It’s safest to make up formula when you need it following the usual gold standard technique as recommended by the NHS.

However, even though formula prep machines are not advocated, they remain widely used and highly rated by formula feeding parents.

If you choose to use a formula prep machine, it’s really important you follow the instructions to the letter and are rigorous about maintenance and cleaning.

How do formula prep machines work?

The main formula prep machine on the UK market works by measuring the water to make up the required amount of formula at the perfect temperature for feeding straight away. This means you can make a ready-to-feed bottle in less than a couple of minutes which explains the popularity of these machines!

To make a bottle, add the required number of formula scoops to the bottle and then the machine will dispense a ‘hot shot’ of hot water - 70 degrees C - to mix the formula powder in. Make sure all of the powder is completely dissolved in this hot shot to ensure any bacterial contamination in the powder is taken care of. Recent research has shown that not all formula prep machines manage to reach the required 70 degrees. We recommend, as per the iHV, to check the temperature with a thermometer of the dispensed water. If it is not at 70 degrees or over, then use the standard method of preparation.

The bottle should then be placed back in the machine which will top it up with the correct amount of water at the specific temperature to ensure the milk is ready to feed.

As always, it’s a good idea to mix the milk gently to avoid any hot spots and test the temperature on your wrist before feeding to your baby.

How do you clean and maintain a formula prep machine?

Follow the manufacturers guidelines for cleaning and maintenance.

Run a cleaning cycle often; it’s recommended to run sterilising fluid and/or boiling water through the machine regularly.

Ensure you only use the filters designed for your machine. While other, generic brand filters are available they will not have been tested with your machine so their safety and accuracy cannot be guaranteed. This can also lead to carbon from the filter building up in the pipes of the machine.

Open the back of the machine to check the water tubes.

What are the concerns about using formula prep machines?

Whilst the manufacturer states that the water in the hot shot is dispensed at over 70 degrees, there are concerns that the temperature may not be accurate and that the hot shot may not be dispensed in enough volume to sterilise the formula powder. There have also been questions about the accuracy of the final volume of water dispensed.

Some parents have been worried about build up of what appears to be mould in the water pipes of the machine. However, the manufacturer states that this is most likely to be carbon residue from the filter - which underscores the importance of only using the filter designed for the machine - and that a strict cleaning protocol will prevent this from happening.

If the handiness of a formula prep machine does appeal to you, we recommend that you read all of the information on he particular band you want to purchase. If you do buy one, make sure you put a strict cleaning and maintenance regime in place which includes running sterilising fluid through the machine and taking the back off to check the pipes on a regular basis.

Here’s what we found when one of us took the back off our formula prep machine.