When hitting up the deli for a particular type of sandwich meat, you need to check this one thing to determine if your roast ...

Correction, Sept. 10, 2013: Because of an editing error, this post misstated that top round is used for pastrami and that navel is used for roast beef. It’s the other way around. ( Return to the ...

Take beef, for example. How many times have you (if you eat beef) foregone a package of sliced roast beef for a different package because said beef was slightly iridescent?

Iridescent shimmers are easier to spot on darker meats like beef and some pork—so if you’re eating a slice of turkey from the deli, it could be covered in meat rainbows you don’t notice.