Not every cup of Coke is created equal. If you're a McDonald's customer who can't resist ordering a large Coke with your Big Mac and fries, you may suspect that the soda from the fast food chain is superior to versions found elsewhere. It's not childhood nostalgia warping your taste buds: McDonald's takes steps to ensure their Coke really does taste better than the competitor's.

Coca-Cola is serious about preserving its secret formula, and the drink you get at McDonald's is made from the same ingredients that you'd get in a can from a vending machine. The difference lies in the way McDonald's treats those ingredients right up to the moment they fill your cup.

Most Coke syrup is shipped to restaurants in plastic bags, but for McDonald's, one of the company's most profitable partners, Coca-Cola sends the product in stainless steel drums. This material is better at preserving the ingredients and keeping them fresh by the time they arrive at their destination.

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The second reason the Coke at McDonald's tastes so good has to do with temperature. Instead of storing water for the soda in the soda fountain like many restaurants do, the chain uses insulated tubes to transport it from the fridge directly to the dispenser when it's ready to be poured. In addition to tasting great, colder liquid is also better at trapping CO2 bubbles and keeping drinks fizzy for longer.

A major difference between the Coke you have at McDonald's and a Coke you might have at home is that the McDonald's soda is nearly always enjoyed with ice and a straw. These are the final elements that make its Coke special. McDonald's knows that Coke will eventually get watered down in a cup filled with ice, and it's tweaked its syrup-to-water ratio to account for this. That means the best sip of Coke may come after your ice has had a few minutes to melt.

Even the straws at McDonald's were engineered to maximize your soda enjoyment. They're slightly wider than regular straws, so that first flavor-packed sip is able to hit more of your tongue at once.

Not everything McDonald's puts out has been as well-received as its Coke. Some of the biggest failures from the company's history include the McD.L.T., the Arch Deluxe, and broccoli-flavored bubblegum.