Anonymous wrote:It's illegal, because it's full of bacteria, OP, but if you disguise it as toiletry and put a small sealed bottle with your other shampoos, etc, no one will be the wiser. I'd put it in the hold, because the baggage compartment is usually kept above freezing, but is notably colder than the cabin.
Actually, it is totally legal only if you have the bacteria in it- Lactobacillus bulgaricus and Streptococcus thermophilus. You are allowed yogurt as long as it is less than 3.4 ounces and fits in clear quart bag.
OP you should take two in case one dies.