Bacterial Safety of Commercial and Handmade Enteral Feeds in an Iranian Teaching Hospital

Abstract

Background: This study aimed to investigate and compare the bacterial safety of handmade and commercial ready‑to‑use enteral feeding formulas used in an Iranian teaching hospital.

Methods: In this experimental study, a total number of 70 samples (21 handmade formulas sampled at two sampling times, i.e. the time of preparation and 18 h after preparation, and 28 commercial ready‑to‑use formulas) were studied. Total count of viable microorganisms, coliform count and Staphylococcus aureus count for all samples were conducted.

Results: Out of 42 handmade samples, 16 samples (76%) had total viable counts greater than 103 CFU/g in the first sampling time and 17 samples (81%) had total viable counts greater than 103 CFU/g in the second sampling time. Also, 11 (52%) had coliform contamination in the first sampling time which reached 76% (16 samples) in the second sampling time. Regarding contamination with S. aureus, 5 samples (24%) were contaminated in the first‑ and 13 samples (62%) were contaminated in the second‑sampling time. Out of 28 commercial formulas, 27 samples (96%) had total viable counts greater than 103 CFU/g. Also, 24 samples (86%) were contaminated with S. aureus and 27 samples (96%) were contaminated with coliforms. In order to compare these two formulas, the results of Mann‑Whitney test showed that contamination of ready‑to‑use formulas in all three microbiological samples was significantly more than that for handmade samples.

Conclusions: The results of the present study indicate that the microbial safety of enteral feeding solutions in this hospital is much lower than standard values, demonstrating that the development of protocols for clean techniques in the preparation, handling and storage of both commercial and handmade enteral feeds is necessary.

Keywords: Bacterial contamination, enteral feeding, handmade formulas, microbiological safety, ready‑to‑use formulas