Unless you’re a professional pastry chef or an avid baker, chances are you purchase onebag of flour at a time and use it in relatively small amounts. But did you ever stop to wonder if that bag you just dug out of the back of the cupboard was fresh enough to use? Can you even remember when you bought it?Doesflour expire? For such a universalpantry staple, there’s a surprising amount of ambiguity about whether wheat-based flour goes bad. And while some resources may point to a use-by range of three to eight months, the reality isn’t so simple. Not to mention, that’s a pretty wide margin for error—and who wants to replace their flour every three months? To find out how long you can actually hold on to your flour stash, we turned to pastry chef and author ofMother Grains: Recipes for the Grain Revolution, Roxana Jullapat, and assistant professor of food science at Cornell University,Abby Snyder.
How long does flour last?
In short, longer than you’d think. According to Snyder, questions of food expiration come down to two factors: safety and quality—and safety isn’t much of a concern here. Flour is a low-moisture food, meaning it doesn’t contain enough water to support microbial growth. As such, it’s considered extremelyshelf stable and unlikely to become less safe to eat over time. And although flour may contain pathogens like E. coli, which can survive for long periods in storage, the risk in ingesting the flour won’t increase—but it’s certainly why we recommend heating flour before consuming it, like in our recipe forready-to-eat cookie dough.
Quality is less clear-cut, and Snyder typically avoids giving specific time estimations. But you can expect most refinedwhite flours (all-purpose,bread flour, 00 flour,cake flour, etc.) tokeep for a year or more if stored properly (i.e., kept dry in anairtight container in a cool, dark place). “I definitely have flour in my pantry that's over a year old,” Snyder says, “and it's fine.”
What about othertypes of flour?
Just like a bottle ofolive oil can turnrancid in your pantry, the fats in some flours can spoil. The hom*ogenous, highly refinedall-purpose flour commonly found in grocery stores contains less fat than somegluten-free flours, likebuckwheat flour,coconut flour, andnut flours, likealmond flour. Because of their higher fat content, these flours may be shorter-lived—in Jullapat’s experience,higher-fat flours can turn less desirable about two times faster thanall-purpose flour.
Forwhole wheat flour and otherwhole grain flours, likerye and spelt, the bran and germ (the parts of the kernel removed duringwhite flour’s refinement process) may cause fasterspoilage. These flours contain fats susceptible torancidity which can contribute to shortershelf life.
Self-rising flour, which containsbaking powder, is a special case. Snyder advises that while it won’t “go bad” by standard definitions, the leavening agent could become less potent over time.
No matter what variety you're concerned about, Snyder assuages that, by and large, theshelf life of flour is extensive. She also says that it's not reallyfood safety you need be concerned about but quality deterioration, which she posits is “somewhat subjective.”
