Occurrence of zearalenone in Korean barley and corn foods

The presence of zearalenone (ZEN) in Korean foods such as barley, barley-based foods, corn, corn-based foods, fruits and vegetables was investigated by direct competitive enzyme-linked immunosorbent assay (dcELISA) and the liquid chromatography (LC) method. A total of 164 samples was collected from Seoul, Korea, in 1998 and 1999 including 30 barley, 32 barley-based foods, 18 corn, 47 corn-based foods, 19 dried red pepper, nine dried jujube, and nine dried persimmon. Average recoveries of ZEN from barley and corn by dcELISA were 138 and 145%, and by LC were 91 and 83% respectively at spiking levels of 5-500 ng g^-1. The detection limit for ZEN was 3 ng g^-1 by dcELISA and 4 ng g^-1 by LC. From 164 samples analysed, ZEN was found by dcELISA in 35 samples (21%) with a mean level of 30 ng g^-1. Barley-based foods had the highest incidence of ZEN (38%) followed by barley (33%), corn-based foods (26%) and corn (22%). No ZEN was detected in any red pepper, jujube or persimmon samples. A high degree of correlation (r²=0.86) was observed between the 35 positive samples detected by dcELISA and 31 samples by LC.