all preservatives were confirmed to be well separated. Two wavelengths: 230 nm and 260 nm were used for the detection.

*The version at the time of the application acquisition.

Sample: 20 µL
5 µg/mL each in CH₃OH/H₂O=60/40

1. 1.Benzoic acid
2. 2.Sorbic acid
3. 3.Dehydroacetic acid
4. 4.Methyl p-hydroxybenzoate
5. 5.Ethyl p-hydroxybenzoate
6. 6.Isopropyl p-hydroxybenzoate
7. 7.Propyl p-hydroxybenzoate
8. 8.Isobutyl p-hydroxybenzoate
9. 9.Butyl p-hydroxybenzoate