Can You Put Styrofoam in the Oven?

Can styrofoam go in the oven? This is a million-dollar question most people ask. While you might be tempted to reheat your leftovers in the oven, it still helps to know whether or not styrofoam is considered oven-safe. Styrofoam is microwave-safe, but is it oven-safe? Let’s find out if styrofoam can safely go into the oven to play your cards safe. 

Is It Safe to Put Styrofoam in the Oven?

No. It is not safe to put styrofoam in the oven. Styrofoam is made from expandable polystyrene, which does not accommodate extreme temperatures. As such, you should never use styrofoam cookware in the oven. Usually, it will start to soften at 212 degrees Fahrenheit and melt at 464 degrees Fahrenheit.

You can use styrofoam containers to store leftovers in the fridge but never use them to reheat food in the oven. 

While styrofoam is microwave safe, do not use it in the oven. It has a melting temperature of up to 400 degrees Fanhereit and can quickly attain these temperatures when put in the oven. Additionally, styrofoam is highly flammable and can quickly explode when used in the oven.  

Oven temperatures vary from that of a microwave. So when you put styrofoam in the oven, it will start to melt and eventually go up in flames. This can be a threat to your health in the following ways. 

When styrofoam burns, it produces toxic smoke, which can be harmful when inhaled. Again, styrofoam can be hazardous to your entire household upon catching fire. And because putting out the fire in an oven is nearly impossible, it helps to take precautions.  

What Is Styrofoam?

Styrofoam refers to a type of expanded polystyrene manufactured through the extrusion of polystyrene foam. Before going deep into what polystyrene is and the process involved in making styrofoam, let’s take a look at the differences between expanded polystyrene and extruded polystyrene: 

• The manufacturing process of extruded polystyrene involves mixing ingredients and melting them together. 
• With expanded polystyrene, heat or steam is smeared to the molds filled with polystyrene beads. This forces them to develop and cling together. 

Polystyrene is a robust plastic material used in the manufacturing of various products used regularly. It’s obtained from the monomer styrene. When converted into a foam, polystyrene is most preferred for its cushioning properties.  

If you carefully observe a piece of styrofoam, you’ll notice several white spheres. Often, these are substances that have been expanded from a specific object, regardless of the material. Polystyrene beads are relatively smaller than the expanded spheres in styrofoam. 

In practice, put the polystyrene beads in an air-tight metallic mold. Do not pack the molds with beads; instead, fill them with a ⅓ of it. Bring them to a boil for a few minutes and let cool. Upon opening it, you’ll notice a significant expansion in the beads.  

What Is Styrofoam Used For? 

Styrofoam applies to most kitchenware – from food containers all through cups and plates. This type of packaging is lightweight and suitable for preserving cold food. That is why most food deliveries are done in a styrofoam container. It is quite popular today. 

What Is the Purpose of Styrofoam Packaging for Food?

If styrofoam containers aren’t oven-safe, then what’s the reason for packing food in them? Well, there are many reasons why restaurants prefer styrofoam for storing food. 

First, the material (Polystyrene) is relatively cheaper than the other packaging alternatives. While alternatives such as bioplastics, recycled aluminum, and biodegradable papers are eco-friendly, they aren’t cost-effective. 

Secondly, styrofoam is beneficial to insulation. The foam includes thermal insulation, which is excellent for maintaining the temperature of your food. With styrofoam, you don’t have to worry about heat regulations during transportation. 

Lastly, styrofoam is lightweight for easy mobility and portability. The configuration also makes it easy to carry the containers around, thus an ideal option for digital nomads.  

What Temperatures Can Styrofoam Withstand?

Polystyrene starts to soften at 212 degrees Fahrenheit and melt at 464 degrees Fahrenheit. And because styrofoam is made of expanded polystyrene, it will melt upon placing it in the oven.

For this reason, never put styrofoam containers in the oven. Polystyrene cannot accommodate extreme temperatures, so you can use it to preserve food in the fridge instead. 

What’s the Melting Point? 

As mentioned before, styrofoam is expanded polystyrene and begins to melt at 464 degrees Fahrenheit (240 degrees Celsius). It’s worth noting that this is the melting point, and as such, styrofoam will start softening before it attains this degree.

