Have you ever pulled out a two-year-old bag of flour and wondered if it was still good to use? As a recipe developer, I go through a bag of flour every few weeks, so I was wondering how long flour lasts and how the heck do I store it? Is there a way to know when things have gone bad? “I advise people to remember that flour is perishable — it’s not salt, it’s not sugar, and it’s certainly not inert. Take care of it,” says Martin Philip, an award-winning author, baker and baking ambassador for the King Arthur Baking Company. . If we take a closer look at the different types of flour, the grains themselves will help us find the answers.
All whole grains consist of three parts: the bran, the endosperm and the germ. The bran is the outer shell, the endosperm contains starch and protein, and the germ carries the genetic information of the grain and fat. That fat becomes rancid over time, so some flours are best kept cold, while others remain stable at room temperature.
White flour, including all-purpose flour, pastry flour, bread flour, and cake flour, uses only the wheat grain’s endosperm — which contains no oil — and does not require cold storage like other flours such as whole wheat or rye. Frank Tegetoff, a research and development specialist with the King Arthur Baking Company, recommends transferring the flour from the original paper bag to an airtight container, which keeps out moisture and insects. Whether your container is glass or plastic is up to you – just make sure the lid is tightly closed. Store the container in a cool, dry, and dark place such as a closet or pantry for up to a year.
Whole grain flour
Whole wheat flour uses the whole grain of wheat, including the bran and germ. The germ contains a small amount of fat that can turn rancid over time when exposed to oxygen. “Freezing slows that process down,” says Philip. While whole wheat flour can be stored in the pantry or on the counter for up to several months, shelf life varies based on factors such as temperature, humidity, and age. Storing whole-wheat flour in an airtight container or sturdy resealable plastic bag (Philip recommends double-wrapping) in the freezer will ensure that your flour lives past its best-before date.
Rye and other whole wheat flour
The same storage rules also apply to rye and all other whole-wheat flours. Store them in an airtight container in the freezer. And label them clearly, especially if you’re storing more than one type of flour.
Gluten-free flours can be divided into white and whole-wheat types.
White gluten-free flours include white rice flour, tapioca flour, and potato flour. These flours consist almost entirely of starch and contain no fats. When kept relatively cool and dry, these flours have an almost unlimited shelf life. Store these at room temperature in airtight containers.
Whole-wheat gluten-free flours include brown rice flour, sorghum flour, amaranth flour and oat flour. These should be stored like other whole wheat flours – in airtight containers in the freezer, where they will last at least a year. Like all whole grains, these contain fat that can go rancid over time at room temperature.
Polenta, cornmeal, grits and dough
Polenta, cornmeal, and any flour or meals made from corn kernels are best kept cold, preferably in the freezer. This is especially important for any corn product labeled “stone soil” or “whole grain,” as they contain the germ of the corn kernel. Sprouted corn products, which make up the bulk of major brand cornmeal and polenta, technically have a shelf life of up to a year, but experts agree that the freezer will keep them fresher for longer.
At this point, we know that fat, when exposed to the air, can quickly turn rancid. “A whole nut is nature’s perfect storage system,” Tegetoff said. “The more we make it easy to use and enjoy (peeled, chopped, ground), the more we take away the natural defenses and hasten its demise. With each refinement, more and more oils are exposed to oxidation.” Storing your nut flours in the freezer can help prevent rancidity and oxidation, at least until the expiration date.
“With this type of mix, the goal is to prohibit activation of the leavening agent(s),” Tegetoff said. Once opened, any leavening agents in a baking mix such as baking soda or baking soda should be kept cool and dry to maintain their full potency. He suggests transferring baking mixes to airtight containers or even resealable plastic bags and storing them in a cool, dry place (the pantry is fine) out of direct sunlight.
Whole grains and home-ground flour
Home milling has become more popular since the sourdough boom, and home sized mills produced by brands like Mockmill are gaining popularity. But how long can self-ground flour keep and how should you store it?
“Use it, don’t keep it,” says Dr. Stephen Jones, a professor and director of the Bread Lab, an extension of Washington State University. If you have the luxury of a grain mill at home, you reap the most benefits by using freshly ground flour sooner rather than later. If you must store it, let it cool before placing it in an airtight container. If you don’t want to use it within a few days, keep it in the freezer.
Unground whole grains have a much longer shelf life because the germ is well protected by the outer bran layer. Store whole grains in an airtight container in a cool, dry place for up to 5 years or in the freezer indefinitely. dr. Jones stressed that the most important thing with whole grains is to make sure they are clean, dry and free of insects before sealing them for long-term storage.
How do you know if flour has gone bad?
Worried about that bag of whole wheat flour in your pantry? The best way to tell if it went off is to sniff it. “When the flour has gone rancid” [or] oxidized, it will smell like Playdoh,” Tegetoff said. “The rancid aroma and taste will continue in the final product. It will not serve the purpose.”
There are all kinds of high-tech products that can help keep dry goods fresh for longer, such as mylar bags and oxygen absorbers. But flour doesn’t need to be vacuum sealed to stay fresh — all you need is a freezer for the flour to taste its best. Better yet, buy smaller amounts of flour if you don’t bake much.
Buy what you need, then buy more – you’ll get more space in your pantry or freezer and you’ll benefit from eating fresher flour.
Glass jars with hand turned wooden lids
Those paper bags of flour from the grocery store aren’t packaged for long-term storage — when you get home, transfer the contents to a tightly sealed container to keep bugs, moisture, and air at bay. These jars are a stylish way to store flour, sugars and other dry baking essentials. The hand-turned wooden lid twists on for an airtight seal.
OXO 8 Piece Baking Supplies POP Container Set
This eight piece set of food storage containers is perfect for storing flour, sugar and other dry goods. The lids fold up for an airtight seal and the set includes two scoops and a brown sugar saver. Plus, the containers stack neatly on top of each other to keep your pantry clean and organized.
Ultimate 7 Piece Set of Nested Storage Bins
Freezing staples in the pantry will certainly help them last longer, but not all containers do well in the freezer. Store whole wheat flour with confidence in these freezer-safe, airtight containers. This seven piece set comes in a variety of sizes and is perfect for leftovers and lunches alongside your dry goods.
Share your best storage tips in the comments below.