Can You Put Cardboard In The Oven?

That piping hot pizza has just arrived, but everyone won’t be ready to eat for another thirty minutes. What is a mom to do? Most individual’s first response is to slide the boxes into the oven to make sure that the food stays warm and the crust remains crispy! While a considerate gesture, it begs to question — can you put cardboard in the oven?  

In short, just because you can do something doesn’t mean you should. While the manufacturers of the cardboard box will tell you that this material won’t set fire until the temperatures surpass 425 degrees, this statement is assuming that your oven is in perfect working condition, it has no food residue that has accumulated in it, and that the cardboard itself doesn’t have any additional printing or embellishments.

Thus, it is always best to err on the side of caution and put the pizza on a proper baking sheet to keep it warm, unless you want a potential fire on your hands. 

Cardboard & The Oven — Considerations And Safe Alternatives 

Why Not?

According to a recent survey conducted by the National Fire Protection Association, there are a whopping average of 172,900 fires that occur every single year, that are specifically triggered by kitchen-related activities.

If you dig a little deeper, you will find that 9% of those fires are caused by the misuse of material and another 9% are due to the heat source being too close to combustibles. That is over 31,000 fires that could be easily avoided! 

While we all agree that one of the main purposes of takeout is the convenience of not having to clean up after the meal, is it really worth risking irrefutable damage to your home as well as potentially threatening your family’s life to avoid washing one little cooking tray?

How Hot Is Too Hot?

Most pizza boxes are constructed with corrugated cardboard. This basically means that the box material has a ribbed interior to create better insulation for the food inside. The ignition temperature of this type of cardboard is 427 degrees.

Therefore, it is implied that if you were to set the oven to 200 degrees to keep food warm in the box, or if you were to cook a frozen pizza at a toastier 425 degrees, you would have no issue. 

However, just like in a science experiment, it is important to consider ALL of the variables. Are you stacking multiple boxes in the oven? Have you cleaned the oven recently? Is the oven new or used? Is there a company logo printed on the box? Are you leaving it in for ten minutes or an hour? Has pizza grease leaked on the cardboard? Is there a plastic liner or pizza saver inside? 

These are all factors that could play a role in the ignition of an oven fire. The claims that you can safely put cardboard in the oven do not take all the facts into consideration. Instead, they only account for what experts have determined based on experiments conducted in a controlled environment.

Of course, if you have a brand new oven and you put in a single piece of plain cardboard with no food, ink, or residue on it, it will likely take a while to catch fire. Unfortunately, you will likely not have the conditions of a test kitchen, which means that you need a different solution. 

Other Reasons To Say No To Cardboard And Cooking

Cardboard is fantastic for transport, but cooking on this material can actually cause that crispy crust to become soggy. Furthermore, it can add a particular flavor to your food that you may have not wanted as a part of your order. Using items intended for baking is important to conserving the integrity of the pizza and your safety!

Alternatives To Putting Cardboard In The Oven

When the occasion arises where you need to keep food warm or bake something that originally came on a cardboard slab, it is always best to transfer it to an item that was designed to withstand hot temperatures. 

Your options can include a metal baking tray, a silicone oven liner, a pizza stone, a pizza pan or you can just slide it directly on the rack! For those individuals who are adamant in their quest to avoid dishes, consider throwing some aluminum foil over the top of one of these kitchen tools to provide easy clean-up!

Finally, for the pizza savant, there are two other alternatives that require no cleanup AND are reusable. The first is to invest in your own pizza insulator bag.

It has worked for delivery drivers for almost the past forty years. If you intend to use it regularly, this is a surprisingly affordable solution! However, if this option is a little too extra for your taste, then just grab a blanket and wrap it around the box upon arrival. 

Put Cardboard In The Oven

Fire Safety: Putting Cardboard In The Oven

Even the most careful individuals can start a fire in the kitchen. Therefore, it is imperative that you take a few steps to prepare yourself and your home in case of an emergency. 

First, always teach your kids the importance of keeping flammable items away from any heat source. These can include cardboard, dish towels, and paper towels, to name a few. Next, have a working fire extinguisher an arms-length away! This can ensure that if a fire does start, that you can put it out quickly. Make sure to take the time to go over how to use this device.

Also, discuss with your kids the different types of fires that can occur in the kitchen. It is important to note that water is not always the best method for extinguishing certain types of flames. Grease fires actually worsen with water. Instead, you need to smother it with a cooking lid or a thick, damp towel. Baking soda and salt are other solutions as well.

Moreover, if you are cooking, the food should never be left unattended and spills should always be addressed the moment they happen. Ingredients such as flour, garlic, and bacon are all exceptionally flammable.

Additionally, the disinfectant spray that you use to clean your countertops can also be a quickfire starter. Consider cleaning with items that have less of a chance of igniting, like with good old-fashioned soap and water!

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Frequently Asked Questions

Can cardboard spontaneously combust if I put it in the oven?

Yes — cardboard is a combustible material, meaning that it can ignite quickly. This is especially true when paired with plant and meat-based fats like cooking oil or pizza grease.

This can occur even without the presence of an actual flame. All that is necessary is the right level of heat. Thus, never put cardboard in the oven, no matter how low you set the temperature. 

Can you put cardboard that is wrapped in aluminum foil in the oven?

If you put a bandaid on a bullet wound, is that going to fix the issue? Unfortunately not. Thus, as mentioned above, it is best to avoid putting cardboard in the oven. However, you can use aluminum foil on a cookie sheet or pizza stone.

Can I put the pizza boxes in the oven to keep them warm if the oven is off?

While this method will not keep the pizza in the perfect condition that it arrived in, it is the safest option you have for keeping the food warm and the fire risk non-existent. Just do not forget to pull it out, prior to turning on the oven to bake something else!

Can you cook items in a cardboard container in the microwave?

Yes, and no! If you are putting a cardboard container in the microwave for a short period of time, it should be okay under careful supervision. However, if the container has a wax or waterproof coating, ink insignias, glue, plastic or metal, you should always transfer the food into a microwave-safe container. 

Final Thoughts 

Kitchen safety is imperative. If your initiative is to keep the food warm and avoid any dishes later, invest in a pizza pan or stone. Then wrap it in aluminum foil and transfer the pizza to this oven-safe tool, prior to putting it in the oven. Lastly, set the temperature to anywhere between 140 to 200 degrees. 

Lower temperatures are ideal if you intend to leave the food in for a while. Otherwise, it will begin to dry out quickly. Experts recommend a maximum time frame of two hours, but less is best.

While it may seem tempting to skip these steps, it only takes a little distraction and the right ingredients for a spark to ignite a large fire. Remember to never leave food unattended, even if you are just warming it. Finally, and most importantly, children mimic the habits of their parents. Thus, if you utilize unsafe practices in the kitchen, they will follow suit. Keep the cardboard out of the oven!

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