For the nursing mommies out there, I found this in one of my million magazines I get. I found it interesting!
Here's how long (on average) it takes for various flavors and substances to travel from your tummy to your milk:
Caffeine -> 15 to 60 minutes
Alcohol -> 30 to 90 minutes
Cow's milk allergens -> 1 to 2 hours
Garlic -> 2 hours
Carrots -> 2 to 3 hours
Mint flavor -> 4 to 6 hours
Bananas -> Never! The taste doesn't come through the milk