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Top 10 Groceries Americans Buy

Packaged Meats

Deli meats -- precooked or cured meats like roast beef, salami or bologna -- are easy fillings for sandwiches and offer a quick meal option. After all, what's easier than stepping up to the deli counter?

Well, if you're buying sliced meat, it's seeing the rainbow. Wacky as it sounds, lunch meat (which is the compressed end product of several cuts of meat and filler) or sliced cooked beef (which probably still has filler) will show all the colors of the rainbow if sunlight bounces off the meat at just the right angle. That's because the pigments in meat compounds, such as iron or fat, can give off colors -- even green -- you may not expect to see in meat that's not past its expiration date.