TY - JOUR
T1 - Potential use of supercritical carbon dioxide to decontaminate Escherichia coli O157:H7, Listeria monocytogenes, and Salmonella typhimurium in alfalfa sprouted seeds
AU - Jung, W. Y.
AU - Choi, Y. M.
AU - Rhee, M. S.
N1 - Funding Information:
This study was supported by the Miraewon Co. Ltd. The authors thank the Korea University Food Safety Center for allowing the use of their equipments and facilities.
PY - 2009/11/30
Y1 - 2009/11/30
N2 - We sought to develop a method of decontaminating alfalfa sprouts of Escherichia coli O157:H7, Listeria monocytogenes, and Salmonella typhimurium without altering the seed germination capability using supercritical carbon dioxide (SC-CO2). Samples were treated with SC-CO2 at 10, 15, or 20 MPa and temperatures of 35, 40, or 45 °C for 5, 10, or 15 min. The germination percentage was measured after three days of germination. Generally, treating seeds with SC-CO2 at higher pressures, temperatures, or for longer treatment times resulted in greater microbial reductions than treatments at lower pressures, temperatures, or for shorter treatment times. SC-CO2 treatment clearly reduced the microorganism levels in alfalfa seeds; in particular, treatment at 20 MPa and 45 °C for 15 min reduced levels of the three pathogens by > 7.0 log colony forming units (CFU)/g. However, SC-CO2 treatment at a high pressure and high temperature, especially treatment at 20 MPa and 40 or 45 °C, impaired the seed germination capability in some cases. Without impairing the germination capability, the maximum reduction level of E. coli O157:H7 was 3.51 CFU/g with SC-CO2 treatment at 15 MPa and 35 °C for 10 min. Maximum reductions of L. monocytogenes and S. typhimurium were 2.65 and 2.48 log CFU/g, respectively, with treatment at 10 MPa and 45 °C for 5 min. Therefore, our results indicate that SC-CO2 treatment can be used to effectively improve alfalfa seed safety.
AB - We sought to develop a method of decontaminating alfalfa sprouts of Escherichia coli O157:H7, Listeria monocytogenes, and Salmonella typhimurium without altering the seed germination capability using supercritical carbon dioxide (SC-CO2). Samples were treated with SC-CO2 at 10, 15, or 20 MPa and temperatures of 35, 40, or 45 °C for 5, 10, or 15 min. The germination percentage was measured after three days of germination. Generally, treating seeds with SC-CO2 at higher pressures, temperatures, or for longer treatment times resulted in greater microbial reductions than treatments at lower pressures, temperatures, or for shorter treatment times. SC-CO2 treatment clearly reduced the microorganism levels in alfalfa seeds; in particular, treatment at 20 MPa and 45 °C for 15 min reduced levels of the three pathogens by > 7.0 log colony forming units (CFU)/g. However, SC-CO2 treatment at a high pressure and high temperature, especially treatment at 20 MPa and 40 or 45 °C, impaired the seed germination capability in some cases. Without impairing the germination capability, the maximum reduction level of E. coli O157:H7 was 3.51 CFU/g with SC-CO2 treatment at 15 MPa and 35 °C for 10 min. Maximum reductions of L. monocytogenes and S. typhimurium were 2.65 and 2.48 log CFU/g, respectively, with treatment at 10 MPa and 45 °C for 5 min. Therefore, our results indicate that SC-CO2 treatment can be used to effectively improve alfalfa seed safety.
KW - Alfalfa seeds
KW - Foodborne pathogens
KW - Germination rate
KW - Supercritical carbon dioxide
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U2 - 10.1016/j.ijfoodmicro.2009.08.014
DO - 10.1016/j.ijfoodmicro.2009.08.014
M3 - Article
C2 - 19733412
AN - SCOPUS:70350292557
VL - 136
SP - 66
EP - 70
JO - International Journal of Food Microbiology
JF - International Journal of Food Microbiology
SN - 0168-1605
IS - 1
ER -