There’s nothing more refreshing than an ice-cold drink on a hot day, and thanks to koozies, you can always count on that cool beverage. It’s the perfect companion for a hot summer’s day!

Let’s dive into the science and even do an experiment to see why a koozie is able to keep your drink cold!

What is a Koozie?

A koozie is a sleeve made of fabric such as foam or rubber that slides on to the bottom of a 12-ounce can or bottle. The purpose of a koozie is to insulate the drink container to keep it cold.

A koozie can also go by the following names:

  • Huggie
  • Beer jacket
  • Bottle jacket
  • Can holder
  • Coozies
  • Coasties
  • Can cooler
  • Beer hugger
  • Cozy
  • Coosie
  • Coldy-holdy
  • Coolie
  • Beer sleeve

Regardless of what you call them or what material they’re made of, koozies keep your drinks cold even on the hottest summer days!

How Does a Koozie Keep Drinks Cold?

A koozie keeps your drinks cold by preventing condensation from forming on the can or bottle. Condensation forms when moist humid air meets a colder surface like your drink! A koozie acts as a barrier to prevent condensation from forming.

On a hot, humid day, your canned drink will form water droplets of condensation on the outside. The hotter and more humid the weather, the more condensation you’ll see on the can or bottle.

The condensation on the can warms up from the surrounding air, which in turn warms the beverage inside! When you put a koozie on your drink, it prevents condensation from forming and keeps your drink colder for longer.

If you’re outside for just 5 minutes in Phoenix, your drink’s temperature can increase by 6 degrees. In New Orleans, it would go up 12 degrees at the same temperature in the same amount of time because of the humidity!

What Does a Koozie Do?

A koozie is more than just a fashion statement for your canned or bottled beverage. This drink holder serves several benefits such as:

  • Prevents your hands from getting cold
  • Avoids water rings on tables
  • Insulates your drink
  • Keeps condensation off your drink

Koozies Prevent Your Hands from Getting Cold

Trying to do anything when your hands are cold is no fun! Cold hands can cause discomfort, stiff joints, and even numbness or tingling. When you pull a canned or bottled beverage from an ice-cold cooler, slip a koozie on it to protect your hands.

Koozies Stop Your Drink from Leaving Water Rings

When condensation forms on your drink, it can drip down and leave a ring of water on the table underneath. A water ring can damage surfaces like wood, but a koozie can prevent condensation from pooling up on the table. Think of a koozie acting like a coaster!

Koozies Insulate Your Drink

Did you know the normal temperature of your skin is 91 degrees? Wrapping your warm hand around your drink could speed up the warming process! Luckily, a koozie acts as a barrier between your warm hand and the cold drink.

Koozies Keep Condensation Off Your Drink

You don’t want to keep wiping off your wet hand after you take a sip from your cold drink. A koozie helps keep your hands dry and your drink cold by keeping condensation off the can or bottle.

Why Does Preventing Condensation on a Bottle Keep it Cool?

When water droplets form on the outside of your can or bottle, the surrounding air warms the droplets and makes your drink warmer as a result! A koozie prevents condensation from forming and keeps your drink cooler for longer.

A koozie makes enjoying a cold drink that much better. You won’t have to worry about your hand getting cold, leaving water rings, or annoying condensation. Once you start using a koozie, you’ll never want to be without one, whether you’re going to a concert, the beach, or enjoying a night in!

What Type of Koozie Works Best?

Koozies are commonly made in a variety of materials that keep your drinks cold at different rates. Generally speaking, rubber, neoprene, and polyurethane koozies work best because they are the most effective at insulating a cold beverage.

In order to figure out which type of koozie works best, we tested out four different materials: polyurethane, rubber, foam, and neoprene. Our experiment was conducted using the following steps:

Step 1

Five 12-ounce cans were removed from the refrigerator and a different koozie was placed on four of the five cans. The koozies were made of different materials including polyurethane, rubber, foam, and neoprene.

Step 2

An initial temperature was taken for each can.

Step 3

The cans were left out in a room-temperature environment for one hour.

Step 4

The temperature for all five cans was taken again.

Once all the results were gathered, the end temperature and start temperature were subtracted to see how cold the drinks stayed over time. There were two koozies that kept the drink cooler than the rest: rubber and neoprene! Both koozies only increased the temperature of the beverage by 16 degrees over the course of an hour.

Here’s how all five cans compared to one another:

Polyurethane came in a close second with only a 17 degree increase, and foam was the least effective koozie material. Overall, any koozie will keep your drink colder compared to no koozie at all!

See our koozie experiment in action by watching this video!

How Long Does a Koozie Keep Your Drink Cold?

A koozie will keep your drink cold anywhere between 30 to 60 minutes. That number ultimately depends on whether you’re in a room temperature environment or if you’re outside on a hot day. You can always add ice to your drink or keep it in the shade to help it stay cold on hot summer days!

The Bottom Line

Koozies work against the forces of the atmosphere to keep your drink extra cold on the hottest day. Without them, we would be doomed to water rings and damaged tables. Next time you’re heading out on a hot summer day, be sure to slide a koozie over your drink. You’ll thank us later!

References

Farzana, Abanty. (2001). Temperature of a Healthy Human (Skin Temperature). Retrieved January 21, 2020, from
https://hypertextbook.com/facts/2001/AbantyFarzana.shtml

Elliot, Mark. (2017, July 28). Science Behind the Koozie. Retrieved January 21, 2020, from
https://www.craftbeer.com/craft-beer-muses/science-behind-beer-koozie

Welsh, Jennifer. (2014, August 29). Science Proves It: Koozies Keep Beer Colder. Retrieved January 21, 2020, from
https://www.businessinsider.com/koozies-stop-condensation-and-keep-beer-colder-2014-8

Michaels, Jay. (2017, October 31). The Perfect Serving Temperatures for Your Favorite Drinks. Retrieved January 22, 2020, from
https://drinkfridge.com/serving-temperatures-favorite-drinks/

About the author

Gianna Petan

Gianna is no stranger to all things promo products. Her background in research-based writing, linguistics, and advertising gives her an edge in blogging about the marketing industry.