Development of an immobilization and detection method of Enterobacter sakazakii from powdered infant formula

This study was the first conducted in Brazil to evaluate the presence of Enterobacter sakazakii in milk-based powdered infant formula manufactured for infants 0 to 6 months of age and to examine the conditions of formula preparation and service in three hospitals in São Paulo State, Brazil. Samples of dried and rehydrated infant formula, environments of milk kitchens, water, bottles and nipples, utensils, and hands of personnel were analyzed, and E. sakazakii and Enterobacteriaceae populations were determined. All samples of powdered infant formula purchased at retail contained E. sakazakii at <0.03 most probable number (MPN)/100 g. In hospital samples, E. sakazakii was found in one unopened formula can (0.3 MPN/100 g) and in the residue from one nursing bottle from hospital A. All other cans of formula from the same lot bought at a retail store contained E. sakazakii at <0.03 MPN/100 g. The pathogen also was found in one cleaning sponge from hospital B. Enterobacteriaceae populations ranged from 101 to 105 CFU/g in cleaning aids and <5 CFU/g in all formula types (dry or rehydrated), except for the sample that contained E. sakazakii, which also was contaminated with Enterobacteriaceae at 5 CFU/g. E. sakazakii isolates were not genetically related. In an experiment in which rehydrated formula was used as the growth medium, the temperature was that of the neonatal intensive care unit (25°C), and the incubation time was the average time that formula is left at room temperature while feeding the babies (up to 4 h), a 2-log increase in levels of E. sakazakii was found in the formula. Visual inspection of the facilities revealed that the hygienic conditions in the milk kitchens needed improvement. The length of time that formula is left at room temperature in the different hospitals while the babies in the neonatal intensive care unit are being fed (up to 4 h) may allow for the multiplication of E. sakazakii and thus may lead to an increased health risk for infants.

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Biofilm Formation and Low pH Viability of Cronobacter spp. (Enterobacter sakazakii) Isolated from Powdered Infant Formula and Infant Foods in Korea

Korean Journal for Food Science of Animal Resources ◽

10.5851/kosfa.2009.29.6.702 ◽

2009 ◽

Vol 29 (6) ◽

pp. 702-708 ◽

Cited By ~ 7

Author(s):

Sun-Ae Kim ◽

Yu-Mi Lee ◽

Se-Wook Oh ◽

Hyo-Sun Gwak ◽

In-Gyun Hwang ◽

...

Keyword(s):

Infant Formula ◽

Biofilm Formation ◽

Low Ph ◽

Powdered Infant Formula ◽

Enterobacter Sakazakii ◽

Infant Foods

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Evaluation of a Revised U.S. Food and Drug Administration Method for the Detection and Isolation of Enterobacter sakazakii in Powdered Infant Formula: Precollaborative Study

Journal of AOAC International ◽

10.1093/jaoac/92.3.862 ◽

2009 ◽

Vol 92 (3) ◽

pp. 862-872 ◽

Cited By ~ 15

Author(s):

Yi Chen ◽

Thomas S Hammack ◽

Kwang-Young Song ◽

Keith A Lampel

Keyword(s):

Infant Formula ◽

Drug Administration ◽

Validation Study ◽

Real Time Pcr ◽

Food And Drug Administration ◽

Powdered Infant Formula ◽

Enterobacter Sakazakii ◽

Administration Method ◽

Pcr Technology ◽

Atypical Strains

Abstract A revised U.S. Food and Drug Administration (FDA) method for the detection and isolation of Enterobacter sakazakii in powdered infant formula was developed based on real-time PCR technology complemented by culture isolation on chromogenic agars. A validation study was conducted to compare the revised FDAmethod to the reference FDAmethod. Casein and soy powdered infant formula inoculated with morphologically typical and atypical strains of E. sakazakii were analyzed. Valid results were obtained from 360 test portions and controls and showed that the revised FDAmethod is significantly better (P < 0.05) than the reference FDAmethod for the detection of typical E. sakazakii strains and the two methods are equivalent for the detection of atypical E. sakazakii strains.

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Gamma Radiation Sensitivity of Enterobacter sakazakii in Dehydrated Powdered Infant Formula

Journal of Food Protection ◽

10.4315/0362-028x-69.6.1434 ◽

2006 ◽

Vol 69 (6) ◽

pp. 1434-1437 ◽

Cited By ~ 18

Author(s):

J. W. LEE ◽

S. H. OH ◽

J. H. KIM ◽

H. S. YOOK ◽

M. W. BYUN

Keyword(s):

Radiation Dose ◽

Gamma Radiation ◽

Infant Formula ◽

Marked Effect ◽

Radiation Sensitivity ◽

Sensory Properties ◽

Hot Water ◽

Powdered Infant Formula ◽

Enterobacter Sakazakii ◽

Nutritional Studies

The observed Enterobacter sakazakii D10-values for tryptic soy broth and dehydrated powdered infant formula were 0.27 ± 0.05 and 0.76 ± 0.08 kGy, respectively. A decrease of approximately 3 log in the dehydrated powdered infant formula was obtained by irradiation with 3.0 kGy or rehydration with hot water at 80°C. No recoverable bacteria were found in the powdered infant formula irradiated at 5.0 kGy and stored, either before or after rehydration. A radiation dose of up to 5.0 kGy had no marked effect on the sensory properties of the dehydrated powdered infant formula after rehydration and heating. Gamma radiation could potentially be used to inactivate E. sakazakii in dehydrated powdered infant formula; however, nutritional studies need to be conducted before the use of radiation can be recommended.

