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Enterobacter sakazaki may be related to outbreaksof meningitis, septicemia, and necrotizing enterocolitis, mainlyin neonates. To reduce the risk of E. sakazaki in baby fods,E. sakazaki isolates weredetermined at 52, 56, and 60oC in saline solution, rehydratedpowdered infant formula, and dried baby food. In salinesolution, their D-values were 12-16, 3-5, and 0.9-1min foreach temperature. D-values increased to 16-20, 4-5, and2-4 min in rehydrated infant formula and 14-17, 5-6, and2-3 min in dried baby food. The overall calculated z-valuewas 6-8 for saline, 8-10 for powdered infant formula,and 9-1 for dried baby food. Thermal inactivation of E.sakazaki during rehydration of powdered infant formula wasinvestigated by viable counts. Inactivation of cultured E.sakazaki in infant formula milk did not occur for 20 min atroom temperature after rehydration with the water at 50oCand their counts were reduced by about 1-2 log CFU/g at60oC and 4-oC.However, the thermostability of adapted E. sakazakii to thepowdered infant formula increased more than two times.Considering that the levels of E. sakzaki observed inpowdered infant formula have generaly been 1 CFU/100 g ofdry formula or les, contamination with E. sakazakii can bereduced or eliminated by rehydrating water with at least10oC higher temperature than the manufacturer-recomended50oC.