Use the small hole in your coffee bag to determine how fresh the beans are.

Here we’ll explain why.

That chemical reaction creates a lot of carbon dioxide.

Close-Up Of Hand Holding Coffee Beans Growing On Tree

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The degassing doesn’t happen all at once.

When coffee beans are bagged shortly after roasting, they’ll continue releasing carbon dioxide inside their packaging.

The valve helps you determine which bag of coffee to buy.

Fresh Roasted Coffee Beans With A Black Cup And A White Paper Bag with Degassing Valve On Wooden Table

Getty Images.Credit: Getty Images

Coffee in Cans vs. in Bags

Coffee in cans is different.

As you’ve noticed, cans don’t usually have a valve or hole.

The difference is simple.