TY - JOUR
T1 - Direct application of supercritical carbon dioxide for the reduction of Cronobacter spp. (Enterobacter sakazakii) in end products of dehydrated powdered infant formula
AU - Kim, S. A.
AU - Kim, O. Y.
AU - Rhee, M. S.
N1 - Funding Information:
This work was supported by the Korea Research Foundation Grant funded by the Korea Government (MOEHRD; KRF-2007-311-F00036 ). The authors thank the Korea University Food Safety Center (Seoul, South Korea) for providing the equipment and facilities.
PY - 2010/5
Y1 - 2010/5
N2 - The objective of this study was to develop a viable new method for inactivation of Cronobacter spp. that could be applied directly to dehydrated powdered infant formula (PIF) using supercritical carbon dioxide (SC-CO2). Samples inoculated with Cronobacter spp. were subjected to SC-CO2 treatment under various conditions (temperature: 63, 68, and 73°C; pressure: 15, 20, and 25MPa; time: 10, 20, and 30min). The survival of Cronobacter spp. was assayed, as were any changes in the quality of the treated PIF. Inactivation of Cronobacter spp. by SC-CO2 was enhanced as temperature and pressure conditions increased (>6.32 log10 cfu/g). In a validation assay using low-level inoculation (3.21 log10 cfu/g), treatment at 73°C and 15MPa for 30min, 20MPa for 20 and 30min, or 25MPa for 20 and 30min reduced Cronobacter spp. to undetectable levels, with no recovery of cell viability. There was no significant change in water activity, pH, and color of the treated PIF. Overall, the optimum conditions for elimination of Cronobacter spp. were determined to be 73°C and 20MPa for 20min. These parameters for effective SC-CO2 treatment are feasibly applicable to end product of dehydrated PIF. The results of our study may contribute to the development of an efficient method for improving the microbiological safety of PIF.
AB - The objective of this study was to develop a viable new method for inactivation of Cronobacter spp. that could be applied directly to dehydrated powdered infant formula (PIF) using supercritical carbon dioxide (SC-CO2). Samples inoculated with Cronobacter spp. were subjected to SC-CO2 treatment under various conditions (temperature: 63, 68, and 73°C; pressure: 15, 20, and 25MPa; time: 10, 20, and 30min). The survival of Cronobacter spp. was assayed, as were any changes in the quality of the treated PIF. Inactivation of Cronobacter spp. by SC-CO2 was enhanced as temperature and pressure conditions increased (>6.32 log10 cfu/g). In a validation assay using low-level inoculation (3.21 log10 cfu/g), treatment at 73°C and 15MPa for 30min, 20MPa for 20 and 30min, or 25MPa for 20 and 30min reduced Cronobacter spp. to undetectable levels, with no recovery of cell viability. There was no significant change in water activity, pH, and color of the treated PIF. Overall, the optimum conditions for elimination of Cronobacter spp. were determined to be 73°C and 20MPa for 20min. These parameters for effective SC-CO2 treatment are feasibly applicable to end product of dehydrated PIF. The results of our study may contribute to the development of an efficient method for improving the microbiological safety of PIF.
KW - Cronobacter spp.
KW - Dehydrated powdered infant formula
KW - Inactivation
KW - Supercritical carbon dioxide
UR - http://www.scopus.com/inward/record.url?scp=77952062426&partnerID=8YFLogxK
U2 - 10.3168/jds.2009-2738
DO - 10.3168/jds.2009-2738
M3 - Article
C2 - 20412898
AN - SCOPUS:77952062426
SN - 0022-0302
VL - 93
SP - 1854
EP - 1860
JO - Journal of Dairy Science
JF - Journal of Dairy Science
IS - 5
ER -