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Can You Microwave A Starbucks Plastic Cup?

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Tired of sipping on cold coffee leftover from this morning? If you want to know if it is safe to microwave a Starbucks plastic cup, then you are in the right place.

Coffee is generally served hot, so it seems instinctive to want to microwave Starbucks cups. As with most things in life, there is a right way and a wrong way, so can you microwave a Starbucks plastic cup? 

Plastic cups from Starbucks are designed to hold cold beverage like an iced tea or blended Frappuccino. It is not safe to microwave Starbucks plastic cups, therefore it is recommended to stick with using ceramic or glass containers that are labeled as “microwave safe.”

So how do you reheat coffee in the microwave? Let’s review safer options to avoid using a Starbucks plastic cup in the microwave.

Are Starbucks plastic cups safe?

Plastic cups are recognized as a single use and disposable containers that have become readily available for grab and go customers. Not only are they convenient and plentiful, but they are also cheap and lightweight.

The downside of using plastic cup is that it is ineffective at keeping a cup of coffee hot. Due to the construction of the cup, the thin walls require a sleeve to comfortably hold the hot drinks and keep the heat from dissipating away quickly.

The reusable plastic cups from Starbucks can last a long time when used to serve cold beverages, up to 30 uses. However, the most common issue is that the lid warps from high heat and no longer snaps into place properly on the top. 

There are several types of plastic coffee cups and many of them are designed for safe use in the microwave. However, specification really depends on the type of plastic used to make the cup. 

It is fair to say that drinking from a plastic cup is not really safe, let alone using it to heat in the microwave. Heat makes things even worse by degrading the plastic, therefore dishwashing and microwaving plastic Starbucks cups is not recommended.

In general, plastic coffee cups are not meant to hold warm or hot liquids. Starbucks plastic cups are made from polypropylene, and only 5.1 percent from recycled materials.

When plastic is heated, the risk of contamination from leached chemicals is 55 times faster than the normal rate. To-go plastic cups from Starbucks are BPA free, but there is still an inherent risk when using soft plastic polymers.

Before microwaving a plastic Starbucks cup, consider transferring your beverage into a glass or ceramic cup. Not only can you avoid using a paper sleeve to hold the cup, but you don’t have to worry about the plastic compounds leaching into your hot beverage.

Are plastic coffee cups microwave safe?

Not every plastic cup is safe for microwave use. You should only use plastic cups that has been specifically labeled as microwave safe. 

Check the bottom of the cup for a number or microwave safe symbol. If the cup has a #5, it is made from polypropylene, PP, which is generally considered microwave safe.

PP plastic is known for being durable and heat resilient because the plastic feels cool after being microwaved. 

  • 1, 2, 4 are sometimes microwave safe
  • 3, 6, 7 are not microwave safe

In order to figure out if a plastic coffee cup is microwave safe or not, review these guidelines to help you find out:

  • Fill a cup half full of water.
  • Microwave for one minute with the liquid inside. 
  • Cautiously feel the cup to determine the temperature.
  • If the plastic cup is warm or hot after heating, it is not microwave safe. 
  • If the plastic cup is cool, and the liquid inside is hot, it is considered microwave safe. 

Plastic is not always safe to use in the microwave. Some plastic cups are thin, and can melt or release plastic chemicals into the beverage. 

Things to know before microwaving Starbucks plastic cups

To further avert the risks for further use, continue reading the helpful tips to determine if plastic cups from Starbucks are microwave-safe. Understand these tips before using a microwave to heat up your beverage inside a plastic cup.

There are ways to to test and determine if a plastic cup is suitable to enter microwave:

  • Check the recycling symbol marked on the bottom. 
  • Avoid plastics with the numbers 3, 6 or 7. 
  • The safer plastic cups are labeled as 1, 2, 4 and 5. 
  • Make sure to look for the numbering system before proceeding with serving food in just any type of plastic. 
  • Skip heating food and beverages in plastic cups, and instead use glass or microwave-safe cups. 
  • The natural materials are dense, which helps to transfer heat molecules quick and smooth way without melting and damaging the original cup.

Reusing Starbucks plastic cup is convenient when it comes to serving cold coffee, however they are not guaranteed safe for microwave use. Look for the plastic number on the bottom and test the cup for yourself to determine if it is microwave-safe.

Best way to microwave a Starbucks plastic cup

If you have no other options and you find yourself using a plastic cup in the microwave, then proceed with caution.

Here is the best way to heat up a plastic Starbucks cup in the microwave:

  • Start with a medium power level instead of the default high setting when heating liquid in microwave-safe cups.
  • Use 30 seconds increments.
  • Test the contents to determine if the desired temperature is reached.
  • Stir the contains of the plastic cup.
  • Microwave for another 30 second duration, stir and check again.

If you have been using a plastic cup from Starbucks in the microwave without any problems, then you have no concerns and continue to proceed with caution. However, if you question the safety of microwaving a Starbucks plastic cup, then consider using a microwave-safe cup or mug to reheat and keep beverages hot for longer periods of time. 

Is it safe to microwave a Starbucks plastic cup
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