By The Metric Maven
Popcorn is a very New World food. It is amazing that in ideal conditions the kernels of unpopped popcorn can be stored almost indefinitely. Corn was first domesticated in Mexico about 9000 years ago. As a young boy, I recall a friend showing me a popcorn pan with a hand-crank on the lid. We were watching an old movie and he wanted to make something special. My friend placed oil into the pan and heated it, he then tossed in a measured amount of popping corn. Normally, at that point one would immediately put the lid on to keep from being splashed if it started popping immediately. He next tossed in some sugar. The handle was part of a wire sweeper that could push the corn around. This was done until the popcorn had finished popping, and for the first time I had popcorn with a sugar coating. At that age it seemed exotic. At that point in my life I gave no thought to how much extra energy was imparted by the introduction of sugar. The agitator was a nice addition. Generally when popping popcorn in a pan one would need to continuously shake the pan forward and backward to keep the popcorn from burning. Popping popcorn at home was an acquired skill. Popcorn balls (generally colored in some fashion) were often handed out at Halloween in my small town as a treat. The largest documented popcorn ball is 2.4 meters in diameter, 7.5 meters in circumference, with a mass of 1549 Kilograms (well over a Megagram). Popcorn was also strung on thread to decorate Christmas trees during the winter holiday season.
In China and Korea a sealed cast-iron canister with popcorn inside is used like a rotisserie over a fire. When a pressure gauge on the container reaches a threshold value, the canister is taken from the flame, a canvas sack placed over the top and the seal broken. With a large boom, the popcorn explodes all at once. It is then poured into the canvas bag.
The first popcorn was popped by hand (sometimes over an open fire), and was later automated with steam powered mechanisms designed in the late 19th century. This new popcorn popper was introduced at the 1893 Colombian Exposition. When I was a boy we purchased sealed plastic bags of popcorn kernels with Jolly Time printed onto the transparent film. The big change in popcorn preparation came when General Mills obtained the first patent for bagged microwave popcorn in 1981. This made popping popcorn much more convenient and a surge in popcorn consumption followed. People also ceased to see popcorn kernels any longer as they now come in an opaque bag.
Microwave popcorn allows one to eat popcorn with a very consistent serving size in terms of mass and volume. This consistency would be great for those who are trying to monitor their food energy intake. When I first attempted to determine the energy content of popcorn I was very surprised at the low value. The serving size per bag is about 3 and the serving size is 1 cup popped or three cups. This works out to 90 Calories (377 KJ). My significant other (SO) immediately doubted this value. It had to be higher. In recent years it has been emphasized that we should go back to Olde English only nutrition labels. One can see this from the nutrition labels that Ye Olde English is still Kyng. Here is the nutrition label for Pop Secret’s Homestyle Microwave Popcorn:
So if the servings per bag is about three, and the serving size is two tablespoons unpopped, then it would be a total of 3*150 Calories or 450 Calories (1884 KJ). The fact that the serving size is given as 2 tablespoons unpopped and 1 cup popped seems to indicate an equivalence. So which is it? Ninety Calories per bag or 450 Calories per bag? This difference is a factor of five! The range given on the web for a single bag of Pop Secret Homestyle was from around 400-500 Calories or so. When I looked at the bag after popping, and used my 100 mm wide hand to measure it, the bag appeared to be somewhere around two liters in volume, but I had no idea how many cups that might be. I could immediately estimate the value in metric, but could not do the same with Ye Olde English. My SO and myself then conducted an experiment, we popped a bag and measured it with a one cup measure. It turned out to be somewhere from about 10-12 cups of popped popcorn. It would seem that each bag contains about 6 tablespoons of unpopped popcorn, and 15 cups when popped, but the nutrition label does not say that.
When converted to metric the clarity has not increased much:
Serving Size 15 mL unpopped 237 mL popped
Amount 15 mL 237 mL
Per Serving Unpopped Popped
Calories 150 30
So 15 mL of popcorn becomes about half of a 500 mL bottle of soda or water. Does that make sense or not? I was able to estimate the volume of a popped bag at about two liters or 2000 mL. Given about 200 mL per serving 2 liters would be about ten servings or 300 Calories. Clearly the value would not be 90 Calories.
In my view this label has been designed to confuse. Who eats unpopped popcorn? Who even sees the unpopped popcorn in a sealed opaque paper bag? How would you estimate the unpopped amount when you can’t even see it! One would immediately look at the label assume 3 cups per bag at 30 Calories per cup and compute 90 Calories total. There have been moves to go back to Ye Olde English from metric for US nutrition labels to make them more “understandable.” The Pop Secret label is unclear in metric and even more inaccessible in Ye Olde English. It could have been written:
Calories per bag: 450
Servings per bag: 3
Calories per serving 150.
Calories per cup 30
Volume of bag: approximately 2500 mL
The nutrition label as it is originally formatted appears to be designed to mislead consumers into believing that microwave popcorn contains far less calories than it does. This in turn causes the person to consume more calories and hence more product while blowing their estimated food energy intake.
Profiting from measurement confusion and misinterpretation is often thought to be a thing of the past. It is clearly not—and never has been. I have a measuring scoop provided inside my laundry detergent box which has a volume twice that recommended for each wash. It has a line halfway up its side which is the recommended volume. People don’t notice the transparent line, or read the tiny instructions, and generally fill the scoop up to the top, using twice the recommended amount of soap. People who see the importance of implementing the metric system, and the teaching of basic numeracy as fringe issues in the United States, are but ignorant marks for our modern industrialized hucksters.
The Metric Maven has published a new book titled The Dimensions of The Cosmos. It examines the basic quantities of the world from yocto to Yotta with a mixture of scientific anecdotes and may be purchased here.