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How To Reheat Coffee In Microwave

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Whether you pour fresh-brewed coffee into an insulated tumbler, ceramic mug or glass cup, the hot beverage will eventually cool down. Room temperature coffee doesn’t taste nearly as good, so how do you reheat coffee in microwave?

From americano to creamy and sweet lattes, starting the morning with your favorite cup of coffee is a normal daily routine for many people. But sipping on lukewarm java is definitely not as pleasant as a steamy hot cup of joe.

Always use microwave-safe mug instead of paper or styrofoam cups. Start with half-filled cup, adjust the power level to medium-high, and nuke for about 45 seconds. If it is still warm, continue to microwave using 30-second increments until the liquid reaches your desired temperature. 

If you are reviving old black coffee in the microwave, you may experience a more bitter taste. Simply add a splash of creamer, milk for coffee, or sweetener to remove bitterness from the reheated coffee. 

Can you Heat Up Coffee in the Microwave?

Microwave is easiest way to reheat food and beverages in a short amount of time; heating up coffee is not an exception!

You may heat up coffee to increase temperature to your desired warmth. However, heating up coffee might affect the flavor by making the beverage taste slightly bitter. 

When coffee cools, chemical components change and the acidity level increases in the beverage. So, reheating coffee with sudden heat increases the breakdown of aromatic flavors, which results in an acidic taste. 

Not every cup of coffee is reheated the same way. Here are the best ways to heat up coffee in the microwave based on specific brands and serving methods:

  • Starbucks: Starbucks sells specialty coffee drinks in reusable containers like plastic cups and glass bottles. The only microwave-safe container is the ceramic mug. Make sure to test it out and heat 30 second durations to find the desired temperature. Store fresh brewed coffee in Starbucks tumbler. If it is double-wall vacuum-sealed then it is best to avoid using it in the microwave. 
  • McDonald’s: Unfortunately, McDonald’s coffee cups are glued together along the side seams with plastic and wax coating. As a result, they are not microwave-safe because the adhesive layer may melt and leach into the hot coffee. 
  • Dunkin Donuts: Dunkin Donuts coffee beverages used to serve in coffee in styrofoam cups to keep the hot drinks hot for longer periods of time. But in recent years, they developed double-wall paper cups for an environment friendly disposable product. 

If you are using the microwave to revive a lukewarm coffee drinks, make sure to double check if the cup is microwave safe. As it turns out, most to-go cups are not safe to use in the microwave. 

Is it Bad to Microwave Coffee?

Microwaving coffee does change the flavor and taste, but there are no correlations between the consumption of reheated coffee and harmful health concerns. 

However, reheating coffee in paper or plastic cups that are not microwave-safe will leach glue, plastic and wax compounds into the hot beverages, which is something you would need to avoid. 

Microwaves use electromagnetic radiation, and the effects on liquid is not harmful unless there is metal, plastic or styrofoam inside the kitchen appliance. 

Heating a cup of coffee in the microwave agitates the water molecules, which makes the atoms move faster and cause friction that generates heat. The electromagnetic radiation will not fundamentally change the liquid into a harmful structure, but what exactly happens to coffee when microwaved?

What Happens

Before you microwave a cup of coffee, learn more about what happens to coffee while being heated. 

According to the study, not only does coffee have caffeine, but it also consists of over 1,000 different chemical compounds. That is why all coffee beans have different flavor profiles.

The flavor of coffee is affected by the growing climate, soil conditions, when the beans were harvested, and also how the beans were dried, stored, and roasted. There are many variables and steps that can affect the aromatic compounds in a positive or negative way. 

When you microwave coffee, the heat waves breakdown any aromas that are left from the fresh brewed coffee. In this case, the aroma doesn’t only means smell, but also the sour, salty, bitter, and sweet taste. The disintegration of aromas eventually alter the flavor and make your coffee taste stale. 

Caffeine is considered one of the most important elements of coffee because it keeps us alert and awake at the start of the day. When microwaving coffee, do you think reheating reduces the amount of caffeine? 

Does Microwaving Coffee Remove Caffeine?

Caffeine is a large, heavy, and non-volatile molecule that won’t lose its property very quickly. Even though you may experience a change in taste because the cold coffee comes in contact with oxygen, reheating in the microwave does not destroy the caffeine. 

No matter when the coffee was prepared, caffeine does not evaporate or disappear after microwaving. The amount of caffeine in your coffee stays the same between five minutes and five hours. However, there will be slightly more caffeine due to water evaporation that increases concentration of caffeine in the reheated coffee.

The only way to remove caffeine from coffee is by processing green coffee beans. There are three ways to decaffeinate coffee, but each approach uses green or roasted beans to moistened caffeine so it can be drawn out.

That being said, simply microwaving coffee won’t cause caffeine to disappear in the reheating process. Caffeine can only be removed before the roasting and grounding of the finished coffee beans. 

Things to Know

Whether you are reheating homemade coffee or leftovers from Starbucks, there are essential things you need to know before microwaving coffee.

Instead of brewing brand new cup of coffee or running to the store to get new one, microwaving cold coffee is quick solution to give you a caffeine boost.

However, reheating coffee in any way can affect the flavorful aromas and possibly make the java taste bitter. Counteract this by adding a splash of your favorite creamer and sweetener.

Best way to reheat coffee in the microwave:

  • Use microwave-safe cup. 
  • If the cup is not labeled for microwave use, test the cup by adding filling halfway with water and nuke for 30 seconds. If the water is hotter than the cup, then it is considered to be microwave-safe.
  • If you are at all uncertain, transfer the coffee into a microwave-safe mug before reheating.
  • Avoid putting lid on tightly while microwaving. It may melt, superheat or explode while air is trapped inside the container.
  • Use medium power level to reheat in the microwave.
  • Stop and stir enough every 30 seconds to evenly distribute the temperature.
  • Store leftover coffee or lattes in the fridge to avoid any mold or spoiling of the dairy inside the beverage. 

From early morning to midday, coffee is a fan favorite that many people simply can’t live without. For best results, reheat coffee in microwave on a medium power setting and slowly increase temperature instead of rushing with high heat that can burn or scald the coffee flavor.

Best way to reheat coffee in the microwave

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