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Dry Stress and Survival Time of Enterobacter sakazakii and Other Enterobacteriaceae in Dehydrated Powdered Infant Formula

Journal of Food Protection ◽

10.4315/0362-028x-70.9.2111 ◽

2007 ◽

Vol 70 (9) ◽

pp. 2111-2117 ◽

Cited By ~ 113

Author(s):

JUNCAL CAUBILLA BARRON ◽

STEPHEN J. FORSYTHE

Keyword(s):

Infant Formula ◽

Salmonella Enteritidis ◽

Klebsiella Oxytoca ◽

Powdered Infant Formula ◽

Enterobacter Sakazakii ◽

Opportunistic Pathogens ◽

Term Survival ◽

E Coli ◽

Sterile Product

Powdered infant formula is not a sterile product, and opportunistic pathogens could multiply in the reconstituted product, resulting in neonatal infections. In this study, the generation of sublethally injured Enterobacteriaceae during desiccation and their persistence in dehydrated powdered infant formula was assessed during a 2.5-year period. The study included 27 strains of Enterobacter sakazakii, Enterobacter cloacae, Salmonella Enteritidis, Citrobacter koseri, Citrobacter freundii, Escherichia coli, Escherichia vulneris, Pantoea spp., Klebsiella oxytoca, and Klebsiella pneumoniae. The number of sublethally injured cells generated during desiccation was lower for K. oxytoca, Pantoea spp., Salmonella Enteritidis, and capsulated strains of E. sakazakii than for the other Enterobacteriaceae. The Enterobacteriaceae could be divided into three groups with respect to their long-term survival in the desiccated state. C. freundii, C. koseri, and E. cloacae were no longer recoverable after 6 months, and Salmonella Enteritidis, K. pneumoniae, and E. coli could not be recovered after 15 months. Pantoea spp., K. oxytoca, and E. vulneris persisted over 2 years, and some capsulated strains of E. sakazakii were still recoverable after 2.5 years.

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Cronobacter species (formerly known as Enterobacter sakazakii) in powdered infant formula: a review of our current understanding of the biology of this bacterium

Journal of Applied Microbiology ◽

10.1111/j.1365-2672.2012.05281.x ◽

2012 ◽

Vol 113 (1) ◽

pp. 1-15 ◽

Cited By ~ 82

Author(s):

Q.Q. Yan ◽

O. Condell ◽

K. Power ◽

F. Butler ◽

B.D. Tall ◽

...

Keyword(s):

Infant Formula ◽

Current Understanding ◽

Powdered Infant Formula ◽

Enterobacter Sakazakii ◽

Cronobacter Species

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Evaluation of a New Enrichment Broth for Detection of Cronobacter spp. in Powdered Infant Formula

Journal of Food Protection ◽

10.4315/0362-028x.jfp-10-239 ◽

2011 ◽

Vol 74 (3) ◽

pp. 387-393 ◽

Cited By ~ 9

Author(s):

M. A. AL-HOLY ◽

J.-H. SHIN ◽

T. M. OSAILI ◽

B. A. RASCO

Keyword(s):

Infant Formula ◽

Rapid Detection ◽

Brain Heart Infusion ◽

Sodium Deoxycholate ◽

Powdered Infant Formula ◽

Lauryl Sulfate ◽

Enterobacter Sakazakii ◽

Formula Milk ◽

Enrichment Broth ◽

Infant Formula Milk

The aim of this study was to investigate the potential of using Al-Holy–Rasco (AR) medium, a novel broth for detection and isolation of Cronobacter spp. in infant formula milk (IFM). The new medium's composition is generic brain heart infusion broth with the addition of 1% NaCl, 15% sucrose, and 0.80 g/liter sodium deoxycholate as selective ingredients. AR broth outperformed Enterobacteriaceae enrichment broth (EE), Enterobacter sakazakii enrichment broth (ESE), modified lauryl sulfate broth, and milk as enrichment media to stimulate the growth of a cocktail of 10 strains of Cronobacter. Additionally, AR broth significantly suppressed the growth of competing non-Cronobacter Enterobacteriaceae as compared with EE, ESE, modified lauryl sulfate broth, and milk. The recovery of desiccated Cronobacter (1 to 5,000 CFU/100 g) from powdered IFM in the presence of competing non-Cronobacter Enterobacteriaceae was determined by EE, ESE, and AR broth with 10 and 15% sucrose. AR broth with 15% sucrose outperformed all other examined broths and recovered Cronobacter from all samples tested at all Cronobacter concentrations. AR broth must be validated before it can be used for rapid detection and isolation of Cronobacter from powdered IFM.

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