Buzz
There are numerous reasons why you should avoid placing unsuitable dishes and materials in the microwave. Materials not designed for microwave use can melt, crack, or become damaged, potentially releasing harmful chemicals into your food, causing explosions or damaging the microwave. Not all microwave-safe dishes are labeled, but fortunately, you can perform a simple test to determine if an item is microwave-safe.
Steps
Check the Dish
Take a cup of water. To test if a dish is microwave-safe, place the dish and a cup of water in the microwave. Use a microwave-safe glass or ceramic cup and fill it three-quarters full with water.
- It’s crucial to use a microwave-safe cup; otherwise, the test won’t be effective.
- To be sure, look for a label on the bottom of the cup indicating it’s microwave-safe.
Heat the dish and cup of water in the microwave. Place the cup of water and the dish you want to test side by side in the microwave. Next, heat both items on the highest power setting for one minute.
- If the dish is too large to place next to the cup, simply place the cup on (or inside) the dish.
- To maximize the microwave’s power, locate the Power, Menu, or Settings button.
Check by touch. After one minute, use oven mitts or a pot holder to remove the cup of water. Then, touch the dish to feel its temperature:
- The dish is not safe for the microwave if it feels warm but the water is not hot. The warmth indicates the dish absorbed heat.
- The dish is safe for the microwave if it remains cool but the water is warm. This means the dish did not absorb heat.
- Note: The center of the dish might feel warm if you placed the cup on or inside it.
Label the dish. To keep track of which dishes are microwave-safe, use a permanent marker to note the results on the bottom of the dish.
- You can use symbols like a smiley face, the letter M, or wavy lines to mark microwave-safe dishes.
- Don’t forget to label dishes that are not microwave-safe. Use a sad face, a crossed-out M, or another indicator.
Identify Microwave-Safe Materials
Look for microwave-safe labels. The easiest way to determine if a dish or utensil is microwave-safe is to check the label on the bottom. Three indicators of microwave-safe items are:
- The phrase “microwave safe”
- The phrase “microwave friendly”
- Wavy horizontal lines
Most ceramic, glass, and porcelain items are microwave-safe. Generally, dishes made of ceramic, glass, or porcelain are safe for microwave use. However, there are exceptions to keep in mind:
- The manufacturer specifies the dish is not microwave-safe.
- The dish has metallic paint or decorations, such as gold or silver trim.
- The dish is coated with lead-based glaze.
Identify brands that offer microwave-safe products. Many companies produce heat-resistant tableware suitable for microwave use. Here are some well-known brands that specialize in such products:
- Anchor Hocking
- Duralex
- Pyrex
- Corningware
- Visions
Some paper products are microwave-safe. Certain paper items, such as parchment paper, plain white paper plates, napkins, and paper towels, are safe for microwave use.
- Avoid using paper products with printed images, logos, or text to prevent ink or dye from transferring to your food.
Learn when and how to use plastic in the microwave. Some plastic utensils and food wraps are specifically designed for microwave use and are free from plasticizers that could leach into food.
- If using plastic containers, ensure they are labeled as microwave-safe.
- When using plastic wrap, make sure it does not come into direct contact with the food.
Avoid Non-Microwave-Safe Materials
Avoid putting metal in the microwave. Unless you strictly follow safety guidelines, placing metal in the microwave is unsafe. Here are items you should never microwave:
- Plates or cups with metallic paint
- Dishes with metallic decorative trim
- Steel twist ties
- Food containers with metal rims or handles
- Aluminum foil
- Metal utensils
Identify lead-glazed dishes. Lead-based glazes were once widely used in tableware and are still common in some countries. Avoid using lead-glazed dishes for food, as lead can leach into your meals. Lead is highly toxic, and consuming contaminated food is harmful to health. Microwaving lead-glazed dishes increases the risk of lead contamination. Common items with lead glaze include:
- Ceramics with a glossy or transparent coating
- Handcrafted tableware
- Items with bright, vivid colors on the inner surface
- Antique dishes
- Shiny, intricately decorated pieces
Do not microwave cold food storage containers. Plastic containers designed solely for refrigeration often cannot withstand heat and are unsuitable for microwaving. Avoid microwaving containers used for:
- Yogurt
- Butter or margarine
- Cottage cheese
Avoid brown paper products. The USDA Food Safety and Inspection Service states that while white paper products are microwave-safe, brown paper products are not.
- This includes brown paper bags and brown paper towels.
- Similarly, newspaper is also unsafe for microwave use.
