• Firstly, read the can preparation directions for the formula you are using.
• The guidelines in Australia and NZ and the Standards are to wait until the boiled water is cooled to around body temperature of around 37°C, which should feel warm when tested.
• If the water is used while too hot there is not only a risk of burns to you and the baby, it can also reduce the level of essentials vitamins and any probiotics in the formula.
• Most formula powders mix better when the water is still warm rather than cold. It is important that the powder is mixed properly to ensure that optimal nutrition is being given to your baby.
• Note that other countries may advise mixing formula powder with very hot 70°C water. This is not the recommendation in Australian or NZ Guidelines and the Standards for labels. So do not get confused if you read this in books or internet information from other countries like the US or UK. There are also formula making machines available in Australia that do a 70°C hot shot of water with the formula powder.

• Although it might take a little extra time it is important to always be as accurate as you can when measuring the water. Particularly, when you have a younger infant or one that is having health problems.
• This may sound really obvious, but always check and follow directions for water-to-powder ratio on the formula can label you are using.
• The formula powder dilution is carefully designed to provide nutrition at levels found in breastmilk. Note the proportions vary between different formulas depending on the powder and scoop size. Changing the relative amounts of water or powder can cause your baby to get sick from electrolyte in-balances, dehydration or constipation. A healthcare professional may advise adjusting dilution due to your baby’s health problems and this is the only circumstance when you should vary from the label directions.
• Many baby bottles provide indicators every 10mL in-between main marked number measurements. Count any smaller indicators between main measurements, to check.
  Example: the bottle provides markers at 120mL and 150mL and has 3 evenly spaced dots inbetween. These dots would therefore be for every 10mL indicating 130mL, 140mL & 150mL.
• To be super accurate (which is normally not required) ensure the water is level with the indicator when you are eye level with it.

There are a number of ways to warm and cool water to try and get the right temperature quickly.

Cooling water that is too hot:

• Place bottle of hot water under running cold water tap.
• Place bottle of hot water in container of cold or even icy cold water.
• Wrap bottle of hot water in a wet cloth and place in freezer.

Kettle or instant hot water dispenser:

• After boiling water leave the water to cool for at least 30 mins and check. The temperature achieved after this time will vary depending on the volume of water boiled, the room temperature and kettle. If you do this regularly try to set a routine of boiling the same amount of water and then set a timer for the approximate time it takes to cool to the desired temperature.
  Example 750ml boiled water took 30mins to cool to 45°C. Then it can be used it directly to make a bottle and stored the rest in a thermos for later.
• Some kettles and instant hot water dispensers allow you to set temperatures to keep water warm.

Keep water warm in thermos:

• Warm safe water can be stored in the thermos to use.
• If using a thermos, ensure it is thoroughly cleaned inside. It is best to just use it only for water to reduce the potential of it getting dirty.
• It can be sterilised with anti-bacteria solution (e.g. Milton tablets or fluid), or you can rinse with some boiling water.
• As a rough guide use about 2 parts boiling water to 1-part pre-boiled fridge temperature water. Or 1.5 parts boiling water to 0.5 parts room temperate water.

Microwave:

Heating just water in the microwave (not formula) is possible, however it must be safe:

• Only heat in a microwave-safe container like a glass bottle.
• Ensure the water is mixed thoroughly after heating so there are no hot spots.
• Test the temperature of the water on your hand or with a clean thermometer.
• Only add formula powder to water when it is at a suitable temperature.
• The amount of time needed to heat the water will depend on the temperature of the water beforehand, the microwave power, the amount of water and the container it is in.
• Get a routine so that you learn how much water and time in the microwave are needed to get the perfect temperature. Start with small 10 second increments until the desired temperature is achieved.

Measuring the right amount of formula powder is important. The formula and dilution ratio is carefully formulated to meet regulations and reflect the nutrition levels found in breastmilk. Incorrect measuring of the powder or purposely deviating from the label guide can lead to issues like electrolyte in-balances, dehydration or constipation. A healthcare professional may advise adjusting dilution due to your baby’s health problems and this is the only circumstance when you should vary from the label directions.

To measure the right amount of formula:

• Use the scoop provided with the formula can.
  Never use a scoop from a different formula tin, such as from a different brand or stage, because the scoop size varies depending on the formula and proportions required.
• Follow Label Directions.
  Adhere to the feeding guide on the can for the recommended powder-to-water ratio.
• Ensure a full but not packed scoop.
  Fill the scoop with powder, ensuring it’s full but not compressed (you’re not making an expresso).
• Precisely Level Off the Powder.
  Many formula cans have an inbuilt lip to facilitate levelling off the powder. If not, use a clean, dry knife for precise levelling.
• Optional Check Weight of Grams per Scoop
  Every formula label indicates the grams of powder in one scoop, so it is possible to check. If you have scales that measure accurately to 0.1g, you can verify the weight. Ensure the container on the scales is clean and accounted for. Note that some household scales may be inaccurate, so use a reliable device.

