Formula Preparation & Handling

Safe Preparation and Storage of Powdered Infant Formula and Handling 

The Infant Nutrition Council recommends the following best practice for Safe Preparation of Powdered Infant Formula:

More ‘Preparing Formula’ Information

  • Before use, check the ‘use-by’ date on the can.
  • Store the can in a cool, dry place.
  • Ideally prepare only one bottle of formula at a time, just before feeding.
  • Always read the instructions on the can to check the correct amount of water and powder as shown on the feeding table on the back of the can. This may vary between different formulas.
  • Add water to the bottle first, then powder
  • Take care to add the correct number of scoops to the water in the bottle. Always measure the amount of formula powder using the scoop provided in the can – scoop sizes vary between different formulas.
  • Any prepared formula left at the end of the feed must be discarded.

Other good bottle-feeding practices 

  • A feed should take no longer than one hour.
  • Any formula that has been at room temperature for longer than one hour should be discarded.
  • Keep the scoop in the can when not in use – and do not wash scoop.

Preparing feeds in advance

  1. Ideally prepare only one bottle at a time. If you do need to prepare formula in advance (for example for a babysitter) it must be refrigerated (at 4˚C or below) and used within 24 hours.
  2. Preferably refrigerate prepared sterilised bottles of boiled water and use as required, first warming by standing bottle in a container of warm water and then adding formula.
  3. If using refrigerated prepared formula, before feeding baby, warm by standing bottle in a container of warm water.
  4. Using the microwave to heat infant formula is not recommended as heating can occur unevenly and burn the baby’s mouth.

Preparing formula correctly will ensure that baby gets the right amount of nutrients

Click here to watch a short video shows you how to prepare baby formula or expressed breastmilk for bottle-feeding to newborns and young babies. The video starts with washing and sterilising bottles for baby formula or expressed breastmilk. It also takes you through the steps for making baby formula with cool, boiled water and shows you how to bottle-feed your baby.

Concerns around WHO recommendations to prepare formula at 70 degrees Celsius

Frequently Asked Questions

1. Is it possible to use formula while still breastfeeding?

Exclusive breast feeding is recommended for the first six months. However there are circumstances when exclusive breast feeding is not possible. In these circumstances, under the advice of a medical practitioner, it is possible to both breastfeed and formula feed an infant. However the introduction of partial bottle feeding could negatively affect breast feeding.

Such partial replacement of breast milk must only be with infant formula: cow’s milk (diluted or not) or other fluids are completely unsuitable and could be dangerous. The formula must be made according to instructions and no other food added to the bottle.

2. What is the correct way to use infant formula?

Always follow manufacturers’ instructions on the label to make up infant feeds. Most commonly available infant formulas are powders which must be mixed with cooled boiled water in the correct proportions. Using too much or too little powder without medical advice can make your baby very ill.

Bottles and teats must be cleaned and sterilised very carefully.

It is very important that mothers receive adequate information in order to ensure the safe use of infant formulas. Manufacturers provide this information on labels and in product literature. Additional information may be sought from your health care provider.

The Infant Nutrition Council has developed guidelines for the safe preparation and handling of infant formula.

3. What type of water should be used to make up infant formula?

Ordinary tap water from a main water supply (community drinking water – also called reticulated or town supply) is adequate for use in preparing infant formula as long as it is boiled and cooled prior to use. Use water taken fresh from the cold tap after running for 10 – 15 seconds.
If you have a bore, check with your local public health authority that your water is low in nitrate and its suitability for using to prepare infant formula. Bore water and tank water should be boiled until baby is 18 months old (NZ Ministry of Health guidelines).
Questions have been asked as to whether bottled water can be used to prepare infant formula. Food Standards Australia New Zealand has stated that plain bottled water (but not natural or sparkling mineral water or soda water) may be used to prepare infant formulas. But you should boil and cool the water you use to prepare infant formulas according to the instructions on the formula package label.
4. Why does the water need to be sterilised before making up infant formula?

For hygiene reasons, the water used to make up feeds needs to be sterile. Manufacturers recommend that water is boiled and allowed to cool before making up feeds. Bottles and teats must also be sterilised.

5.Can I prepare and store cooled boiled water in advance?

The Infant Nutrition Council recommends where possible that each infant feed be made up individually just prior to use. Always follow manufacturers’ instructions about how to make up and store infant feeds.

If cooled boiled water is prepared in advance, it must be placed in a covered, sterilised container and refrigerated below 4°C continuously and used within 24 hours.

6. Can I prepare infant formula and keep it in the fridge?

There is some variation in guidelines about the storage of made up infant formula. Australia New Zealand Food Standards states that “if a bottle of made up infant formula is to be stored prior to use, it must be refrigerated and used with 24 hours”.

The Infant Nutrition Council recommends where possible that each infant feed be made up individually just prior to use. Always follow manufacturers’ instructions about how to make up and store infant feeds. Any formula that has been made up in advance with boiled water must be refrigerated if not to be used immediately, and in any case must be used within 24 hours, or discarded.

Unfinished feeds must always be discarded and never kept for use in a later feed.

