Cooling properties of everyday liquids.

OBJECTIVE: To examine the cooling properties of a variety of 'everyday' hot liquids within the context of scald injuries in the United Kingdom. METHODS: The temperature of common hot liquids, including water, tea, coffee and various other liquids (i.e. takeaway coffees, "Indian tea", chicken curries, hot milk and oil) were recorded over a time period, using digital cooking thermometers. RESULTS: Minimal difference was detected between the cooling rates of hot water, coffee and tea. Indian tea cooled at a slower rate. The speed at which milk cooled was less than other liquids and the higher the fat content the slower it cooled. Takeaway beverages had a lower starting temperature and retained heat for substantially longer periods. The assessment of cooking oil revealed intense heat production and prolonged cooling. CONCLUSION: The authors propose that if a patient is exposed to a 'common' scalding agent that has been cooling for 10 min or less then the temperature of that fluid is likely to be greater than 60°C and therefore capable of causing a burn within seconds of exposure. Furthermore, most liquids tested take between 15 and 30 min to reach a "safe temperature" below 53°C.