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Published on: April 4, 2014
Effect of citrulline, urea, ethanol, and urease on the formation of ethyl carbamate in soybean paste model system
Yong Gun Kim1, Jihye Lyu1, Mina K Kim1
1Department of Food Science and Biotechnology, Dongguk University-Seoul, 30, Pildong-ro 1gil, Jung-gu, Seoul 100-715, Republic of Korea.
Abstract:
The aim of this study was to determine the effect of urease on the formation of ethyl carbamate (EC) in the presence of previously known precursors of EC (citrulline, urea, and ethanol) using a soybean paste model system. The levels of EC were quantitatively determined by gas chromatography-mass spectrometry (GC-MS) every five days for a 30-day period. After 30 days fermentation, the concentration of EC increased significantly by 135.2%, 242.2%, and 3757.1% when the precursors (citrulline, urea and ethanol) were added to the model system, respectively (p<0.05). Urease significantly decreased the level of EC by 38.4%, 18.8%, and 17.3% when citrulline, urea, and ethanol were added to the model system, respectively (p<0.05).
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