Are McDonald's eggs real? Fast food giant cracks mystery

If it looks like an egg and tastes like an egg…Is it really an egg?

To crack this mystery for customers, McDonald's enlisted former MythBusters star Grant Imahara to shed some light on its egg production process as part of the fast food giant's latest video to boost food transparency.

Imahara traveled to Herbruck's Poultry Ranch, an egg supplier for McDonald's U.S. unit, to find out more with a McDonald's blogger.

First eggs that were laid within the past day travel on a conveyor belt, said Harry Herbruck, the supplier's executive vice president of operations. Some arrive from a chicken house as little as 100 feet away.

"Many of these eggs are so fresh that if you picked them up, they'd still be warm," Herbuck added.

They're then washed, dried, inspected for cleanliness and weighed. Eggs that are too big or small for the whole eggs used in Egg McMuffins will be used instead as liquid eggs for other menu items.

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The supplier then sends light through the eggs to find imperfections and discards defective eggs.

The McMuffin-sized eggs are then packed into egg cartons, where they're then cooled and shipped in trucks to distribution centers. Restaurants crack these whole eggs to make Egg McMuffins.

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The too-big and small eggs are broken, chilled to prevent bacteria growth, transported to a holding silo and then put it a tanker that go to Cargill, another McDonald's supplier.

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The video does not mention what other ingredients go into the eggs used in different menu items.

For example, its scrambled egg includes sodium acid pyrophosphate, citric acid and monosodium phosphate to preserve the egg's color and a separate preservative, according to McDonald's website.

Meanwhile, its folded eggs ingredient list with items used to enhance the color, texture and flavor is long too: "pasteurized whole eggs, modified food starch, soybean oil, natural flavors (plant source), sodium acid pyrophosphate, carrageenan, flavor enhancer (salt, maltodextrin, natural flavor [plant source], spices, herb, turmeric [color]), monosodium phosphate, citric acid, soy lecithin."

In a separate post on its site, McDonald's answers another common fast-food question: whether its eggs are microwaved or grilled before serving. The answer? It depends.

The chain uses the grill for its folded eggs, scrambled eggs, egg whites and freshly cracked eggs. It does microwave the eggs used in its sausage burritos that have been previously cooked in its suppliers' kitchens.