There are plenty of things you shouldn’t put in your microwave. Weetbix without milk (oh the pleasant scent of burnt bix), plastic toys (oh the stench of death one of our Barbies left last week) and we all know putting alfoil or metal in the microwave is a definite don’t.
You’ve probably also heard it’s dangerous to microwave food in plastic containers or plastic wrap because of potentially lethal food-contaminating chemicals. Or that zapping your veggies also zaps all their nutrients.
No wonder all my circa 1980’s microwave cookbooks are all dusty.
But while there are things that shouldn’t be microwaved, so much can be! As long as you’re using the right microwave safe container and out handy guide to safe microwave cooking you’ll be dusting off those cookbooks in no time at all.
Foods and Drinks
There’s a popular misconception that microwaves zap all the good stuff in our food, like essential vitamins and minerals. In fact, microwaves often retain more nutrients in our food than conventional cooking.
All cooking degrades the amount of nutrients in our food, but there are several factors to consider, including the amount of heat being applied, the amount of water used, cooking time, and the nutrients involved. Microwaves, because they tend to involve shorter cooking times and less heat, exert less destructive effects.
- Frozen pizza
- Eggs, scrambled or poached
- Kale, veggie or potato chips
- Lemons and limes, to get more juice out of them
- Vegetables, especially eggplant or frozen ones
- Desserts like any of our cake in a mug recipes
- Just about anything else except grapes. But who eats warm grapes anyhoo?
How to test if a dish is microwave safe
Fill a measuring cup with 1 cup of water then place it in the microwave with the (empty) dish you wish to test and microwave on high for one minute. If the dish feels warm after the minute, it isn’t microwave safe.
Best microwave safe containers:
- Anything made of glass. These are probably the best containers to use, as there is no debate about how safe they are.
- Most paper plates, towels, and napkins. The plastic coated types are not recommended though.
- Porcelain and stoneware, rather than ceramic dishes that may have been low fired, because those could possibly explode. Plates with metallic paint detail can also cause sparks.
- Microwave cooking bags and grease proof paper are safe products to use too.
- Plastic container marked ‘microwave safe’.
Items that should never be used in the microwave:
- Aluminium foil
- Metal containers (e.g., canned foods in their cans)
- One-time storage containers like takeaway containers, margarine or yogurt tubs.
- Plastic bags or film canisters.
- Plastic containers not marked ‘microwave safe’. Thought by many to cause cancer. Even BPA-free products leach hormone-like chemicals (although new research suggests it might not be as bad as previously thought). The jury’s still out, though, on the health implications of microwaving plastics.
Other Microwaving hints
- If you do decide to microwave in plastic containers, just make sure they’re not cracked, old, or discoloured.
- When covering food with plastic wrap, make sure the plastic doesn’t touch the food.
- Eggs intact in their shells or boiled eggs, even if the boiled egg is peeled, can explode. Cut or prick items that may be more likely to explode because of internal pressure, such as hot dogs, sausages, and potatoes. Also make sure you vent any container so steam can escape
The list of other things you shouldn’t put in the microwave is pretty long, but there are also some unusual ways to use your microwave:
- Microwave a damp sponge, to disinfect it.
- Zap Potting mix to sterilise it.
- Blitz a hand towel for a DIY hot water bottle.
- Microwave water with lemon to clean it.