Always pour water in first, for two main reasons:

• Firstly, as it means you can measure the water accurately when using the bottle measurements.
• Secondly, this also helps with dispersion of power in the water & prevents the powder clumping on the sides or bottom of the bottle.

Thorough mixing of formula powder in the water to a “milky consistency” is important to ensure your baby receives the necessary nutrition.

Mix the powder into the water thoroughly to eliminate any lumps by:

1. Adding the Powder After Water: To minimise clumping on the bottom and sides of the bottle, add the powder to the water, as mentioned above.
2. Tapping and Swirling: Beginning by tapping and swirling the bottle helps to initiate the dispersion of powder into water. This step helps kickstart the mixing process.
3. Shaking Carefully: Shake the bottle, ensuring the lid is securely fastened.
4. Checking for Smooth Consistency: Once properly mixed, the formula should have a smooth consistency resembling milk, with no visible lumps of powder.

• Swirl or Stir: Instead of shaking, opt for swirling or stirring the formula. While this method may take longer, it ensures thorough mixing without excess bubbles.
• Tapping: Tap the bottom of a bottle against the bench to help force bubbles to rise to the top, facilitating their removal.
• Allow Time to Settle: Let the formula sit for a bit before feeding to allow some time for bubbles to dissipate. Even a few minutes will help, or leaving in the fridge for a few hours.

Yes, you can make formula in bulk. However, it is recommended to make formula individually rather than in bulk.

Recommendations:

• The Australian Infant Feeding Guidelines recommend preparing only one bottle at a time, just before feeding. This is because it is safest for formula to be made just before using, as bacteria does not have time to grow. Additionally, preparing bottles individually ensures accuracy in accordance to the feeding guide on the formula label.
• The labels of formula also advise that each bottle should be prepared individually, in accordance to the labelling standards.

Consideration if Making Formula in Bulk:

While not recommended, some carers opt to prepare formula in bulk often using a pitcher for convenience.

• Maintain Correct Dilution: It is crucial to maintain the correct powder-to-water dilution ratio specified on the label. This may require careful calculations. If unsure, consult a healthcare professional or contact the customer enquiry line of the product for guidance.
• Ensure it is Refrigerated Correctly: Any prepared formula kept in the fridge must be used within a 24 hours period. Therefore, ensure that the amount made will be used within this time. Please also see section on “FAQ Can I keep prepared formula in the fridge” for information on refrigerating formula.

Immediate Use is Recommended:

• To prevent bacterial growth, it’s safest to prepare formula as needed.
• Bacteria Growth Considerations: The longer formula is warm, the more time harmful bacteria have to multiply in the formula.
• Special Considerations: Particular caution is needed with pre-term babies, all younger infants under 3 months old and babies with a weakened immune system.

Recommended Timeframes:

• Australian Guidelines: As per the Australia Infant Feeding Guidelines, formula should be used within 1 hour of preparation if not promptly refrigerated. Any unused formula beyond this time should be discarded.
• New Zealand Guidelines: According to the NZ Healthy Eating Guidelines, formula should be consumed within two hours of preparation if not promptly refrigerated. Discard any remaining formula after this period.

Yes, prepared formula can be stored in the fridge for up to 24 hours. However, there are extra considerations to be aware of when doing this. Below are guidelines and safety measures that are essential to follow.

The Australian Infant Feeding Guidelines and NZ Healthy Eating Guidelines and the standards for labelling advise that this is safe and possible to store formula in the fridge for 24 hours, with the following considerations:

• It is always safer to make the formula when it is needed and use as soon as possible, because bacteria do not have time to grow.
• Before storing formula in the fridge it is best to ensure that it is working properly and cooling to between 0°C and 4°C by getting a fridge thermometer. Canstar Blue have a good detailed article covering fridge temperatures here
• Immediately refrigerate freshly prepared formula, placing it on the bottom shelf at the back, the coldest part of the fridge.
• Do not store formula in the fridge if it has been at room temperature for over an hour or if your baby has consumed some. Introducing bacteria from the baby's mouth accelerates spoilage.
• Formula stored in the fridge must be used within 24 hours of being made. To track, note the date & time by a sticker on the bottle, note clipped to the front of the fridge or a note book (e.g. feed tracker).
• Discard any remaining formula after 24 hours, as bacteria will still grow, just at a slower pace than at room temperature.

