Originally Posted by Kathy13118
If you weigh a raw potato and then bake it in the microwave and it ends up being heavier, I have no idea how that could happen. I imagine your scale must be accurate and you zero in before weighing each time so it's a mystery where those 10 calories came from!
Actually, a baked (in oven) potato is lighter than the raw...by 48 grams. I assume that this is loss of water through steam. But again, why the calorie difference, unless it develops some type of different starch when cooked...who knows. I'm not obsessing about an accurate count; I weigh in grams, always, same scale, always zero out. My perception is that there really is no way, aside from having a lab in your basement, to get a 100% accurate calorie count; we just have to do the best we can. Also, some of FD's values aren't consistent with other sources, so there's another source of error right there.
Also, IIRC, the 20% error does not have to do with the weight (more food or less food per package), it has to do with the calorie / nutrition counts of the serving size. Take a look at this article: http://www.nytimes.com/2010/01/12/he...calo.html?_r=0
. So no matter how accurately we weigh and calculate, we might still be off a good bit!