Document Type: Original Articles


1 Department of Nutrition, School of Nutrition and Food Sciences, Shiraz University of Medical Sciences, Shiraz, Iran

2 Department of Food Hygiene and Public Health, School of Veterinary Medicine, Shiraz University, Shiraz, Iran

3 Department of Food Hygiene and Quality Control, School of Nutrition and Food Sciences, Nutrition and Food Sciences Research Center, Shiraz University of Medical Sciences, Shiraz, Iran


Background: Although enteral feeding solutions are used to reduce the morbidity and mortality in many malnourished and hospitalized patients, microbial contamination of these products may lead to severe infections, especially in immune suppressed ones. The aim of this study was to evaluate the microbiological quality of commercial enteral feedings in two hospital settings in Shiraz. Methods: Twenty commercial enteral feedings were collected immediately after preparation and then homogenized and serially diluted on the same day. MPN methods were used to evaluate the total viable count and Escherichia coli count. They were also tested for total coliform (pour plate method) and the presence of coagulase positive staphylococci. The results were compared with standard limits. Results: All samples had a total viable count lower than 104 colony forming units (CFU) per g (the maximum recommended level of FDA standard).For all enteral feedings, coliform counts were not detectable (<10 CFU/g).Escherichia coli counts were also lower than those of Brazilian legislation (<3 CFU/g). Coagulase positive staphylococci were recovered just from one sample (5%). Conclusion: Freshly prepared commercial enteral feeding samples h ad a cceptable m icrobial q uality. S uch p roducts are considered to be more acceptable than hospital prepared ones. However, further steps involved in the preparation and administration of commercial feedings can be sources of microbial contamination. Thus implementation of hygienic practices and monitoring procedures during preparation and administration can be suggested.


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