Optimal hang time of enteral formula at standard room temperature and high temperature.

Background: Despite high risk of bacterial contamination, yet there are no studies that have evaluated the optimal hang time of blenderized and reconstituted powdered formulas at standard room temperature and high temperature.

Aim: To investigate the optimal hang time of both types of formulas at standard room temperature and high temperature.

Methods: Ten specimens of blenderized formula and 10 specimens of reconstituted powdered formula were prepared using aseptic techniques. Five specimens of each formula were administered at 25 °C and 32 °C. Simulated administration was done in an incubator. The samples were collected at 0, 2, 4, 6 h and aerobic culture was performed. Food and drug administration criteria were used to determine the unacceptable levels of bacterial contamination.

Results: Unacceptable contamination for blenderized formula began at 4 h at 25 °C and at 2 h at 32 °C. As for the reconstituted powdered formula, there was no bacterial growth in all specimens up to 6 h at both temperatures.

Conclusion: The optimal hang time to avoid significant bacterial contamination of the blenderized formula should be limited to 2 h at standard room temperature and be administered by bolus method at high temperature, while a reconstituted powdered formula may hang up to 6 h at both temperatures.