Does Flour Go Bad? Here's What A Nutritionist Wants You To Know

Considering flour is the base of pretty much every baked good out therefrom bread to cake to biscuits to pastait's a valid question.

And, sadly, flour actually has a shorter shelf life than you think. In other words: Yes, flour can go bad, says nutritionist Molly Knauer, RD, advisor for Love Wellness .

Thing is, you likely wont know if your flour is expired just by looking at it (it doesn't get moldy or stanky right away). Plus, if you store your flour in some sort of container, you can't exactly see the expiration date on the bag.

Before busting out your measuring cups and firing up the oven, here's everything you need to know about when flour expires, how to store it properly, and more.

What is the typical shelf life of flour?

The good news: Regular all-purpose flour lasts a very long timeone year at room temperature and two years in the fridge or freezer, Knauer says. Same goes for other white flourslike self-rising flour, white bread flour, and white cake flourand "white" or processed flours made from starches like potato or tapioca.

Whole-wheat flour, on the other hand, actually has a shorter shelf life. The reason: Whole-wheat flour still contain's the grain's bran and the germ, which are rich in fiber and other nutrients but spoil faster. As a result, whole-wheat flour keeps for up to three months at room temperature, and up to a year in the fridge or freezer. Same goes for oat flour and other whole-grain flours.

What about high-fat flours, like almond and coconut flour?

Unfortunately for all you paleo bakers out there, the fat in popular alternative flours like almond flour and coconut flour makes them spoil more quickly than starchy flours.

Almond and coconut flours have a shelf life of just three months at room temperature and six months in the fridge or freezer, Knauer says. The same goes for other nut flours, and finely ground seeds (like flax).

What's the proper way to store flour?

Like many pantry staples, flour lasts longer if its not exposed to circulating air.

The best way to extend the shelf life of flour is to store it in an airtight container or sealable freezer bag at room temperature, or, even better, in the fridge [or freezer], says Knauer. Colder temperatures literally slow down molecules, which slows the breakdown (and eventual spoilage) of food.

Since flour needs to be at room temperature when you need it (because #bakingscience, guys), store enough flour for regular use in your pantry.

If you have more flour than you'll use within its shelf life, though, store some in an airtight container or bag in the fridge or freezer. Just be sure to take it out and let it come to room temperature before you use it, Knauer recommends.

How can you tell if flour has gone bad?

First things first: Every bag of flour has a use-by or expiration date printed on it. If youre transferring flour to an airtight container before stashing it away, label your container with that expiration date before throwing away the flour's original packaging.

Beyond that, theres one simple way to tell if flour is beyond its expiration date: Smell it!" says Knauer.

"Flour should have no smell, or a minimal nutty or sweet smell, she says. When flour has gone bad it has a more sour or playdough-like smell. (Ew.) Though the scent is typically fairly subtle, you should be able to pick up on it.

Pro tip: Make a habit of smelling your flour as soon as you open it, so you know what its supposed to smell like. That way, itll be easier to tell when it smells off.

So, can eating expired flour make you sick?

Raise your hand if you're reading this and thinking, Oh no, Ive been baking with flour thats been in my cabinet for years!

If so, dont worry. Eating expired flour generally doesnt have significant consequences. Most of the time, nothing happens other than that your baked goods don't taste good, Knauer says.

However, there is a small chance that eating expired flour might make you sick. If rancid flour contains large amounts of mycotoxins, it can make you sick, explains Knauer. ( Mycotoxins are toxic compounds produced by certain kinds of mold.)

Luckily, flour with that much mold would likely have a strong sour smell that would hit as soon as you opened the container, so you'd probably chuck in pretty quick.

The bottom line: White flours have a long shelf life (one year at room temperature) and should be stored in airtight containers. Spoiled flour will smell slightly sour, but eating it typically doesn't cause any real harm.