Microbiological quality of hospital-prepared blenderised tube feeding

Contaminated blenderised tube feeding (BTF) causes numerous infections in patients with deficient immune systems. The microbial quality of BTF should be thoroughly monitored to reduce the risks of microbial agents and prevent food safety problems such as food poisoning and food-borne illnesses. The aim of this study was to survey the contamination rate of BTF samples prepared in the teaching hospitals in Mashhad, Iran.

This study was conducted on 24 samples of BTF prepared in four teaching hospitals in Mashhad city; the samples were collected randomly. Then specific culture media were used for detected and counted Listeria monocytogenes, Salmonella spp., Staphylococcus aureus, Clostridium perfringens, Bacillus cereus, coliforms and Escherichia coli. The final confirmation of the isolates was performed using polymerase chain reaction.

The total bacterial count was determined in the BTF samples and compared with the Food and Drug Administration medical food standards; 91.6% of the samples had 5.2 ± 0.1 log CFU/ml microbial bacterial contamination considering the standard range. The mean prevalence of contamination in these samples was measured for coliforms 4.9 ± 0.17 log CFU/ml, B. cereus 3.6 ± 0.16 log CFU/ml, S. aureus 3.7 ± 0.15 log CFU/ml and C. perfringens 4.7 ± 0.08 log CFU/ml (p < 0.05). Moreover, E. coli 11 (45.8%), Salmonella spp. 9 (37.5%) and L. monocytogenes 17 (70.8%) samples were detected.

Given the high consumption of BTF and the transmission of food contamination to hospitalised patients, it is essential to improve the hygienic conditions at the site of BTF preparation to prevent re-contamination.