I wouldn’t think so. A physical change over time would do it, but not a one time event.

Not the quality, but dairy farmers will say stress will affect milk production in regards to quantity. Humans can be affected. It is a well known fact that many breast feeding mom’s will leak if they hear a baby crying. I assume that it is a result of increased production.
Studies have been done to learn what types of music will bring on better milk production.

I am reminded of Carnation’s slogan, “milk from contented cows.” Here is an article that says the environment of dairy cows is far from one of contentment. The quality of the milk produced must still be pretty good.

Interesting question.

I know cortisol from the mother can transfer into the breast milk. Not sure if it affects the taste.

However, I know that adrenaline can affect your taste buds.

Can’t look up any research because NIH servers seem to be down. :/

They couldn’t sing it if it wasn’t true…

I don’t think so. In their natural habitat that once was, a scare could come along on a very regular basis and the babies these animals produced showed no signs of any change in mother’s milk. Beside, there is too much milk in the udder to be affected by some momentary scare.

Quantity but not quality.

Well.. I’ve heard of people having the piss scared out of them, but milk? Anybody’s guess. I’m lactose intolorent anyway.