Did you know that your flour can go rancid? Neither did we. As it turns out, anything that contains natural fats (even in small amounts) will eventually go off. Armed with this surprising and slightly alarming information, we’ve opened the cupboard to learn all about the wild world of flour.

An airtight container is fairly common sense when it comes to storing flour, however where you store your flour can make a big difference to the precious kitchen staple’s short shelf life. 

Many of us already know to pop our new bags of flour into the freezer overnight to kill off any bugs (yes, they’re more than likely in there). But what’s news you may not know is that when stored at room temperature, your flour is best before around 6 months. 

If stored in the fridge, your flour can last up to a year. And if stored in the freezer, you can get up to two years out of your all-purpose.

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How can you tell if your flour has gone off?

When plain flour is off, it will often take on a pale yellow or grey colour. It can also develop clumps due to moisture and may take on a musty or sour smell. 

What happens if you use expired flour?

Depending on how far gone your flour is, the end result can have an unpleasant smell, a sour flavour, and in extreme cases, could make you sick. The texture of your final product may also be affected – if the flour has absorbed moisture while being stored, the flour particles won’t be able to take on the liquids you intentionally add. Hello, soggy cakes.

Exposure to moisture can also cause mould to grow on your flour and clumps to form. 

How long does flour last?

As a rule of thumb, of your flour is in an airtight container and free of pests, here’s how long your all-purpose flour can be stored:
In the pantry – 6 months
In the fridge – 12 months
In the freezer – 24 months

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