Effect of heat treatment on Cronobacter spp. in reconstituted, dried infant formula: preparation guidelines for manufacturers.
OBJECTIVE
To explore safe guidelines for manufacturers and consumers to prepare, handle and store dry infant formula (DIF) to protect infants against Cronobacter spp.


RESULTS
Selected strains (2.45, FSM 293, ATCC-12868, FSM-271) screened from 68 strains of Cronobacter spp. were used to study growth and survival in commercial DIF. Prototype growth patterns in Enterobacteriaceae enrichment broth (EEB) containing a cocktail comprised of ATCC 12868, ATCC 29004, ATCC 29544 and ATCC 51329 showed a rapid increase in cell count (2.0 log(10) to 6.2 log(10) CFU ml(-1)). Infant formula provided a better protective environment for the cells of Cronobacter strains than did buffered peptone water. Experiments on survival in inoculated (10(4)-10(6) CFU ml(-1)) reconstituted infant formula (RIF), preparation temperature, the effect of preparation volume (one-serving or two-serving) and effect of storage at room temperature for up to 10 h provided information to develop consumer guidelines for DIF preparation and handling.


CONCLUSIONS
Reconstituted DIF in water at >70 degrees C in larger volumes, minimizing storage time before feeding and storing unused reconstituted formulate at <4 degrees C, may reduce the risk of Cronobacter infection in infants.


CONCLUSIONS
Meningitis, necrotizing enterocolitis and bacteremia in premature babies has been linked to contaminated milk powder and DIF; better handling practices may improve the safety of these foods for neonates.
Chen
P-C
PC
Department of Food Science and Human Nutrition, Washington State University, Pullman, 99164-6376, USA.
Zahoor
T
T
Oh
S-W
SW
Kang
D-H
DH
D015169:Colony Count, Microbial; D003257:Consumer Product Safety; D003470:Culture Media; D004755:Enterobacteriaceae / Q000254:growth & development*; D005506:Food Contamination; D005511:Food Handling / Q000592:standards; D005516:Food Microbiology; D005519:Food Preservation / Q000379:methods; D017408:Guidelines as Topic; D006358:Hot Temperature; D041943:Infant Formula / Q000592:standards*
D003470:Culture Media