Questions About Formula Lifespan and Preparation

Updated on January 26, 2009
V.B. asks from Thousand Oaks, CA
7 answers

Hello everybody.

The formulas that I'm familiar with (Similac, Enfamil and Kirkland) state in their directions for use to discard any leftover formula an hour after the baby started feeding. My question is, however, what happens when you prepared your formula, offered it to your baby, the baby took either just a sip or a little bit, and then doesn't want anymore? Even though the baby didn't technically have much or any of the formula, does the formula have to be discarded nonetheless or can it be put in the fridge and be given to the baby later? If the answer to that question is that I can indeed refrigerate it and use it later, will it be good for 24 hours like the refrigerated formula that hasn't been offered to the baby is or would it be good for a couple of hours only?

Another question that I have is: does the Kirkland formula really have to be prepared with boiled water or would filtered water be fine?

If the water has to be boiled, does the water have to be still warm when I give the formula to the baby or is it okay to be at room temperature?

If I can use filtered water, can it be at room temperature or would I have to warm it up a little bit either on the microwave or stove top before I prepare the formula?

It seems to be that Enfamil and Similac can both be given to the baby at room temperature, so I was surprised to read that Kirkland's formula has to be warm. Is that really true?

Thank you all in advance for your help and responses.

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So What Happened?

Thank you all for your helpful responses. It is very reassuring to hear that I don't have to boil the water and throw away the barely-touched bottle right away - it makes life so much easier! I'm very glad I asked these questions. Thank you very much for your time and kindness.

More Answers



answers from Honolulu on

I never heard that Kirkland formula has to be made with "boiled" water! Does it say that on the container?
Gee.. that is the brand I used for my son... I just used regular bottled water. It was fine. I never warmed it up first. Just room temp. We've had no problems prepping it this way...

As far as how long you can keep prepared formula IF after they take a sip... well, I've kept it around, in the fridge for a few hours, or with my son who then would drink at-will as he needed. My son never had a problem. BUT, I never kept the bottle around for 24 hours if it was already touched. I ONLY kept an already UN-touched prepared bottle in the fridge for max 24 hours.

each baby is different about how they take son took it room temp or straight from the fridge cold. Some warm it slightly. But I never did this myself.

BUT, your son is only 1 month old... so, I would STRICTLY follow the care of the formula and keep it around for only as long as stated. My son, was on formula/cows milk AFTER 1 year old.

Yes, so after your son touches/drinks from his bottle...dump it out. Bacteria can grow in it or sour the formula. ONLY keep UNTOUCHED prepared formula... and yes, it can be kept in the fridge for up to 24 hours.

Your son is young... so do follow the storing 'rules.' That is safest.

Also, so as not to 'waste'... just prepare as much as you know your son can drink. If he then needs/wants more... then prepare more, a little at a time. At this age anyway... he probably drinks 3 ounces max? At then at night, for night feedings... I used to make some bottles ahead of time, untouched bottles, kept it in the fridge.. .and when or if my son needed a feeding for whatever reason, it was already made. OR, I'd keep it in a insulated bag/ice-chest next to my bedroom. For easy access and 'efficiency' at night when I was so tired.

All the best,

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answers from San Diego on

if you're a germ-a-phobe, throw it out after the nipple has been touched by baby. but if you're like me...I'd throw it in the fridge for a few hours and not worry. The concern is whatever germs are in your kid's mouth that now have the opportunity to grow. so if your baby is healthy, I wouldn't stress over it.

Our pediatrician recommends tap water over bottled/filtered because the minerals are healthy. I always prepared formula straight from the tap and never warmed it. I used all three formulas, but primarily Kirlkland.

congrats on the little one!

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answers from Los Angeles on

I agree with the two people who have left responses so far! I say stick it in the fridge and use it soon but don't chuck it (unless you are super germophobic!). And I NEVER boiled water (my doctor told me the same thing--that tap water was fine). In fact we never heated water or milk to give to our sons either--they just got it at room temperature or tap temperature. I have a nephew that at 5 still likes his milk warmed and it was such a pain for my sister that I never wanted to go through that--my kids never minded and my 15 month (now on whole milk) had no problem with the cold milk transition (and boy was it nice in the middle of the night or when you're out and about without a place to warm the water!)

Good luck!! :)

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answers from Los Angeles on

Totally agree with Susan!

When he was still that young, I would prepare bottles for the feeding for the day, and keep them in the fridge for about 24 hours.

If he drank from it, like actually consumed it, whatever was leftover I would toss.

If he took a sip and then was over it, I would toss it in the fridge for a few hours and would offer that for the next feeding...never had any issues with that.

Also, I used bottled water for mixing, and that's what my son's Pedi said was okay to use. If the bottle was in the fridge, I would let it sit out for about twenty minutes before offering it to my son or used the bottle warmer when he got fussy about it being cold. But, otherwise room temperature is great.

Like Susan wrote, follow the instructions and if you have any questions make sure you call the information numbers on the container...enfamil is super helpful!

Good Luck and have fun!

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answers from Los Angeles on

it should be ok with whatever water you choose to use. the warm water may make it easier for the formula to mix. also in the frig the formula should be ok for like 4 hours after given to the baby. when my mom would watch my daughter she would make a big batch of formula (like 6 bottles worth) and leave it in the frig until she needed it and my daughter was fine. i gave my baby good start and used filtered room temp water then just the filtered water from the frig. she did just fine.

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answers from Los Angeles on

Hi Veronice,

I have on child and have a host of brothers and sisters that i raised. Formula is good as long as you refrigerate for 24 hours. Anytime you give a brand new baby formula it has to be on of two things. Warm or room temp. I think you already know not give a baby cold milk. Cold milk can upset your newborns stomach and give them gas. I am not very familiar with Kirland from Costco. But enfamil and similac can be held in the refrigerator for 24 hours. Usually babies drink the milk up before it can sit in the fridge for longer than 24 hours.

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answers from Los Angeles on

Hey There,
Your baby is so very young, is there a way you can breastfeed? Then none of the questions you have are at all necessary! Nature made a 24/7 bar for babies...actually two! Everything is always fresh and the exact right temperature. Portable. No mixing, no dirty bottles, no heating, no storage problems....and the milk comes in beautiful, custom designer carrying cases!!

Seriously, there are so many advantages for you and your baby...I urge you to investigate before all your milk is gone. La Leche League is a good source of good, solid info. And it's still free after all these years. These are moms supporting moms. Book knowledge is good. Experience is priceless.

Follow your heart, lovely mommy.


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