Making up powder formula using cooled boiled water and boiling water- remind me!

[MrsHY1]

Hello
I know it might be a bit askance from the 'approved' method but did I read somewhere that bottles can be made up by pouring boiling water into the sterile bottles (half quantity of the total water required for the feed), refrigerating, then when a feed is required add the formula to the bottle, top up with the remaining quantity of water required from the boiling kettle, shake and serve? My DD is now having a few formula feeds each day and I'm using cartons, but would like to keep these for when I'm out and about/ for when I drop night breast feeds/ when she does! Thanks guys

[jaggythistle]

No you would need too add hot water first to kill any bacteria in the powder, then add a measured quantity of cold.

Powdered formula is not sterile so that's what the 70C thing is about.

[Mumof3xx]

The way some do it is keep cool boiled in the fridge

Add half amount of water needed fresh boiled to bottle
Add formula
Add cooled

Personally I make mine from scratch

[sugarandspite]

I think you need to make sure you are aware of the underlying theory behind formula making up. So:

• Powdered formula almost certainly contains a range of microbes and bacterias.
  
• Adding powder to cold / cool water doesn't kill the bacteria so they are (more) likely to multiply and possibly cause illness.
  
• Adding powder to boiling water will kill the bacteria BUT the v hot water will also damage some of the proteins and enzymes in the milk, making it less nutritionally balanced.
  

• Hence the instruction for mixing powder and 70degree water as it gets the best balance between killing bacteria but not damaging the milk.
  

So your best approach would be to add boiling water to cooled boiled water with the ratio such that you end up with a 70 degree mix (you'll need to practice ratios a few times with a thermometer to be sure). Then add powder to your 70 degree water mix.

Then either feed bottle once cool enough to drink. Or cool bottle rapidly under a cold tap and put in fridge. Use within (I think) 12 hours.

[MrsHY1]

Thanks everyone, that's really helpful. Sugarandspite, I appreciate the explanation as it makes much more sense to me now!