I ALWAYS have emergency food in my truck as part of my overall 72 hour emergency kit. Your vehicle is a logical place to keep extra food, especially since we spend so much time there (commuting, traveling, etc..).
A problem with storing food in a vehicle though is this — the shelf life of stored food will be reduced when it’s in an environment that is HOT (e.g. in a vehicle during the summer time).
In fact, for every 10 degrees C (18 degrees F) of temperature rise, the shelf life of food will generally be cut in half.
Temperature vs. Food Storage
The following is this year’s reminder to rotate out your summer food from your vehicle:
An example of food shelf life deterioration in a vehicle over the length of a hot summer:
Most food with a stamped date on the packaging is referring to a ‘Use-by’ or ‘Best-by’ date. First of all, these dates are NOT the date at which a food will ‘go bad’ (refer to the linked article for an explanation). With that said, and for the sake of food rotation, lets suppose that this date is your objective…
Let’s say you have food bars in your vehicle and the stamped ‘use-by’ date is one year beyond the date of manufacture…
Note: Most all shelf life references are to ‘room temperature’, let’s say 72 degrees F.
According to the National Highway Traffic Safety Administration, when outside temperatures are between 80° F – 100° F (27° C – 38° C), vehicles parked in direct sunlight can reach internal temperatures up to 131° F – 172° F (55° C – 78° C).
If the temperature in the vehicle was 150 degrees for the entire time period, the food shelf life which was originally one year would be reduced to about 20 days!
The reality is that the average temperature inside the vehicle will not be 150 degrees! Cooler temperatures during night, the time it takes for the internal temperature to rise and fall, being parked in the shade, your actual local weather, etc., will affect the actual real affect of shelf life reduction (considerably less damaging than the example above), however you get the idea…
Let’s say the average temperature inside your vehicle throughout the summer is 90 degrees. That will cut your shelf life in half. So, simply rotate out those foods (don’t throw them out – just consume them).
72° (1 year shelf life)
90° (72°+18°) (182 days shelf life)
108° (90°+18°) (91 days shelf life)
126° (108°+18°) (46 days shelf life)
144° (126°+18°) (23 days shelf life)
It’s the end of summer, so this is your updated reminder to check the foods stored in your vehicle. Oh, and by the way, if you don’t have any food stored there – you should!