Inactivation of Enterobacter sakazakii in Infant Milk Formula by Gamma Irradiation: Determination of D₁₀‐Value

Abstract

Enterobacter sakazakii is an emerging foodborne pathogen that has caused several cases of meningitis and necrotizing enterocolitis in infants and has been associated with infant formulas. Five strains of E. sakazakii were inoculated individually into brain heart infusion broth and rehydrated or dehydrated infant milk formula and exposed to ionizing radiation. E. sakazakii strains in brain heart infusion broth and rehydrated infant milk formula (RIMF) were exposed to irradiation dose of up to 1 kGy while strains in dehydrated infant milk formula (DIMF) were exposed to irradiation dose of up to 9 kGy. The D(10)-values were determined by using a linear regression model. Average calculated D(10)-values ranged from 0.21 to 0.29 kGy, 0.24 to 0.37 kGy, and 1.06 to 1.71 kGy in brain heart infusion broth, RIMF, and DIMF, respectively. The results obtained from this study will be useful for powdered infant milk formula industries to reduce the risk associated with E. sakazakii.

Inactivation of Enterobacter sakazakii, Bacillus cereus, and Salmonella typhimurium in powdered weaning food by electron-beam irradiation

“…These results indicate that D 10 -value of the microorganisms depend on sample thickness, initial microbial load, physicochemical properties of the sample, and irradiation and storage conditions (Lee et al, 1998(Lee et al, , 2000. In particular, the D 10 -value for E. sakazakii in our study is higher than those of other studies (Lee et al, 2007;Osaili et al, 2007). Lee et al (2007) have reported that the D 10 -value for E. sakazakii is 0.76 kGy for dehydrated infant formula using gamma irradiation.…”

“…Lee et al (2007) have reported that the D 10 -value for E. sakazakii is 0.76 kGy for dehydrated infant formula using gamma irradiation. Osaili et al (2007) also have reported that the D 10 -value is 1.71 kGy for dehydrated infant milk formula. However, it should be noted that the sample in our study was different, because powdered weaning food made from a particular formula containing rice and rice flour was used as a sample.…”

“…Osaili et al (2007) have reported that E. sakazakii in dehydrated infant formula needs gamma irradiation of 5.13 kGy to obtain 3 log reduction. Sarrias et al (2003) also have reported that B. cereus in raw rice was eliminated by radiation at 7.5 kGy.…”

Effect of electron beam treatments on degradation kinetics of polylactic acid (PLA) plastic waste under backyard composting conditions

“…A D value represents the dose required to cause one log cycle change in a measured parameter. [18][19][20] Here, we used D value to describe the irradiation dose required to change molecular weight by one log cycle and D values were calculated for composted samples after 0, 1, 2 and 6 weeks.…”

Synergistic Bactericidal Effect of Simultaneous Near-Infrared Radiant Heating and UV Radiation against Cronobacter sakazakii in Powdered Infant Formula

“…Recently, some authors have proposed several decontamination methods in an effort to reduce levels of C. sakazakii in powdered infant formula, including gamma radiation (16,17), electron beam irradiation (18), supercritical carbon dioxide and heat treatment (19), and gaseous ozone treatment (20). However, all of these methods have limitations for industrial application because of high capital costs for installation and treatment.…”