People in the UK actively go out to have a meal, either to relax their minds or to avoid cooking at home. Approximately 31 million to 33 million adults go out to eat at least once a week in the UK, which is sure a great number, and every 1 in 5 people take home their leftover meals. Around 68% of the food places in the UK rely on cardboard or corrugated boxes to give leftovers to their diners.

People would come home and keep the leftover food in the refrigerator in the same box. They take out the food to microwave it in the same cardboard box before consuming it. This raises an important question: whether it is safe to put a cardboard box into the microwave? If you are looking for a straight yes or no, you may want to read the detailed reasoning behind both yes and no. There are certain conditions in which you can safely microwave food in a cardboard box, but there are some conditions that may cause a hazard. Let’s dive deeper to understand cardboard food boxes and when you can microwave them.

Manufacturing Of Cardboard Food Boxes

Food boxes are manufactured differently from other normal cardboard boxes. They are made in accordance with strict food safety standards to create a barrier against heat and grease present in food items. Below is the manufacturing process of a basic cardboard food box:

• Pulping: Recycled paper and virgin wood pulp are blended to create a layer of slightly thick paper. This creates a basic structure for the food box, which is then transformed into the desired shapes.
• Food-Grade Coating: A special coating is used to prevent the box from turning soggy and greasy. A basic polyethene coating is commonly used, and some use different water-based or plant-based coatings.
• Printing: Specified printing technologies are used for branding and marketing purposes.

• Cutting: After the printing and branding, machines are used to cut the cardboard into the desired size.
• Folding: Boxes are folded and glued using food-safe adhesives.

Components Of Cardboard Food Boxes 

Cardboard food boxes are manufactured to protect your food during transportation, from the restaurant to your home. When you use them for reheating, they may be exposed to radiation and frequencies that can harm your food and can cause a fire hazard as well. Let’s have a look at the basic anatomy of a cardboard food box:

Figuring Out Whether A Takeaway Cardboard Box Is Safe To Put In A Microwave or Not? 

Cardboard boxes usually have text on the bottom saying whether the box is safe to put in a microwave. You either see text saying microwave-safe or you can see three horizontal wavy lines. If you see any of those, you can microwave the box. If there are neither lines nor text, it might not be safe to reheat your food in it. There are some signs you may look for to get an idea about the safety of your cardboard box. Read the signs below.

When Can You Use Cardboard For Reheating Food?

If you find any of these signs on your cardboard boxes, it is okay to microwave. But keep in mind, heating even food-safe cardboard for more than 60-90 seconds can cause a fire hazard, as the heat can dry out the moisture in the cardboard and cause it to catch fire. Below are the signs you will find on microwave-safe cardboard:

• Three wavy horizontal lines indicate that the box is safe to reheat food in the microwave.
• Some boxes will have text written at the bottom saying microwave-safe or microwavable.
• A recycling triangle with 5 written inside it, or PP written under the triangle, also indicates the safety to use in the microwave.
• Pure cardboard made of cellulose without any coatings, laminations and binding materials is safe to use in the microwave in intervals of 30 seconds.

When To Avoid Putting Cardboard In The Microwave

There are various signs that are clear red flags, and if you see them, you are not supposed to microwave your cardboard box. The following are the signs:

• If you notice a binding substance or adhesives like tape or glue, do not microwave it.
• Restaurants use certain laminations and coatings to enhance the visuals of the takeaway boxes. Heating up such coatings and laminations may release microplastics directly into your food, causing health issues.
• Some bakeries often staple the boxes so it stays in place; look for the staple pins and remove them before you heat them.
• Printed boxes contain chemicals that are likely to catch fire, so avoid reheating your pizzas in printed cardboard boxes.
• A recycle symbol with the number 1 or 6 written inside gives a clear indication of chemical release after heating that most diners miss.
• Never heat for more than 30 seconds in one go. Always stir the food at least every 30 seconds.
• Always remove the lid of the box before heating it. The lids usually contain adhesives or sticky substances, so they may catch fire.

How To Reheat Your Food In The Microwave

Reheating food is a crucial step when the food is in a cardboard box.

• It is always recommended to use a ceramic or glass plate to transfer your food onto before heating in the microwave.
• Do not put cardboard in any oven or toaster or anywhere near direct heat.
• Spread out the food evenly on the plate so it gets nicely warm.
• Microwave use radiates and dries out the moisture present in food, so it is recommended to add a splash of water before putting your food inside the microwave.
• Never keep any food in any plate or box inside the microwave for more than 30-40 seconds at once. Always microwave in intervals and stir in between.

Final Thoughts

At the Custom Boxes Market, you can get cardboard boxes for your food items at affordable rates. You can get amazing discounts on your bulk orders. We have a variety of food boxes available, and you can get free design assistance from our expert team of designers.

Request a quote now and get free shipping all across the UK. Place your orders now at CustomBoxesMarket!