The Infant Nutrition Council has developed guidelines for the safe preparation and handling of infant formula.

7. Can I store Ready to Drink infant formula in the fridge once it is opened?

The Infant Nutrition Council recommends where possible that each infant feed be prepared individually just prior to use. Always follow manufacturers’ instructions about how to prepare and store infant feeds.
‘Ready to Drink’ infant formula products are available in aseptically packed glass bottles for hospital use only or in aseptically packed tetra packs for domestic use. However once opened, prior to use either “Ready to Drink’ formats (glass bottle or tetra pack) may be prepared into numerous sterilized bottles provided that these bottles are refrigerated below 4 °C continuously and used within 24 hours.
Any unfinished formula left in the bottle after a feed must be discarded and never kept for use in a later feed.

8. Can I keep formula that has already been made up in a vacuum flask?

No. This is definitely not recommended. Boiled water may be stored in a vacuum flask and the feed mixed when required; but never keep milk warm for any period of time as warm milk is an ideal breeding ground for bacteria.

9. Can I freeze infant formula?

Freezing made-up formula is not recommended.

10. Should you take out bottles already made up?

It’s much safer to prepare bottles of infant formula at your destination, rather than carrying around bottles of prepared formula you’ve made up at home hours earlier.

Harmful bacteria thrive in warm, moist conditions. Ready-made bottles of prepared formula can be a breeding ground for bacteria if they’ve been sitting in a car or baby bag for many hours, especially on a warm day. Bacteria can be harmful to babies as it has the potential to cause diarrhoea, vomiting and dehydration. When preparing formula always follow the instructions on the package.

11. How do you heat up infant formula?

Infant formula that has been prepared in advance and stored in the refrigerator (for no longer than 24 hours) can be heated up by standing in a pot of warm water.

Never, ever put your baby’s bottle into the microwave. Microwaves can create uneven ‘hotspots’ in the water and can potentially burn your baby’s mouth.
Before feeding, test the temperature of the formula by putting a drop on the inside of your wrist. If it’s body temperature then it’s at the right feeding temperature for your baby to drink.

12. How do you transport water and portions of formula?

There a number of special containers available that are designed to carry single serves of infant formula which are ideal if you are taking your baby out during feed times. Ensure to check the manufacturer’s instructions. We also suggest taking a separate sterilised bottle (or numerous sterilised bottles) of cooled boiled water at the correct volume, so you can make up the formula when you need it and feed immediately. But remember, wherever you are, follow the manufacturer’s instructions provided on the tin or pack of infant formula.

13. Should you always take enough supplies for extra feeds just in case?

Absolutely it’s best to be over prepared than have an unhappy and hungry baby. It’s also a good idea to take extra sterilised bottles as it eliminates the problem of washing bottles and re-using – which is not advised.

14. Can parents buy single-serve sachets or ready-to-drink formula?

Yes, you can buy single-serve sachets of infant formula powder that can be made up or packs of liquid infant formula that are available in UHT style packaging that is ready to drink without need for mixing. The liquid formula needs to be poured into a sterilised bottle and can be warmed in the bottle if desired, just before feeding. These are safe, hygienic and convenient to use. Again, it’s important to follow the manufacturer’s instructions provided on the pack.

15. What is E. Sakazakii and should I be concerned about it?

E. sakazakii is a bacterium which can cause severe illness in the infant. It is an opportunistic pathogen which is quite common in the environment. E. sakazakii infection in infants however, is not common, but when it does occur, susceptible population groups are generally very young or immunocompromised infants and the cause is generally due to unsafe preparation and storage of liquid feeds.
Infant formula manufacturers are committed to providing safe products and they do so by applying stringent hygiene measures to ensure their safety and compliance with regulatory standards in the manufacture of such products. In terms of microbiological safety, preparation and handling must adhere to strict hygiene rules and immediate consumption after preparation represents the safest option.
You should not be concerned about it, provided you follow the manufacturer’s instructions exactly on safe preparation and storage of infant formula, in order to ensure there is little risk of contamination and microbiological growth.

Further information on E. sakazakii can be found here.

16. What's the best way to avoid dental health problems when feeding?

In rare incidences, cases of dental caries have arisen from prolonged ad lib breastfeeding and inappropriate bottle feeding.

This is because both breastmilk and infant formulas contain sugars, either in the form of lactose, or in the case of soy infant formulas, glucose syrups. Any sugar-containing fluid has the potential to cause dental health problems but some protection against dental caries is provided by the calcium and phosphorus content of infant formulas as well as from the fluoride in the water used to make up the feed.

“Feeding caries” can result from misuse of diluted fruit juices and high sugar liquids when used inappropriately.

Duration and frequency of feeding are important factors in preventing dental caries and babies should never be left alone with a bottle and should be encouraged to drink from a beaker or cup as soon as they are ready to make the change. Bottles should never be used as comforters.

Infant formula labels include reminders about safe bottle feeding, but if concerned parents should also seek health professional or dental advice.

Further information about baby dental health can be found on the Australian Dental Association’s “Let’s talk baby teeth” site: