Sour thai tea.......?

Question

what could possibly make a thai tea drink sour when you purchase it from a restuarant?

Answer 1

If "Iced Tea" is ordered in Thai restaurants, they will usually serve it in the Thai fashion by adding Lemon Juice and also offer cold sugar syrup on the side. It's called "Chaa Manow" which means Lemon Tea.

I encountered this when I moved to Thailand.

Answer 2

Oh my, I hope the coconut milk was fresh and not rancid!  Hope you are okay and didnt drink it.  I also hope you brought it to your waiter's attention.