Accurate determination of ochratoxin A in Korean fermented soybean paste by isotope dilution-liquid chromatography tandem mass spectrometry. (1st January 2016)

• Record Type: Journal Article
• Authors: Ahn, Seonghee; Lee, Suyoung; Lee, Joonhee; Kim, Byungjoo
• Is Part Of: Food chemistry. Volume 190(2016)
• Page Start: 368
• Page End: 373
• Publication Date: 2016-01-01
• Subjects: Ochratoxin A (PubChem CID: 1001246); Ochratoxin A -- Fermented soybean paste -- Isotope dilution mass spectrometry; Food -- Analysis -- Periodicals; Food -- Composition -- Periodicals; 664
• DOI: 10.1016/j.foodchem.2015.05.114
• Languages: English
• ISSNs: 0308-8146

Abstract

Highlights: Development of ID-LC/MS/MS method for the analysis of ochratoxin A in doenjang. Mobile phase pH conditions were optimised. Method was validated with fortified samples. Performance of method (repeatability, reproducibility, uncertainty) was evaluated. Method was applied to various food matrices. Abstract: Ochratoxin A (OTA), a naturally occurring mycotoxin, has been frequently detected in doenjang, a traditional fermented soybean paste, when it is fermented under improper conditions. Reliable screening of OTA in traditional fermented soybean paste (doenjang) is a special food-safety issue in Korea. Our laboratory, the National Metrology Institute of Korea, established an isotope dilution-liquid chromatography tandem mass spectrometry (ID-LC/MS/MS) method as a higher-order reference method to be used for SI-traceable value-assignment of OTA in certified reference materials (CRMs). 13 C20 -OTA was used as an internal standard. Sample preparation conditions and LC/MS measurement parameters were optimised for this purpose. The analytical method was validated by measuring samples fortified with OTA at various levels. Repeatability and reproducibility studies showed that the ID-LC/MS/MS method is reliable and reproducible within 2% relative standard deviation. The analytical method was applied to determine OTA in various commercial doenjang products and home-made doenjang products.