Temperature Profiling of Household Refrigerators in Scotland Using a Citizen Science Approach

A citizen science survey was conducted in Scotland to assess domestic refrigerator temperatures in 361 households using temperature data loggers placed on the top and bottom shelves. The mean refrigerator temperature was 5.17 °C, with household averages ranging from -0.39 °C to 10.94 °C. More than half of refrigerators monitored (55.4%) operated above the recommended operating temperature (0-5 °C). Top shelves were significantly warmer than bottom shelves (5.89 °C versus 4.45 °C, respectively). Twenty-seven refrigerators (7.5%) never recorded temperatures within the recommended temperature range during the trial, with all observations >5 °C. Refrigerator age, household size, and household age composition (e.g. houses with young children) were not associated with a change in refrigerator temperature; however, the type of refrigerator significantly influenced the average temperature, with American-style/larder refrigerators and free-standing models operating at lower temperatures. Most participants did not routinely check their refrigerator temperatures; however, refrigerators with temperature alarms were associated with significantly lower temperatures, suggesting the potential for these features in helping consumers ensure their refrigerator is operating in the correct temperature range. Improved awareness of the importance of monitoring refrigerator temperatures may help to reduce foodborne illness risk for consumers.