Determination of Aflatoxins in Red Pepper and Kimchi by Ultra-High-Performance Liquid Chromatography with Fluorescence Detection

The determination of aflatoxins in kimchi is essential as it contains red pepper powder which is susceptible to aflatoxin contamination. This study was designed to determine the concentrations of aflatoxin B-1, aflatoxin B-2, aflatoxin G(1), and aflatoxin G(2) in kimchi and red pepper samples from South Korea. The aflatoxins were isolated from the samples using ultrasonic extraction in 70% methanol and an immunoaffinity column. A method for the quantification of aflatoxins in subject samples was developed and validated using ultra high-performance liquid chromatography with fluorescence detection (u-HPLC-FLD). This method showed good inter-day accuracy (86.7-112.6% recovery) and precision (5.2-11.9% relative standard deviation). The aflatoxins were analyzed in 15 samples (n = 390), with a concentration range from 0.20 to 2.33 mu g/kg. In general, the aflatoxin concentrations in dried red pepper and red pepper powders were very low compared with the Korean Food Code (10 mu g/kg aflatoxin B-1). The analytical method was successfully applied to kimchi products for the determination of aflatoxin levels. From the results, the commercial kimchi products were concluded to be safe for human consumption with respect to aflatoxin concentrations.