My toddler drinks about a quart of bone broth throughout the day. I usually warm it up in a stainless steel saucepan and give it to him in his sippy cup. We're visiting family out of state right now and while I brought plenty of broth, I didn't bring my pan. So which is least bad- warming it up in a Teflon saucepan on the stove or using the microwave (with the broth in a glass jar)?
Microwaves are not ionizing radiation. They do not make changes in food that are any different than any other form of cooking. Microwave ovens simply cook food in a different manner, much like electric stoves heat food differently than gas flame or wood or coals.
Teflon or any other non-stick pans impart chemicals into your food and air, whether or not they are scratched.
The chemicals they impart into your food and environment are know carcinogens. Start here: http://environmentalhealthnews.org/archives.jsp?tn=1title,lede,description,text,subject,publishername,coverage,reporter&tv=pfoa&ss=1
I have a degree in science, so I don't make these statements lightly, and I've researched them thoroughly.
All cooking will destroy one kind of nutrient or another, while also making others more readily available.
Learning how to cook without non-stick pans, much like cooking on a grill, is about becoming in tune with time and temps and helpers (like the right kind of oil for the temp - butter browns too fast at high temps, so bad for searing, while coconut and olive oils can take higher heat) and a bit of patience... learning to know when meat or eggs are ready to be released from the pan easily or not... it's a kind of zen that can be a marvelous part of life if one chooses to embrace it and ditch the chemical-laden crutches.
That said, the microwave is a great time saver for reheating (especially if it has low power settings) and a very safe crutch to use, as long as you're not reheating in plastic. I use ceramic or glass bowls with a plate to cover, or vice versa to reheat things, or to steam veggies. I never use it to cook meat (I don't enjoy eating leather). The microwave is also great for boiling water for tea or whatever.
Most if not all forms of cooking — this includes microwaving — cause some degree of nutrient loss.
Results of two studies reached conclusions that do not damn microwaving per se. I would guess that other studies have reached the same conclusions. And that just as many studies can be found that are highly critical of microwaving. Different studies, methods, sample sizes, experimenter prejudices, and so forth. Always helpful to know who's funding a given body of science research.
Highlights of the two studies not unsympathetic to microwaving vis-a-vis food value:
"A study published in the Journal of Zhejiang University in 2009 compared the impact steaming, microwaving, boiling, stir-frying, and stir-frying followed by boiling (stir-frying/boiling) had on the nutrients of broccoli. Steaming was the method for preserving nutrients. Microwaved broccoli had a similar carotenoid content, slightly less vitamin C and only about half the glucosinolate compounds, known for their cancer-protective properties, compared with raw broccoli. However, broccoli was microwaved for five minutes.... A study from Cornell University also found that microwaved bacon contains fewer nitrosamines, a cancer-causing compound, compared with traditionally cooked bacon."
Microwaving and Antioxidant Capacity of Vegetables
"Researchers published a study in 2009 in the Journal of Food Science to investigate the impact of different cooking methods, such as boiling, microwaving, pressure-cooking, griddling, frying and baking, on the antioxidant capacity of 20 different vegetables. Vegetables cooked in the microwave oven generally had a higher antioxidant content, as if griddling and baking, compared with those cooked in water."
Another option is to use a 'double-boiler- method. Put your glass container in a water bath, and heat the water, and let the hot water heat the liquid in the glass container. It doesn't need to be hot-hot... just warmed enough to be palatable Under no circumstances would I give my kids food or beverages heated in a microwave. (When I travel, I even take my Turbo-Oven with me so I can heat things up in the hotel--'course, some would call me 'obsessive' LOL).
I agree with others here, microwave heating is nothing to be concerned about. As a research chemist, I use microwave heating for reactions quite regularly, but there's nothing magic about it, I can superheat things and get more uniform heating in a microwave than I can using other things like an oil-bath (think heating a sauce pan in a deep-fat frier).
Now Teflon… In theory, it's bad, but there's little evidence to suggest it's bad news (the same goes for BPA). Sure, it can bioaccumulate and can be found in serum and adipose, but there's little evidence that it's actually interacting with the endocrine system (as is theorized). If you burn it, it does produce toxic fumes, so don't burn teflon (duh). (For what it's worth, I work with fluorocarbons in my research as well.)
"Whatever form of gelatin is used, it should never be cooked or reheated in the microwave. According to a letter published in The Lancet, the common practice of microwaving converts l-proline to d-proline. They write, "The conversion of trans to cis forms could be hazardous because when cis-amino acids are incorporated into peptides and proteins instead of their trans isomers, this can lead to structural, functional and immunological changes." They further note that "d-proline is neurotoxic and we have reported nephrotoxic and heptatotoxic effects of this compound."55 In other words, the gelatin in homemade broth confers wonderous benefits, but if you heat it in the microwave, it becomes toxic to the liver, kidneys and nervous system."
Depends on the quality of the pan, to be honest.
Microwaves should be avoided at all costs, as well they destroy any healthy properties in food.
But if the pan is all scratched up and nasty looking, then cold broth or maybe going out and purchasing a small cheapo sauce pan for the trip may be best, but if the pan doesn't have any scratches on it, then it may be your best bet. While neither of the options are safe, never ever use the microwave.