789. Is heating milk by microwave advisable? - I
Microwave cooking leaves no permanent mark on the food. It causes virtually no chemical damage and absolutely no radioactivity. The only drawback with heating milk by microwave is that the heating may be uneven and may denature some protein molecules in regions of the milk that become excessively hot. Since most protein molecules are disassembled by your digestion anyway, this treatment probably has no effects worth worrying about. Even with infant formula, my only concern would be the hot spots. If you carefully shake the milk after heating, so that its temperature is uniform, it should be just fine. I suspect that companies warn you not to heat milk in a microwave because they are worried that you will either not shake the milk to distribute its temperature evenly or that you will overcook it until it boils and the bottle explodes.