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What are bottle prep machines?
Bottle prep machines, also known as ‘baby bottle makers’, will either mix baby formula to the correct temperature or just boil water to the required temperature.
We know that the best method to feed your little one is to breastfeed for their first six months. However, not all mums can or want to and some decide to do combination feeding, which is a mixture of both breast and formula feeding. Infant formula is the only safe alternative to breastfeeding.
Different brands of baby formula need different amounts of formula added to the water before being given to your baby, so you should always follow the instructions for your particular brand of formula.
How much do bottle prep machines cost?
Other costs that need to be considered include changing the filters and running descaling cycles.
Things to consider when using a bottle prep machine
As with any type of bottle prep, it’s vital to clean and sterilise your baby’s bottle, teats and any other feeding equipment between feeds to protect your little one from infections, which could cause vomiting and diarrhoea. 
Your baby’s immune system is not as well developed as an adult’s. Sterilising all bottles and equipment reduces the risk of infection. 
Although you don’t sterilise a prep machine, you generally need to run a cleaning cycle before you first use it.
Tommee Tippee recommends that you run a cleaning cycle on a four weekly basis or if you haven’t used the prep bottle machine for a while. They also recommend running a cleaning cycle when you change a filter.
The Baby Brezza Formula Pro Advanced Baby Bottle Maker recommends descaling the internal sections of the machine on a monthly basis.
YXLONG does not provide very clear cleaning/sterilisation guidelines in English. They do state that the internal system is automatically cleaned to prevent the growth of bacteria.
Burabi states that their Smart Baby Formula Dispenser, with WiFi App control, has an auto clean function. They also state that the water tank, funnel and powder container are manufactured from food grade materials (Tritan Ex401).
Bottle prep machine manufacturers claim that the machines prepare the water to the exact temperature that you have set, every time it’s used. However, The Food Standards Agency has raised concerns about the 70°C hot shot of water that bottle prep machines release, killing potential bacteria in the infant formula. 
They’ve questioned if the small amount of hot water used will lose heat when released into the cold bottle and infant powder, meaning that the powder isn’t fully heated. 
This hasn’t actually been tested (or, if it has, data hasn’t been published), so we don’t know if this is what happens.
Using a bottle prep machine does save time on having to fill and boil a kettle. Time is saved with not having to wait for the boiled water to cool before you can add the milk powder.
Are bottle prep machines safe to use?
They are an independent public health nutrition charity made up of doctors and nutritionists and are referring to the fact that studies haven’t been done, so we don’t truly know whether they’re as safe as boiling the kettle.
Tommee Tippee launched an investigation into their machines after reported cases of babies becoming unwell from formula made by Tommee Tippee prep machines, which were found to contain mould in the filters. 
Tommee Tippee concluded that their machines were not to blame for these illnesses and that it is impossible for bacteria to enter the pipes when using a Tommee Tippee prep machine filter. 
Remember, the official advice is that you use cooled, boiled water at greater than 70°C to make up your powdered infant formula, and this is recommended by the Department of Health and the Food Standards Agency. 
Current guidelines for preparing baby formula
It’s important to make up each feed using boiled water at a temperature of 70°C or above. A kettle should be filled with at least 1 litre of fresh tap water and you should not use water that has been boiled previously. 
The boiled water should not be left for more than 30 minutes to ensure that it stays at a temperature of at least 70°C.
You should also make sure that you use the correct amount of water, following the manufacturer’s instructions. 
Always put the water in the bottle first, before you add the powdered baby formula.
The NHS guidance document helps you to prepare bottle feeds safely.
Formula at 70°C is too hot for your baby to drink and so you must allow some time for the bottle to cool before giving it to your little one.
Easier said than done when you have a hungry, crying baby, hence the popularity of bottle prep machines.
Why is it important to follow the guidelines?
Your baby’s immune system is not as fully developed as an adult’s. This means that babies are more at risk of getting very ill from food poisoning bacteria.
Powdered infant formula can contain bacteria that can cause illness, even when powdered infant formula tins are sealed. 
This risk of illness can be reduced by correctly preparing and storing infant formula and by practicing good hygiene when making up your little one’s feed.
Powdered infant formula must be stored in a cool, dry place.
What are the alternatives if you don’t want to make up bottles in the middle of the night?
Preparing a fresh feed every time one is required, and for your baby to drink it immediately, is the safest. The risk of infection to your baby increases over time. Bacteria can increase very quickly in a feed kept at room temperature, so please don’t do this. 
It is not recommended to make up multiple bottles of feed, even if stored in a fridge. Harmful bacteria can still survive and grow in a formula feed stored at cool temperatures. 
An alternative to making up feed at night time would be to buy cartons of ready made milk, which is sterile. This is a more expensive but, undoubtedly, a more convenient method for night feeds. 
Any unused ready-made formula needs to be stored on the top shelf at the back of the fridge (with the cut corner turned down) for no longer than twenty four hours before being discarded. 