212 degrees Fahrenheit (100 degrees Celsius) is the lowest heat it can accommodate, but it will still soften. Therefore, it’s advisable to be extra cautious whenever you have a styrofoam item near heat.    

What Happens When You Put Styrofoam in the Oven?

If you put styrofoam in the oven, it begins to decompose. Leaving styrofoam unattended in the oven will cause it to melt into a soft, sticky heap. Since styrofoam incorporates styrene, some oil may be produced when it burns. Styrene is an organic component and oily liquid.   

Note that this will only happen if the oven is scorching. While polystyrene is excellent for preserving food in the refrigerator, avoid using it in the oven. This is because polystyrene is a plastic form that can melt in a hot oven, releasing toxic substances into your food. 

What to Use for Baking in the Oven Instead of Styrofoam?

Now that you know styrofoam isn’t safe to use in the oven, what are some of its alternatives to operating it in the oven? Let’s find out: 

1. Oven-Safe Container

Although styrofoam isn’t safe to use in the oven, there are many alternatives for oven-safe containers. For complete effectiveness, check out the oven-safe label in your boxes before putting them in the oven. 

2. On a Cookie Sheet

Depending on the kind of food you’re about to reheat, any flat cookware like a cookie sheet would get the job done. They are spacious enough to facilitate even cooking while in the oven. Unlike containers, cookie sheets are relatively fast when it comes to conducting heat. 

3. On Aluminum Foil

Aluminum foil enhances the cleanup process of your cookwares after using them in the oven. For efficiency, line it on your pans, especially when heating messy foods. Once you’re done with the cooking, simply remove the foil and dispose of it off.  

What Happens When You Microwave Food in Styrofoam?

Like in the oven, styrofoam will soften in the microwave and eventually release toxic components to your food. While styrofoam is acceptable to use in the microwave, it’s not recommended as it involves the heating process. 

However, it’s worth noting that microwave-safe styrofoam is built to accommodate the waves in the oven, and it’s perfectly safe to consume food from it. You just have to ensure that it’s the right material to avoid complicating things. 

What Should You Use Styrofoam Containers For?

Styrofoam containers can be beneficial in many ways, including storing cold food. So it’s perfectly okay to put your leftovers in a styrofoam container and store them in the refrigerator for future use. 

Similarly, you can utilize styrofoam cups for cold beverages. Refrain from putting hot drinks in these cups. Even though styrofoam cups are said to maintain the temperature of hot drinks for longer, they are not recommended for use with any hot beverage. 

Instead, use paper cups for hot drinks. They are relatively safe, plus they are easy to recycle compared to other materials. Also, avoid using styrofoam containers for highly acidic foods. Such include dishes with tomato sauce. 

This also implies that you should never use acidic drinks such as cocktails and citrus juices in styrofoam cups. You can use glass cups instead, as they can withstand the acidity. Meanwhile, do not use styrofoam cups for alcoholic drinks, as well as containers for oily foods. In other words, only use styrofoam cups and containers for items that are not acidic, oily, or alcohol-based. 

Microwave Safe vs. Oven Safe Styrofoam

If Styrofoam isn’t oven-safe, why is it considered microwave-safe? Well, microwaves incorporate a magnetron cooking method that causes molecules in your food to vibrate, generating heat. The chemical composition of styrofoam contributes to this heating process, thus microwave-safe. 

In contrast, ovens incorporate general heating by applying extreme, radiant heat to items through an electric heater. Similarly, this will apply heat to the styrofoam, causing it to burn and eventually melt. This will mean safety and health hazards, as previously stated. 

Even so, you need to check for the microwave-safe label before tossing it into the microwave. Today, most styrofoam is, but it would help if you double-check to be on the safer side. This difference in the heating mode is what makes styrofoam microwave-safe and not oven-safe.

As much as you want this kitchen appliance to come to your rescue, safety should be your number one priority. By not putting styrofoam in the oven, you’ll not only enhance your safety but the safety of your entire household, including your pets. Burnt styrofoam can be a fire hazard or, even worse, cause health problems by inhaling the toxic smoke. 

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