• While babies can safely consume milk at room temperature, many prefer and accept warmed milk more readily.
• Experiment with milk at room temperature or even cold from the fridge (probably more likely in warmer weather and when baby is a bit older), to see what your baby prefers.
• Not warming formula or warming it only slightly can save time and effort.
• Note that formula usually mixes best when the water is warm, as specified in the direction on the label. However, this does vary among different products, so a little experimentation here will quickly inform you on what is viable.
• Specialty formulas, such as thickened formula for reflux, may only be able to be used warm to maintain consistency and prevent separation.

1. Hot Water Method
• Place bottle in a bowl of hot water until warm (which should take less than 10mins).
• Alternatively, run hot water from the tap over the bottle until warm.
• Always test the temperature of the milk before using by dropping some milk on your inner wrist to check it is lukewarm and not hot. A baby’s mouth is very sensitive, so burns more easily.
2. Bottle Warmers
• Normally take about 10 minutes to warm milk up to an exact temperature.
• Some wrap around the bottle to warm it up, while other make direct contact with the milk and therefore need to be cleaned.
3. Microwave

Using a microwave to heat baby’s milk once it is made is not recommended due to several risks and considerations.

Risks of Microwave Heating:

• Uneven Heating: Microwaves heat unevenly, leading to hot spots in the milk. These hot spots can scald your baby’s sensitive mouth and throat, even if the temperature seems appropriate.
• Loss of Nutrients: Overheating in the microwave can result in loss of essential vitamins and probiotics in the milk.
• Potential Contamination: Not all plastic bottles are microwave-safe and some may release harmful particles into the formula or water.

Considerations if Using a Microwave:

Despite the recommendation against microwave use, some carers still opt to use it. If you choose to do so, take precautions:

• Heat the milk gently on a lower power setting for small time increments.
• Shake the formula well after heating to ensure distribution of heat and eliminate hot spots. Note that clumped powder and fat can mean that even after shaking, hot spots remain.
• As always, test the temperature of the milk on your wrist before feeding to ensure it is lukewarm and not hot.

• Refer to the label on the formula tin for specific storage instructions.
• Unless you're travelling and need to reduce volume, it’s best to keep the formula in its original container for cleanliness and safety.
• Store the formula powder container in a cool, dry place, such as the pantry or a food cupboard.
• Ensure scoop is clean & dry before putting this back in the tin. Always promptly return scoop to the can after use and try to not place on the bench or elsewhere. If the scoop gets wet or dirty, clean and dry it before returning to the can.
• Immediately cover the container with its lid after use to prevent contamination.
• Do not store in the fridge, as moisture can be introduced to the powder.
• Avoid water getting in the powder.

• The can or container of powdered formula specifies a recommended duration for using the product once opened, usually around 3-4 weeks.
• For those who only use small amounts due to mixed feeding, marking the opening date on the can helps track usage.
• Exposure to air after opening can lead to faster degradation of essential vitamins and fats like omega-3 in formula powder. However, products are formulated with sufficient vitamins to ensure minimum levels are maintained under normal storage conditions.
• Nutrient degradation is most crucial for infants under 6 months, as formula may be the sole source of nutrition.
• For those who occasionally mix feed, some brands offer sachets as an alternative convenient option.

It's not recommended to use any product past its Use-By date, as advised by food authorities and manufacturers.

• Essential vitamins and fats like omega-3 degrade over time, affecting both nutrition and taste. Other nutrients such as minerals are not impacted over time.
• Companies do rigorous testing to ensure that the products’ nutrition are meeting the necessary nutrition before the Use-By date.
• Check the Use-By date when purchasing in bulk or specialized products. Typically, it is found on the bottom of the can.
• It is against Food Safety Laws for a product to be sold after a Use By date, however it can be sold just beforehand.
• Be mindful when shopping at smaller regional pharmacies or for specialty products, as they may have been on shelves for an extended period.
• Despite some nutrient degradation in some vitamins & fats, if the tin can is unopened there's no increased food safety risk from bacteria in the powder across the shelf life or even after the Use-By date. Although, formula powder is not sterile it must meet tight regulations and be tested for microorganisms (e.g. bacteria). The tin is completely sealed and this along with the low moisture and oxygen in the powder ensures it is safe.

• There is faster degradation of nutrients if stored in hot environments.
• Products can be exposed to hot environments for extended periods of time when stored in warehouses or transported around the country or internationally.
• Companies do rigorous testing to ensure that the product’s nutrition is meeting the necessary levels before the Use-By date given likely storage conditions.

If a sealed tin is in the heat for a short period of time this is not a concern (e.g. left when delivered for a few hours on your door step on a hot day)

• There's no official recommendation regarding this.
• Normally powder in a dispenser container is exposed to more air, light, and moisture compared to the original can, which will lead to faster degradation.
• Therefore, the standard 3-4 week guideline advised on can labels after opening doesn't apply to powder put in a dispenser container.
• Ideally, use powder from a dispenser within a few days to prevent degradation, rather than storing it for weeks in a baby bag.

