Moreover, IR thermometers can be used to safely measure food items without touching them. That greatly reduces cross-contamination, or even eliminates it if the proper temperature measurement techniques are strictly and properly practiced. IR thermometers can also be used to measure hot, hazardous, or hard-to-reach surfaces without damaging them or the user getting burned. That is particularly beneficial when food service workers are measuring temperatures of dangerous items such as hot fry oils and candy.
Measuring Surface Temperatures
While IR sounds like the perfect total temperature measurement solution, in most people’s minds it has always had one major drawback—it only measures surface temperatures. What about the internal temperature of items such as soup, salsa, and macaroni and cheese?
Typically, food service operators love the speed and convenience of IR but don’t fully embrace it because they need the safety of an internal temperature. But, as they learn more about how to use IR to its full potential, its perceived limitations begin to disappear.
Using IR with NSF Rules
Under National Science Foundation (NSF) rules 4 and 7, temperatures must be taken 1 inch below the surface of the food item. In most people’s minds, that rules out using IR. They believe they need a probe thermometer to reach that critical 1 inch below the surface. A probe thermometer is one way to get that 1-inch below the surface temperature, but IR can also be used to take that internal temperature. Here’s how:
To measure cold food lines, use the serving spoon to move the top of each food item aside 1 inch to reach the new food surface. Immediately scan within a half inch of the food item with the IR thermometer. If the item is in the safe zone (below 40° F (4.4° C)), move to the next item. If not, take appropriate action to ensure the food item’s safety.
Likewise, for hot foods, use a ladle to pull food up from 1 inch below the surface and shoot the IR thermometer in close—within a half inch of the newly uncovered surface to get an instant and accurate internal temperature. With this method, cross contamination concerns disappear because none of the food has been touched by the operator or the thermometer.
Range of Features
Expanding the use of IR technology in the food service industry has included working to educate the industry about the breadth of this technology. There are more and more IR products on the market including some that combine IR with a traditional probe thermometer. Some models have a built in timer with an alarm that sounds when the next line check is due, and HACCP lights that flash red when a food item is in the unsafe zone and green when it is okay to serve the food. In addition, some models come with full two-year warranties for normal use failure, including dropping and calibration. Some are also NSF approved.
In his report to his military client, quality control consultant Niemeyer details all the advantages that IR offered during his evaluation, which included:
Response Time: Almost immediate, allowing user to complete and record line (holding) temperatures on HACCP risk management forms more rapidly, thereby greatly reducing interference with line servers.
Grill Surfaces: IR feature is extremely useful and easy—avoids having to reach around cooks to place surface thermometer on grill, records temperatures at two or more areas of the same grill instantly to check calibration and especially useful when products require different settings such as scrambled eggs cooking along side hash browns. Almost guarantees proper cooking procedure.
Ambient Temperatures: IR feature is very accurate and fast for use in walk-in refrigerators and freezers to quickly check various parts of the food storage units and temperatures of items within the freezers where probes are useless.