Although soft drink consumption has steadily declined, IBIS World reports that the average American consumes about 42.2 gallons a year. Soda fans—whether they’re into regular soda or zero-sugar soft drinks—swear that some beverages taste different depending on the container material. But why would a canned Coke’s flavor vary from the same drink in a plastic bottle?
According to All Recipes, the answer is not because of different soda ingredients. Companies use the same recipe for their sodas, regardless of what type of container the product will go in—so a Pepsi in a can has the same ingredients as one in a plastic bottle. But hot temperatures, storage durations, and product age can change a soda’s taste. The materials a container is made of, such as plastic or metal, can have a significant impact as well when it comes to their effect on flavor.
The distinct taste of a canned soda comes from a water-based polymer (or a chemical compound bonded by molecules) inside the product. Manufacturers coat the inside of aluminum cans with the polymer to prevent the soda’s moisture from corroding it; the compound also prevents the drink from tasting like metal. If you think canned sodas tend to be on the subtle side, it’s likely because of the polymer.
Plastic bottles contain a different chemical. As All Recipes reports, scientists believe a compound called acetaldehyde (also known as aldehyde) might be the reason for its unique taste. It doesn’t help that carbon dioxide—which makes soda fizz—can more easily escape a plastic bottle than an aluminum or glass container because plastic is more porous than other materials. This could explain why some people believe soda in plastic bottle containers tastes stale.
If you want the closest thing to a company’s original soda recipe, opt for a glass bottle. Unlike canned and plastic bottles, glass contains no lingering chemicals, so nothing gets into the liquid.
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