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Perfect prep and formula bottle prep machines

Find out if it's worth investing in a baby bottle prep machine such as the Tommee Tippee Perfect Prep Machine or the Baby Brezza Formula Pro Advanced 
Lauren TempleSenior market analyst

Formula prep machines are marketed as a quick and easy way of preparing formula milk with feeds ready at the correct temperature in minutes. 

They claim to simplify the process and are an attractive prospect for sleep-starved new parents, especially considering newborn babies need to be fed at least 8-12 times every 24 hours, but are they worth investing in?

Below we explain how prep machines work, their key features and take a look at NHS guidance as well as key concerns about whether they are safe to use. Plus, where to buy them if you want compare prices at key retailers.


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What is a bottle prep machine?

Prep machines are intended to make formula bottle feeding quicker and easier than the standard kettle method.

Manufacturers claim they can produce formula feed at the correct temperature and consistency within minutes, meaning you don't need to faff around or wait for the formula to get to the right temperature. 

Simply choose the amount of formula you want to be produced and the machine dispenses a hot shot of water above 70°C that kills any bacteria in the formula and helps to dissolve the powder. Then cooler water is added to produce a bottle at body temperature that you can feed to your baby straight away.

Some prep machines are designed slightly differently and boil water like a standard kettle, then quickly cool the boiled water to 70 or 40˚C, or keep it heated at a set temperature for making formula later.

As always, you'll need to test the temperature of the formula on your wrist before feeding your baby.

Make sure to follow the manufacturer guidelines in terms of cleaning and maintenance if you own a prep machine. Run the cleaning cycles often, change the filter when needed, and it's advised to regularly flush sterilising fluid or boiling water through the pipes of the machine.

The most popular prep machines include the Tommee Tippee Perfect Prep Machine (£165), Baby Brezza Formula Pro Advanced (£260) and Babymoov Milky Now Bottle Prep Machine (£80). We've rounded some of the most popular retailers further down the page and below we go into detail about some of the concerns.

Does the NHS recommend prep machines?

Some NHS Hospital Trusts do not recommend using prep machines. This is because some models do not heat water at a high enough temperature (70°C) to kill harmful bacteria and germs. 

Dr. Vicky Sibson, director of First Steps Nutrition Trust explains, 'There are many different baby formula preparation and feeding devices on the market, designed and advertised to make life easier when bottle feeding hungry babies who just can’t wait, or who need a feed in the middle of the night. The marketing typically seeks to reassure parents that these gadgets are safe and adhere to NHS guidance.

'Unfortunately a lot of the time such claims are not true, or there is a lack of evidence available in the public domain to be sure. It’s important that parents/carers who bottle feed their babies understand the NHS guidance and the risks to their baby’s health it seeks to address. We would advise parents to talk to their midwife, health visitor or GP if they want more information so that they can make a fully informed decision about how they make up their baby’s bottles knowing the risks of different ways of doing this, especially if they choose to use a device.'


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Concerns around formula bottle prep machines

Newborn being fed with a bottle

If the water is not at least 70°C when added to the powder, any bacteria intrinsic to the formula powder will not be killed. Some prep machines require you to decant the powder in to the machine so that it can be mixed with the water internally, and this also creates extra risks of contamination.

In addition, some machines repeatedly boil water and this concentrates elements, which again is not safe and against NHS advice that fresh water should always be used when preparing powdered infant formula.

A study by Swansea University revealed that 85% of the 74 Perfect Prep Machines tested by parents in UK homes did not appear to produce water that would be hot enough, and this could pose a serious risk to infant health.

If you have any concerns about your prep machine you're advised to buy a food thermometer and test the temperature of the hot water that comes out of the machine. Do not use this tested water in a feed due to potential contamination. 

If the temperature is below 70°C, do not use the machine to prepare infant formula and contact the machine manufacturer. We recommend following the NHS’ step-by-step guide on how to prepare formula feed.

For further information on this, take a look at the First Steps Nutrition Trust's advice on infant milk safety and the best way to prepare formula for your baby.

Can you use any type of formula milk with a prep machine?

Prep machines should be compatible with all types of formula milk. 

Tommee Tippee says their machine works with any brand of powdered formula milk while Baby Brezza says their machine works with virtually all formula brands.

If you're using a specialist baby formula it is worth checking with the manufacturer to confirm that it is suitable.

Can you use any bottles with a prep machine?

Key brands claim to work with any brand of baby bottle. 

Baby Brezza says their machine works with virtually all bottle brands and sizes, while Tommee Tippee says its machine has an adjustable base that's designed to accommodate different bottle shapes and sizes. 

Double-check the specification details of the prep machine before purchasing to make sure your bottle is compatible.


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How long can you keep a bottle made by a prep machine?

Formula milk should ideally be made when needed to reduce the risk of infection. The NHS advises parents to use formula stored in the fridge within 24 hours. 

If it’s stored in a cool bag it should be used within four hours and if it’s stored at room temperature it should be used within two hours. 

There are a number of portable products available to help with preparing formula milk on the go. 

The Tommee Tippee GoPrep and Nuby RapidCool Portable Baby Bottle Maker claim to cool fresh formula feed to the right temperature in two minutes. 

Alternatively there are lots of portable bottle warmers to choose from, which will heat up pre-made formula bottles.

Where to buy a prep machine

There are plenty of retailers to choose from, below we round up five of the most popular high street brands and online retailers. 

Whether you're shopping online or in-store, make sure you pay attention to the shop's returns policy. 

  • Amazon has a wide range of prep machines from recognisable and more niche brands, starting from £85.
  • Argos sells prep machines from Tommee Tippee and Baby Brezza with prices ranging from £165 to £250.
  • Boots offers prep machines from Babymoov and Tommee Tippee. Prices start from £80.
  • John Lewis customers can pick between the Tommee Tippee Perfect Prep Day & Night and the Baby Brezza Formula Pro Advanced and Formula Pro Mini. Expect to spend between £100 to £240.
  • Online4baby.com has a big range of Tommee Tippee bottle feeding products starting from £95.

Not sure what you do and don't need? Read our expert advice on buying baby bottles, sterilisers, warmers and other feeding essentials