Flour is a kitchen staple for baking delicious treats, coating chicken cutlets, thickening sauces and more. But if you’re anything like us, that giant package of AP that dip into every couple of weeks been hanging out in your pantry for a looong time. (Not to mention the whole wheat variety, which only gets pulled out once every six months.) So, does flour go bad? Good news: Although flour won’t stay fresh forever, it does have a pretty impressive lifespan. Here’s what you need to know before you grab that ancient bag of flour from your pantry and start putting it to good use.
Does flour go bad?
Indeed, it does. All types of flour have some degree of oil in them and, as such, they can go rancid over time. However, the question of how long it takes before spoilage sets in does not have a one-size-fits-all answer. The shelf-life of any flour has a lot to do with its source—and wheat is not the only one out there. That’s why we went straight to the experts behind FoodSafety.gov to find out what to expect when it comes to keeping flour fresh.
How can traditional flours last in the cupboard?
White flour: Of all the different types of flours, the classic stuff is the most shelf-stable. All-purpose flour can last six to 12 months from the date of purchase when stored unopened in the pantry. If you opened your all-purpose flour and returned it to the pantry, you can still count on six to eight months of freshness, but the refrigerator is a much better option in this scenario: All-purpose flour that has been opened will still stay fresh for a full year when stored in the fridge.
Whole wheat flour: Unfortunately, the healthier option has a shorter shelf-life. Whole wheat flour is a more nutritious product because it is made from the entire wheat kernel, whereas white flour contains only the endosperm of the wheat. However, that whole kernel contains more oil than what you find in the endosperm alone, and oil can go rancid. As such, you can expect whole wheat flour to last in the pantry for three to six months after you bring it home from the store, or six to eight months in the fridge. (Note: These guidelines are the same regardless of whether or not the package has been opened, assuming that the contents haven’t come into contact with water.)
And what about gluten-free flours?
There are many varieties of flour out there, and though wheat flour is the most commonly used, it is strictly off-limits for anyone following a gluten-free diet. So how do the most common kinds of gluten-free flour stack up in terms of staying power? Alas, none of them hold a candle to wheat flours in this regard, so you’ll have to make relatively short work of them (i.e., use ‘em up within a couple of months). Here’s how long you can expect some of the most popular gluten-free picks to stay fresh, according to both FoodSafety.gov and the Whole Grains Council.
Brown rice flour: This is one of the most popular and versatile gluten-free flours around and it boasts almost as long a life as its wheat-based counterparts. The only catch is that proper storage conditions are critical here: Brown rice flour requires chilly storage temperatures—so don’t stick the stuff in your pantry. Instead, store brown rice flour in the fridge for up to five months of freshness or in the freezer for a full year.
Buckwheat flour: A nutritious and earthy-tasting gluten-free alternative to wheat flour, buckwheat has the shortest shelf-life of the GF bunch. Buckwheat flour will keep in the pantry for only one month from the date of purchase and, sadly, the fridge doesn’t buy you any more time. However, the buckwheat stuff will stay fresh for up to two months in the freezer, so that’s your best bet for making the most of this flour.
Coconut flour: This may not be the most widely used gluten-free variety, but considering the growing cult of coconut fans, it’s probably going to become the next big thing soon enough...and that’s good news for anyone fretting about the freshness of their flour. It turns out that coconut flour has the longest lifespan of them all: This type of flour will stay fresh in the fridge or the freezer for nine to 12 months—but take a hard pass on pantry storage since coconut flour is not shelf-stable.
Amaranth, sorghum and oat flours: These popular gluten-free flours can all be stored in either the pantry or the freezer. (Yep, forget about the fridge—it won’t do you any favors.) These types of flours will last for up to two months at room temperature, but freezing doubles their shelf-life, providing up to four months of freshness.
How to tell if your flour has gone bad
The easiest way to know if your flour has gone rancid is to give it a good sniff. While most flour has practically no odor, spoiled flour will smell stale, musty or even sour. It may also look discolored. And if your flour has come into contact with water or moisture (say, because you used a wet measuring cup to scoop out the stuff the last time you baked) then clumps of mold may appear. If you see mold inside the bag, then you should discard the whole thing immediately.