Formula Feeding Your Baby:
Safely Preparing and Storing Formula
Breast milk is the healthiest choice for babies. For babies who cannot be breastfed, iron-fortified commercial infant formula is recommended. If your baby is formula fed, you must be careful to safely prepare and store the formula. If not, your baby can get sick.
What formula is available for my baby?
The different types of formula are ready-to-feed, concentrated liquid, and powdered.
Ready-to-feed formula and concentrated liquid formula are sterile until they are opened. Healthy full term babies can have ready-to-feed, concentrated liquid, or powdered formula. If powdered infant formula is used, take special care to prepare it.
If your baby is high risk, she should have ready-to-feed or concentrated liquid formula whenever this is available. If ready-to-feed or concentrated liquid formula is not available, powdered infant formula can be used, taking special care to prepare it.
Babies considered high risk include:
- premature babies under 2 months of age (premature babies are born before 37 completed weeks of pregnancy),
- low birth weight babies who weighed less than 2500 grams at birth and are under 2 months of age, and
- babies of all ages who are immunocompromised or have weakened immune systems.
How do I prepare and store ready-to-feed or concentrated liquid formula?
Follow the instructions on the formula label to prepare and store ready-to-feed or concentrated liquid formula.
Concentrated liquid formula needs to be mixed with an equal amount of previously boiled and cooled water. Do not add water to ready-to-feed formula.
How do I store powdered formula?
Store powdered formula in a cool, dry place (not in the refrigerator). The lid should be tightly closed.
Check the expiry date and make sure you use it within one month after opening. To help you remember, write the date of opening on the lid.
How do I prepare powdered formula?
Carefully follow the mixing instructions on the formula tin to find out how much water and how much powder you need to prepare the formula correctly.
Water used to prepare formula can be boiled in a covered pot on the stove or in a kettle that does not have an automatic shut-off.
- Bring water to a rolling boil, and keep boiling for 1 minute.
- The water used to mix with the powder should be at least 70° C (158° F). The hot water kills germs that might be in the formula powder.
- Use a digital thermometer to check the water temperature before you mix the formula.
- Mix the correct amount of hot water and powdered formula in a sterilized bottle. Take care to avoid scalds.
- Put a ring and nipple on the bottle and mix thoroughly by gently shaking or swirling the bottle.
If you have a healthy term baby, or a premature or low birth weight baby that is now older than 2 months, previously boiled water can be cooled to room temperature and then used to mix with the powdered formula. Formula prepared in this way must be fed to the baby right away.
How do I cool prepared powdered formula?
Formula prepared with hot water is too hot to feed to your baby. Quickly cool it by carefully placing the bottle under cold running water or in ice water. Make sure the cold water is below the ring of the bottle.
Once the bottle has been cooled, make sure it is a comfortable temperature. Test a few drops on the inside of your wrist before feeding your baby.
How do I store prepared powdered formula?
It is safest to prepare powdered infant formula one bottle at a time and to feed your baby right after you have prepared the bottle. If you do prepare bottles ahead of time, they must be prepared using water that is at least 70° C (158° F), cooled quickly under running water or in ice water, and stored in the refrigerator.
Refrigerate unused formula at 4° C (39° F) or below for up to 24 hours. Check the temperature of your refrigerator with a refrigerator thermometer. Throw away any unused prepared formula after 24 hours.
For all types of formula:
How do I warm refrigerated formula?
Formula can be given cool or at body temperature (warm). You can warm formula as follows:
- Put the bottle under warm tap water (keep the nipple area out of the water); or
- Warm in a bowl of hot water or bottle warmer for no more than 15 minutes.
Do not heat formula by:
- Putting the bottles of formula in a pot of hot water on top of the stove. The formula can get too hot too fast.
- Putting the bottles of formula in the microwave. The uneven heating of the formula can burn your baby's mouth.
Always test a few drops of heated formula on the inside of your wrist. It should feel just warm.
How long is formula safe at room temperature?
Formula is safest if it is taken out of the refrigerator, warmed up and then fed to your baby right away.
Make sure the bottle is used within 2 hours of being taken out of the refrigerator.
Always throw out any formula left in the bottle after each feed. Do not put the bottle back in the refrigerator or feed your baby leftover formula later.
Throw out any unused prepared formula that has been at room temperature for 2 or more hours.
How do I feed my baby formula away from home?
W hen feeding your baby away from home, prepared formula can be taken with you if it will be used within 2 hours. Right before you leave home, remove the cold prepared formula from the refrigerator and place it in a cooler bag with ice packs.
If you are away from home for longer than 2 hours, it is best to bring unopened ready-to-feed formula with you. If you use concentrated liquid or powdered formula, bring the supplies that you will need to prepare it safely at your destination.
For more information on formula feeding, see HealthLinkBC File #69a Formula Feeding Your Baby: Getting Started or see the Healthy Canadians guidelines on Preparing and Handling Infant Formula at healthycanadians.gc.ca/eating-nutrition/safety-salubrite/milk-lait/formula-nourrisson-eng.php.
For more information, contact your local public health unit, health care provider, or call 8-1-1 to speak to a registered nurse or registered dietitian.