The alternative for many is the convenience of the prep bottle machines.
Can all types of formula be made in prep bottle machines?
Bottle prep machines have been designed to be used with most powdered infant formulas. However, it’s best to follow the manufacturer’s instructions and guidelines regarding what powdered infant formulas can be used with your bottle prep machine.
Specialist prescription formula
It is best to ask your health visitor, midwife or GP about using a bottle prep machine, if your little one has been prescribed specialist infant formula. Prescription formula often needs to be made at a lower temperature and so a prep machine may not be suitable.
Baby formula tablets are very new to the UK market. Formula tablets can be used as an alternative to powdered infant formula, and they are sold as being safer as the exact amount of formula is pre-measured for you.
You can not use prep bottle machines for formula tablets. Bottles made up with tablets need to be made with boiled water from a kettle.
Are bottle prep machines worth the cost?
Personally, I think this is your decision to make. Some may feel that it’s worth taking the risk and others feel that it’s best to keep your baby as safe as possible.
However, having been an exhausted parent surviving on limited amounts of sleep, I can see the appeal!
Bottle prep machines available on the UK market
A review of the top 5 bottle prep machines
The Tommee Tippee Perfect Prep Machine is probably the most recognised bottle prep machine in the UK. It prepares baby formula bottles quickly and is very easy to use. It comes with a light that lets you know when the filter needs to be cleaned and also changed.
The Perfect Prep Machine does deliver a hot shot of water above 70°C when mixed with the formula powder which is then cooled to the correct temperature with cold water.
The initial ‘hot shot’ release of water destroys bacteria that might be in the powdered milk formula.
Releases the correct quantity of water which provides reassurance of a more accurately made up bottle.
Works with the majority of powdered formula milk.
However, the charity First Steps Nutrition Trust have raised concerns because the volume of water delivered in the hot shot is quite small and it can’t maintain its temperature for long enough to eradicate all bacteria in the formula powder. 
You are meant to add the formula within 2 minutes of the hot shot but this may result in formula powder being added to water that is lower than 70 ºC and the powder itself may reduce the water temperature.
This bottle prep machine dispenses baby formula from a compartment, which allows you to see when it needs to be topped up. You actually have to decant your powder into the machine, which unfortunately does increase the risk of contamination.
The Baby Brezza Formula Pro Advanced Baby Bottle Maker does not make bottles using water above 70°C when mixed with the formula powder and therefore is not considered safe by the NHS.
You do not need to buy replacement filters for it, which is a bonus.
The Baby Brezza website notes that the Formula Pro Advanced Baby Bottle Maker works with almost all types of bottles and formulas.
This bottle prep machine also dispenses baby formula from a sealed compartment, which also allows you to see when it needs to be topped up. However, it also introduces an element of potential contamination.
It has automatic heating, which allows the water and formula to reach the correct temperature in 10 seconds. It does not state, however, that the water is above 70°C when mixed with the powder, and so may not comply with NHS safety guidelines.
You do not need to buy replacement filters for it.
It does have an ‘Internal system’ for automatic cleaning and can be operated with just one finger!!
This gadget boils water in a tank and keeps it above 70°C using its ‘keep water hot’ function, so it’s always at the right temperature to mix formula.
The downside, however, is that water is repeatedly heated to maintain its temperature, which goes against NHS guidelines that state water should be freshly drawn to avoid concentrating elements.
You still need to wait for the formula to cool once prepped.
This gadget does away with the repeated boiling of the same water or the keeping water at a standard temperature. It has a heating system that heats water instantly instead.
You do have to decant the formula – opening up the risk of cross contamination, and tell the machine which formula you’re using. It knows exactly how much water to dispense, taking into account the differences between formula brands!
There’s no heating, mixing or shaking; this device does it all for you and is even controlled by an app! However, there is no mention on their website about the water being above 70°C nor how it cools the formula so quickly, leaving many unanswered questions.
Alternative product to prep bottle machine
This could potentially be the solution to all of the above listed worries. The manufacturer states that this portable bottle maker can cool boiling water to the correct temperature for feeding in two to five minutes, depending on the size of the feed. 
You fill RapidCool with boiled water that is above 70°C, add the required formula amount and mix well. The gadget cools the formula quickly, and you can dispense the feed into a sterilised bottle once the digital display shows the green logo.
Some of its benefits are:
It doesn’t require replacement filters.
It follows NHS guidelines.
It’s quiet, which is ideal for night feeds.
It’s easy to use and clean.
They’ve also developed a kit that comes with an insulator flask aimed to keep water hot for a few hours when you’re on the go. The thermometer lid can be transferred to the insulator flask to monitor the temperature of the feed.
Note that you must sterilise the digital lid with cold water or UV sterilisation and the base with cold water, UV, steam or dishwasher as they cannot go in the microwave.
Also, after being exposed to heat, the RapidCool needs 2 hours until it’s able to cool another feed.