Elimination of Phenthoate Residues in the Washing and Cooking of Polished Rice

쌀의 취반 중 Phenthoate 농약 잔류분의 제거

  • Kim, Nam-Hyung (Department of Food and Nutrition, Ewha Woman's University) ;
  • Lee, Mi-Gyung (Department of Food and Nutrition, Ewha Woman's University) ;
  • Lee, Su-Rae (Department of Food and Nutrition, Ewha Woman's University)
  • 김남형 (이화여자대학교 식품영양학과) ;
  • 이미경 (이화여자대학교 식품영양학과) ;
  • 이서래 (이화여자대학교 식품영양학과)
  • Published : 1996.06.30


This study was undertaken in order to elucidate the elimination of phenthoate residues by washing and cooking processes of rice which if the most important food crop in Korea. When contaminated rice was washed with distilled water three times, the removal rate of total phenthoate was 51%. The removal rate in the successive washings was 37.3% (wash filtrate 7.8%, wash sediment 29.5%) in the first, 14.3% (wash filtrate 6.2%, wash sediment 8.1%) in the second and 8.9% (wash filtrate 5.8%, wash sediment 3.1%) in the third washings. More than half of the residue was removed by the first washing and most residues were found in the sediment rather than in the filtrate of the rice washings. The residue rate of phenthoate after cooking by an electric rice cooker was 41%, indicating that the removal rate after cooking was 59%, because phenthoate is thermally stable at the cooking temperature. In conclusion, phenthoate residues contaminated in rice grains are grcatly removed in the washing process and it is desirable to wash the grains before cooking in order to decrease the hazards from pesticide residues such as phenthoate. Reduction factor of phenthoate in rice cooking is proposed to be 0.4.