Heating up formula in the microwave.....

[Lucy10]

I know this is considered a no no but I know a lot of people do it, so was just wondering how long you should put the bottle in for....?

All depends how much milk and how powerful your microwave - try in 10 sec bursts and shake and test with your finger after each one. You'll soon get an idea of how much it needs. I think ours takes 30 secs to heat 4oz, but tbh I give it at room temperature as it's much easier!

Thanks for the tip! I usually give a lot at room temperature but am now using pre prepared bottles and keeping them in the fridge.

Almost forgot, lid on or off?!

I zap the water and then add the formula powder, water seems to heat up faster, you should leave the lid off or at least unscrewed.

We do 40 seconds cos DD loves hot milk (sort of like drinkable tea temp.)

Lucy, are you aware of the new guidelines for making up formula?

Just wondering whether you knew it wasn't advised to prepare feeds in advance, even if you're going to refrigerate them till you use them.

Not getting at you, honest

I give my ds's bottles 50 seconds in the microwave if they have been in the fridge so that they are warm but if they have just been made up from the carton 30 seconds is fine. He has 7oz and the microwave is 1000w. I always give the bottle a really good shake though just in case there are any hot spots - been doing this for about 9 months now (ds is one in a couple of weeks) and we have never had a problem.

Hi hunkermunker, I am aware that it isn't necessarily advised to prepare feeds inb advance but I talked it through with my GP who said that as long as they are used within 24 hours then they will be fine.

I used to do lid on (don't like the idea of anything in the microwave getting near the teat). Gave a good shake between each heat burst of you heat up in stages then when hot enough I unscrewed the top of the bottle and put it back on, got a better milk flow that way - sometimes the heating can cause a pressure build up and the milk would come out to quickly.

Yes you aren't supposed to make up formula in advance now (just in case you missed hunkers post there and weren't aware of the new guidelines)

It's very difficult to keep up with the constantly changing guidelines Can anyone tell me what the difference is between preparing formula in advance, storing it in the fridge and using it within 24 hours and the readymade stuff which can be opened and left in the fridge for 24 hours?

The difference is about 35p a bottle

Very true!

Very true!

Bugs can grown in teh milk stored in teh fridge basically.

I stored made up milk milk with DTDs 5 yrs ago

I stored boiled water in bottles and added powder as req for DD3 18m ago.

I can honestly say that it is (perhaps surprisingly) much easier to do the later.

prep water. Leave at room temp.

Plonk bottle in micy when baby needs it. Plokn in powder and mix well. Serve.

Oh and you should remove teaat and lid before putting in the micy

Powdered formula isn't sterile at any point - that's the difference between that and the ready-to-use stuff, which, afaik, is heat-treated to sterilise it.

We use ready made stuff, at room temp, but keep in the fridge. It's about 30secs in our microwave to warm fridge-cool stuff to room temp in the bottle, without teat or lid, just open.

I can understand the powdered formula not being sterile but not sure how the ready made stuff can stay sterile in the fridge when left in an open carton. Yet the powdered stuff doesn't stay sterile if it's left in an unopened sterilised bottle.

we used to put 8oz cold water in the bottle put it in the microwave for 30-40 seconds then add 8 scoops formula.

Lucy, the powdered formula is never sterile. It fairly regularly contains bugs such as Enterobacter sakazakii and salmonella (one study found Enterobacter sakazakii in 14% of samples tested).

This is why the guidelines say to make it up with water which is 70 degrees or more, and not to make it up then keep it in the fridge until you want it.

Ready to use infant formula is sterile before opening.

Hunker, I understand that the ready made infant formula is sterile before opening, but don't understand how it can stay sterile in an opened carton in the fridge.

HM I think what she's trying to say is that if you use water of the correct temp (ie hot enough to kill the bugs which is regularly contains) in a sterilised bottle how does the milk then become unsterile when stored unopoedn in the fridge.

Whereas readymade formula is sterile before it's opened, but presumably becomes unsterile once left open in the fridge.......

It doesn't stay sterile.

But afaik, it doesn't have Enterobacter sakazakii or salmonella leaping into it as soon as you open it.

but if powered formula contains the bugs that it does, and you have to use water of 70 degrees (presumably to kill the bugs??) how do the bugs suddenly "reappear" if it's then put into the fridge?

Surely if they can still be there, there's no point in specifying the water has to be a ceertain temp first???

Thanks FAQ that's exactly my point

HM, I know it can't stay sterile so I'm wondering why it's okay to give that to a baby and not pre-prepared formula which has been stored in an unopened sterile bottle

See this confuses me too - i am aware of the new guidelines that have changed since i had my last child, but still want to make bottles up in advance.

May try Shreks way - is that considered ok?