Bottled water and Security Gate Check Question?

I recently contact the TSA and they told me that they just implented a new rule that you can bring water through the gate if you declare it for mixing infant formula (before you had to buy water after the gate check). I forgot to ask them wheather the water had to be in it's original sealed bottle or can it be premeasured and put into the baby bottles. Anyone know the answer to this? I already bought small water bottles made by Nursery Water. I can bring them as is but it would be even better if I can put them into her baby bottles so they would be ready for dumping the powder in!