How Long is Baby Formula Good for Once Mixed? Plus, other Important Questions

Baby formula
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Let’s talk about baby formula today!

There’s always that time in the life of a parent when you’re so tired that you operate like a robot. Your newborn falls asleep while you are bottle-feeding it. You drop the bottle groggily and head to bed for – ten minutes or thereabouts.

Baby wakes up and starts shrieking. She needs feeding and you’re wondering whether to continue with the old feed in the bottle, after all, it’s been only five, wait, 65 minutes since you left it there. Is the formula still good?

This is only one out of the many scenarios where you might be faced with a question about baby formulas – but there are plenty of others – so, if you’ve been confused about formula rules, understand that it is not only you. Now, let’s settle some of these questions about formulas once and for all.

Read the instructions on the packaging!

This article will highlight some guidelines about the formula, but always read through the packaging for specific guidelines on storing, mixing, and general usage instructions. Instructions may vary slightly among brands – and sometimes within brands!

After preparing baby formula from powder, for how long does it remain good?

Once you’ve added water to your baby formula, the countdown begins. As a rule of thumb, the formula remains ok for up to two hours at room temperature, unheated and untouched.

But it is important to read up the instructions on the label – some manufacturers specify that it is safe for only an hour at room temperature once added to water. This depends on whether the manufacturer is following the guidelines by the Centers for Disease Control and Prevention or the American Academy of Pediatrics.

Does baby formula last longer when refrigerated?

Well, it does, as long as your baby doesn’t feed on the bottle.

A refrigerated bottle of unused formula can last up to 24 hours. This explains why a good number of parents prepare large amounts of formula in the morning and pour it into several bottles – for use all day.

These wise parents understand that a crying baby isn’t patient enough to wait for you to mix the stuff in a bottle.

The temperature of your fridge should be at least 4.4°C (40°F) or lower.

It is important to note that baby formula should not be freeze. If you freeze formula, the texture will change. Also, freezing doesn’t extend the “shelf-life” of the formula. If you are just getting started with formula after breastfeeding, then you should know that the guidelines differ in this and other aspects.

Does a partially used bottle of baby formula last as long as a fresh, untouched bottle?

Hell no! If the baby has fed from a bottle and is filled, don’t save the remnant in the fridge, discard it.

Milk products are fertile breeding grounds for bacteria. Once the baby has fed from a bottle, bacteria finds its way in, so there’s no need why you should save the bottle (for adults, this also explains why we shouldn’t drink from the milk carton).

Can I heat an unused portion and then store it in the fridge for later use?

You shouldn’t. We owe it to the bacteria. There’s no better place for the bacteria to grow in than a nice, warm environment.

An important point to note: if you’ve warmed a bottle, then the 2-hour guideline we gave doesn’t apply. Use up a heated bottle within an hour. Any leftover should be discarded. This applies to concentrates, powders, and ready-to-drink options.

What’s the shelf-life of an unopened, unused formula?

The good news is that you don’t have to write down the date you purchased the formula. Every formula comes with an expiration date. The date is mostly printed on the bottom of the sealed container. All sealed containers should be stored in a cool, dry environment. Also, do not expose it to extreme temperatures.