Locating the scoop in a container of formula powder can sometimes feel like a challenging treasure hunt.

• Use Clean Dry Cutlery: To help sift through the powder and dig it up. Make sure your hands are clean and dry too.
• Scoop from the Same Product: If you have previously used the exact same type of formula (e.g. same brand, stage, label etc.) then it will have the same size scoop (note the scoop size is included on the label & can be checked), which you can use until you find the new one.
• Scales: A set of scales which accurately measures to the nearest 0.1g can also be used to measure the amount of powder instead of using a scoop. Note some household scales can be inaccurate, so ensure you are using a device you can rely on.

Yes, because baby’s immune system is still developing and therefore, they are more vulnerable to any bacteria or other micro-organisms. A younger baby that is under 3 months or having health problems is particularly vulnerable.

Recommendation:

• Formula labels and Australian Infant Feeding Guidelines recommend boiling tap water until the baby is 12 months old.
• NZ Healthy Eating Guidelines recommend boiling public tap water until the baby is 6 months old and private water (eg. tank water) until the baby is 18 months old.

Note, boiling only removes bacteria and other microorganisms, it doesn’t remove other contaminants that can get in the water. Examples include nitrates and lead. Do note that levels of these would normally be very low, with negligible risk to the baby if consumed.

Public tap water (e.g. city or urban) after boiling is recommended as safe to use for baby.

Considerations for public water:

• Public water is filtered and treated, normally with chlorine, to be safe for everyone.
• Public water is regularly tested at the water treatment station, and normally councils publish test results on-line. The test results are compared against public water standards for compliance and safety.
• Despite this thorough process and testing, public water may on rare occasions contain a microorganism like e-coli. This is why boiling tap water for babies is advised.
• Also, note that contamination from pipes is also possible after it leaves the water treatment station (e.g. lead from house pipes). It is best to avoid using water that has been sitting a long time in the household pipes (e.g. first thing in the morning) for making formula. Running the water tap for 10-15 seconds can reduce any contaminants that have leached from house water pipes.
• It is also possible to get in-home water testing kits to check water from your own taps, however this obviously takes time & money.
• Fluoride is also normally added to most public water in Australia and New Zealand. However, babies without teeth do not need any fluoride. Breast milk contains none to very low levels of fluoride and formula powders must not contain any added fluoride. The level of fluoride in public water is significantly higher than the levels found in breastmilk.

Private water (e.g. rural tank water) varies considerably and is sourced from many different places (e.g. rain, bore, streams) and then transported, stored and maybe treated.

Considerations for private water:

• As it is not continuously monitored, treated & tested like public water there is more risk that the quality & safety many not be the best.
• Water quality and safety should ideally be tested and checked.
• Contamination can come from many different sources.
• Lead paint on the roof of the house for rain water.
• Dirty gutters (e.g. bird faeces, dead animals or rotting vegetation)
• Pesticides, fertilisers or animal faeces leaching in the soil for bore or stream water.
• Dirty water tanks.
• Pipes.
• Similar to public water, contamination from pipes is also possible after it leaves the water tank and any treatment such as filtering. It is best to avoid using water that has been sitting a long time in the pipes (e.g. first thing in the morning) for making formula. Running the water tap for 10-15 seconds can reduce any contaminants that have leached from house water pipes.

This depends on where you are getting your water and personal preference. Using safe water is important, as babies are particularly vulnerable to any contaminants. Baby’s rapid growth & development also means that they consume at lot more water relative to body weight compared to an adult. Their developing bodies are also not as good as adults in eliminating toxins. Public water is tested thoroughly and is recommended as safe after boiling, however there is no harm in filtering further if you wish.

Considerations for filtered water:

• Filtering tap water further can remove some more contaminants and minerals however, this is optional and not recommended by the Australian Infant Feeding Guidelines.
• Although, it can be argued the cost & time of filtering water is not worth it, particularly for public water, I hold the personal view the lower the amount of any non-beneficial contaminants in the water the better for baby. So, I definitely would be trying to get the purest water possible but do work within your budget.
• There is major variation in water filters available, and some may do very little. It is also important to change water filters regularly in accordance to manufacturers’ directions.
• Most waters filters won’t remove all bacteria or other microorganisms so boiling is still required.
• Note that the removal of any beneficial minerals from the water is not a concern, as the levels are minor. Formula powder is made to ensure necessary nutrition once reconstituted with water, which makes up for any possible deficit in the water.
• Alternatively, bottled water can be used rather than filtering. Note, only buy plain water (e.g. still, spring, purified or distilled) and never sparkling or soda water. And obviously bottled water will likely be the costliest option.

The Australian Infant Feeding Guidelines state “bottled water (but not sparking mineral water or soda water) can be used to prepare formula if unopened, but it is not necessary”