Can You Put Plastic Bags in Microwave? What Happens?

Last Updated on November 28, 2022 by Claire

Can you put plastic bags in microwave? Putting plastics in microwave tends to release harmful chemicals like BPA and phthalates into your foods and drinks. Thus, avoid microwaving plastic unless it’s labeled for it.

Perhaps, you’re skeptical about putting their food in a plastic storage bag for cooking in a microwave oven. Somehow, it’s safe to use or put plastic storage bags in the microwave, so far you leave at least an inch at the top of the bag for the steam to escape (venting). You don’t overheat the plastic bag past a certain temperature of about 110° C (230° F) causing it to melt.

However, you must note that you should not use plastic bags to microwave foods that need to cook for a very long time at very high temperatures of over 75° C (165° F) as they can melt resulting in food contamination and or poisoning. This is due to the fact that microwave cooking times vary significantly depending on the type and quantity of food being cooked, the power level in use, the type of container in use, and the wattage of the microwave in use.

Healthline has pointed out also that microwaving plastic can release harmful chemicals like BPA and phthalates.

Can you put plastic bags in microwave

Can you put plastic bags in microwave?

You can microwave plastic bags. However, plastics intended for food use—whether designed for microwave use or not—must meet the U.S. Food and Drug Administration (FDA) standards before they are certified for use by the public. This is an important consideration for most manufacturers when they are developing plastic packaging products intended for commercial use.

The decision to microwave your food with a plastic storage bag not labeled for microwave use isn’t actually ‘unsafe’, the only issue is that you might not be assured of its safety because you know the plastic bag wasn’t approved for that type of use by the FDA.

Here’s a list of the types of plastic bags you can use in a microwave and some frequently asked questions about them:

  • Ziploc bags
  • Microwave popcorn bags
  • Freezer bags
  • Stasher bags
  • Great value Ziploc bags
  • ISTAD bags
  • Foodsaver bags
  • Ziploc Plastic bags

‘Ziploc’ is simply a brand name for bags that can be closed securely with the use of a plastic zipper. Some of these bags are also manufactured with slider enclosures making them easier to open and close and are as secure as their zipper-enabled siblings.

Ziploc bags are safe to use in defrosting and heating any type of foods  such as frozen vegetables, sauces, fish, grains, and more in a microwave, but you must make sure there is a one-inch space in the zipper closure for venting purposes and use a ‘medium’ to carefully pick up the bag after heating to avoid burns or spills as the bag can get really hot after microwave use.

Ziploc Plastic Bags are free of dangerous chemicals like dioxins and BPA that are associated with the growth of cancer. Ziploc also manufactures steam-vented bags which are specially designed for microwave use.

Is it safe to use microwave popcorn bags in microwaves?

Microwave popcorn bags are considered safe for use only if they have been tested to contain nearly undetectable per-fluorinated compounds or none at all and are approved for public use to eliminate or severely reduce any health hazards associated with these chemicals.

It’s worth noting that commercial-grade microwave popcorn bags don’t have the high-temperature melting issues that plastic bags do, primarily because they are made of paper.

However, microwave popcorn bags may contain per-fluorinated chemical compounds (referred to as PFCs, PFAs, or PFOAs), the same chemicals used in Teflon non-stick finishes which have been linked to certain kinds of cancer via tests conducted on animals. Although its link to human cancer is inconclusive, the American Cancer Society (ACS) still classifies per-fluorinated chemical compounds (PFCs) as a “potential” health hazard.

Is it safe to put freezer bags in the microwave?

It is safe to microwave any type of freezer bag, as long as you follow precautions about venting and avoid extremely high food temperatures for a long time.

Freezer bags are made of the same polyethylene material as regular storage bags with the only difference being that freezer bags are thicker and more durable than regular plastic storage bags making them better for microwaving frozen food.

You must also remember that the same precautions for microwaving food in a regular storage plastic bag also apply to freezer bags.

Are stasher bags microwave safe?

Stasher bags are microwave-safe, reusable storage bags made of platinum silicone that can last several years of use when properly cared for.

You can freeze prepared foods in Stasher bags and then defrost and reheat them when ready, you just need to make sure you open the bag a little to vent them.

Can you put Great Value Ziploc bags in microwave?

Yes, you can put Great Value Ziploc Bags in the microwave. Provided you use it to cook foods for a maximum of two minutes at temperatures below 120° F (48-50° C) and only use it to defrost or reheat previously prepared food not raw foods in order to prevent damage to the bag.

Great Value bags are a brand of polyethylene plastic storage bags sold by Walmart.

They have similar characteristics to Ziploc bags. You must make sure there is a one-inch space in the zipper closure for venting purposes and use a ‘medium’ to carefully pick up the bag after heating to avoid burns or injuries due to spills as the bag can get really hot after microwave use.

Can you put ISTAD bags in microwave?

ISTAD Plastic Bags are reusable double seal zipper-lock bags weighing about 458 grams designed by IKEA and capable of withstanding temperatures of up to 122° F (50° C) during microwave use.

So, yes, you can put ISTAD plastic bags in the microwave. However, you must be aware that these bags have a temperature range of 50° C which is lower than the cooking temperature of some foods, making them more suited to microwaving foods with short cooking times and low power requirements.

Are Foodsaver bags microwave safe?

‘Foodsaver’ is a brand name for a kitchenware range of plastic vacuum sealer bags available in several sizes.

It is safe to microwave certain types of foods in Foodsaver bags; provided you do not cook raw foods or foods with a lot of oily content and you vent the bag by cutting off a corner to let the steam out while cooking as recommended by the Foodsaver Company.

These bags are made of polyethylene with an external layer of nylon on the outside that strengthens the bag, making them suitable for heating food that’s already been cooked or simmering food just below its boiling point.

The Foodsaver Company also manufactures quart-sized vacuum-sealed bags which are especially recommended for microwave cooking.

How long can I microwave a plastic bag?

The fact is that it’s the food inside the bag, not the bag itself that actually determines how long you can microwave a plastic bag. If the food inside the bag exceeds the maximum temperature the plastic can withstand, then the bag might begin to soften or melt resulting in health hazards due to the risk of food contamination.

Theoretically, it is possible to boil water in the microwave since water has a boiling point of 100° C (212° F). This means that when you microwave foods that have high liquid content such as soup, sauce, or gravy, and it begins to boil, it could cause the bag to soften and melt or stretch losing its rigidity and resulting in possible leakage and burns. So it’s advisable to always pour foods with a high liquid content into a microwave-safe bowl.

To avoid breakage when microwaving using a plastic storage bag (especially Ziploc bags), follow this process to check how strong the bag is:

It’s advisable to set a timer for less time than the recommended cooking time when microwaving using a plastic storage bag,

After the timer is up, check the progress of your cooking and add more small time increments to finish the process,

Also, remember you have the option of pausing the microwave timer to check the food (and bag) at any time for spills or leaks during the cooking process.

The bottom line

We wrap it up with the question “can you put plastic bags in microwave?” All of the Ziploc, Microwave Popcorn, Freezer, Stasher, Great Value, ISTAD, and Foodsaver Bags are suitable for microwave use.

However, you must be extra careful by making sure you observe each plastic bag’s maximum temperature range, limits, and the type of food each is more suited to in other to avoid damages or burns due to spills (in the case of liquid foods).