Foods to Stock Up on -- or Not

By Elizabeth Sheer, Cheapism.com

Huge sales on food items at the supermarket are so tempting. It's an opportunity to save lots of money and ensure plenty of cheap meals (and "pantry shopping" when you're out of money or time) for days to come. But food isn't cheap if it spoils and you have to dump it, and some foods have a shorter shelf life than you might think.

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Here's an overview of foods to stock up on, and those you should buy as needed.

Canned goods. If canned goods have a "use by" date, buy as much as you know you'll consume before the deadline, which may be a few years out. The USDA warns against exposing stored cans to extreme temperatures and says to discard them if they're bulging. Highly acidic foods, like tomatoes or pickles, spoil more quickly than low acid foods, like soup or tuna fish, because the acid eventually begins to corrode the container.

Dried foods. Cheap pantry staples, such as pasta, rice, and beans, are good foods to stock up on. Already preserved, so to speak, they'll keep for years as long as they're in a sealed container. Rice, for example, can last up to 30 years, according to Utah State University; not wild rice, though -- it isn't really rice. A sealed container keeps out moisture and bugs, both of which will seriously limit shelf life.

Baking staples. Baking staples, like flour and sugar, will keep almost indefinitely if stored in a cool dark place, away from dampness, and in an airtight container (which might preclude snazzy canisters, because if air can get in, so can bugs). Baking powder and baking soda are not foods to stock up on unless you bake daily, or, in the case of baking soda, use for other purposes (e.,g., freshening the air in the fridge, as substitute for toothpaste, to clean a comb). Although baking powder and baking soda theoretically last for years, their leavening power starts to wane after about six months. Pure vanilla is almost always expensive, but grab some if it goes on sale -- because of the alcohol content, vanilla will last practically forever.

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Oils. Oils often cost a pretty penny, so stock up on this food item when it's on special. Opt for several smaller bottles rather than one huge bottle or can because oil can go rancid after a while; an unopened bottle of olive oil keeps for up to two years after the bottling date, according to The Olive Oil Time, but for just a few months once opened. Oils should be kept in a cool dark place and away from the stove. The refrigerator is optimal, which may turn the product cloudy but won't affect the taste.

Nuts. Nuts are an excellent source of protein for snacking and cooking, and a good food to stock up on when the price is right. Nuts contain a lot of oil, and like oil, can turn rancid. The life expectancy of nuts stored in the pantry is just a few weeks, but they'll last up to a year in the freezer. Commercial peanut butter contains preservatives and will last longer in the pantry than nuts -- up to a year for an unopened jar and a few months after opening.

Condiments. Mustard, horseradish, ketchup, and the like are foods to stock up on because they frequently go on sale and stay fresh for about six months once opened, according to a chart posted by MIT. Salad dressing should be used up more quickly, but unopened bottles will keep for quite awhile, so buy several if you have storage to spare. Another everyday food to stock up on is salt, which will last longer than you do. Pepper holds its potency for a few years as long as the seeds remain whole. Keep both salt and pepper away from dampness. Other spices, such as whole cloves and nutmeg, and cinnamon sticks, will retain their flavor for a long time but are rarely on sale.

Herbs. Herbs perk up the flavor of any dish, so when you find those giant containers for mere pennies, they surely seem like a good food to stock up on. But stifle the urge. Dried leafy herbs, such as oregano or thyme, should stay potent for up to three years if kept whole but only about six months if ground or powdered, says Emerils.com. As with most food items you stock up on, keep dried herbs far from light, heat, and damp, but never in the fridge.

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Vegetables. Except for onions, garlic, and potatoes, which all keep for a few weeks in a cool, dry place, only buy fresh vegetables you plan to use in the very near term. Frozen vegetables are another story -- when a sale hits, fill your shopping basket. Frozen veggies will keep for up to a year if the package is unopened and the freezer is really cold.

Meat and fish. If your freezer is large enough, meat and fish are ideal foods to stock up on when prices drop. Buy what you'll need for the next few months, but note that cut-up chicken has a shorter freezer life than whole chicken. The USDA suggests using the freezer as short-term storage if the internal temperature is higher than 0 degrees Fahrenheit.

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