American cheese slices: they’re handy, they make a fine grilled cheese, and they fit conveniently in your purse. What’s not to enjoy? Yet Allen noticed something strange while shopping for cheese: the size of each slice varies slightly according to how big a package of cheese you’re buying. Why is that? Update: Now we know why.

Each slice in the 24-pack is 2/3 of an ounce, and each slice in the 16-pack is 3/4 of an ounce. That’s not a huge difference, but it does mean a 10-calorie difference, and maybe one bite less cheese between the different sizes.

It turns out that we’ve covered this before: Kraft’s Velveeta brand does the same thing with its pre-wrapped slices. We contacted Kraft and received the same exact response that they sent when we asked about Velveeta.

The weight of the individual slices in the two packages is slightly different. In a 12 oz. package, which has 16 slices, each slice is .75 oz. or 21g. In a 16 oz. package, which has 24 slices, each slice is .67 oz. or 19g. Because the weight of the individual slices in the 12 oz. package is slightly greater, the calorie count is also slightly higher.

Only that wasn’t the question we asked: we wanted to know why the slices sizes are different between the different packages. We asked “why has it ended up this way?” in a follow-up question, and received no response.

Maybe that’s highly secret information, not to be shared outside of the pasteurized prepared cheese product industry.

Update: Now we know. A Kraft representative explained that the different package sizes are made in different plants, and the slice size variation is due to “manufacturing differences.”

(Thanks to Allen for the original tip!)

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