Enterobacteriaceae, cronobacter (enterobacter) sakazakii and microbial population of infant formula products in the market

Abstract

This study was carried out to detect and identify the presence of Cronobacter (Enterobacter) sakazakii, Enterobacteriaceae and microbial population of infant formula products which were obtained randomly from hypermarkets and private hospital in Ampang area. Samples that were analyzed included 16 infant formulas (RB 1 - RB 16) and 14 special infant formulas (RB 17 - RB 30) from eight manufacturers. A total of/ire samples (RB 11, 13, 18, 19 and 29) failed to comply with the microbiological criteria for aerobic colony count as stated in the Malaysian Food Act 1983 and CAe. The infant formula and special infant formula samples with different ingredients and nutrient composition did not show any significant difference in terms of aerobic plate count. For the identification of Enterobacteriaceae, Klebsiella pneumoniae spp. pneumoniae, E cloacae, E. amnigenus, E. asburiae and Pantoea spp. 3 were detected in seven samples after confirmation using ID 32?? biochemical test (Biomerieux). Although no C. saka:akil positive samples were detected after the confirmatory test, but some strains of E amnigenus, E. cloacae and K. pneumoniae spp. pneumoniae were found to give false positive results on DFI agar while some strains of E. cloacae, K. planticola and K pneumoniae spp.pneumoniae gave false positive results on C??S agar.