Good point!
Then skip that point (I was still thinking shampoo, etc.) but do the wrapping and make sure it's surrounded by soft things.
I flew last summer from Israel to Paris with olive oil in two glass bottles and they arrived in good shape. My friend in Israel sends relatives to S. Africa with these bottles (family buisness) and so far, not one has busted (nor frozen). So hope you have similar luck with the formula.
I actually never noticed a difference in sleep patterns between RTF and powdered formula. I was just so happy I found a formula that didn't give my son any allergic reactions, I didn't care how it came!
Now you can take bottled water through security so that's no longer a concern.
Can you imagine if the bags in the hold froze? How many upset passengers with ruined liquids that would mean? Especially now since no one can take them in the cabin.