My understanding (I'm not a rabbi, but I'm good with google) is that expressed breastmilk is 100% kosher and even considered parve (non-meat/non-dairy) so you can have it with meat or dairy products. Of course it's a moot issue since at least in the USA you won't ever be required to taste it.

This is true! Breastmilk is parve and exempt from the separation rules (says someone whose family has not been kosher in three generations). Bing! One point to the micah for knowing remote kosher factoids!!

I once had a coworker run up to me on a flight, saying that a "Jewish guy" wanted a peach and how could he tell if a peach was kosher or not. I thought it was a joke...

Luckily, from dairy to meat there is no waiting period (there is for the opposite) so it would not pose any ethical problems if religious parents had to taste their child's formula.

This is a good article on kashrut, if anyone is interested, or even just curious;
http://www.jewfaq.org/kashrut.htm

I'm familiar with the TSA rules so I should have clarified. I'm assuming those of you who had to take international flights might have run into this. Also, perhaps before the TSA came out and said they wouldn't do the tasting. Were you given the option of giving it to the child to taste? If the child had a bottle in his or her mouth as they were going through security, that would exempt the parent from having to do this or not? Where are these tastings occurring these days? The U.K.? Middle East? I know France and Germany are okay.

I like that licking it off the hand as to not contaminate the bottle. Good thinking! I imagine it's not good though, sort of a sugary cardboard taste?

I was just wondering since my two post 9/11 babies never had formula (my oldest did since I returned to work after his birth but 9/11 during my next pregnancy nixed that plan...) As older kids, they were asked to drink from sippy cups though a couple of times.