These foods can stay fresher for longer or even taste better if they're kept in the refrigerator. Odds are, however, they're in your pantry right now.

A refrigerator keeps foods fresher longer and helps preserve taste so you get the best flavor out of each ingredient. You probably think you know what belongs in the fridge and what doesn't, but you may be surprised by the common ingredients that you store in the pantry that actually should go in the fridge. These five foods should be refrigerated but are likely in your pantry right now. So, make some space between the bread and honey (two foods that don't have to be refrigerated), and we'll explain why.

1. Natural Peanut Butter

Peanut Butter Balls

Natural peanut butter is peanut butter in its purest form. In most cases it's solely ground-up peanuts and maybe a dash of salt. Because of its unrefined state, natural peanut butter acts a little differently from commercial peanut butter. In natural peanut butter, the oils from the peanuts can separate from the solids, something that doesn't happen with "regular" peanut butter, thanks to the addition of hydrogenated oils or palm oil.

If you don't plan on finishing your jar of natural peanut butter within a month or so, or if you live in a hot climate, consider refrigerating it. The oils in the peanuts can go rancid if it's not kept cool.

Likewise, if the label recommends refrigerating after opening, follow the instructions. (Also, if your peanut butter develops mold, toss it. Because natural peanut butter is processed without preservatives, it's at high risk for mold, according to the Department of Agriculture.)

If you're concerned about spreadability because your peanut butter is hard from being in the cold refrigerator, scoop out what you need and let it warm to room temperature or pop it in the microwave for a few seconds before spreading.

2. Whole-Wheat Flour

Sticking flour in the fridge may seem like a late-night blunder, but if we're talking whole-wheat flour, it may not be a bad idea. The wheat germ in whole-wheat flour can go rancid quickly. Once opened, store your whole-wheat flour in the refrigerator or freezer for long-term use.

A word of caution: Whole-wheat flour has the tendency to pick up unwelcome flavors, so store it in a plastic bag or airtight container, and avoid storing it next to anything with a strong odor, such as fresh onions or garlic.

3. Nuts

Apple-Cinnamon Overnight Oats

Nuts are a great healthy snack option. Buy them in bulk and store them in your fridge (or freezer, if you want them to last even longer).

The oils in nuts turn sour when exposed to heat, so unless you'll be eating them up within a month or so, they'll need to stay cool. The freezer is a great option: since nuts have very little water content, they never freeze rock solid and will last almost indefinitely stored there.

4. Oils

Greek Salad Dressing

Pictured recipe: Greek Salad Dressing

If you use up your cooking oils quickly, you may not have to store them in the fridge. But if you buy oil in bulk or you have a few bottles, you may want to consider refrigeration.

Most oils are fine unrefrigerated, if you use them up within a month or two. But keep in mind that light, air and heat can cause oils to spoil more quickly than if they weren't exposed to those environmental factors. Heat is especially problematic since cooks tend to store oil next to their stoves, where it's easy to reach when cooking. Keeping certain oils in your fridge may cause a harmless "cloudy" appearance and/or cause them to thicken, but bringing them to room temp will easily solve that problem.

5. Butter

Corn on the Cob with Cilantro-Lime Butter

Chances are you know someone who keeps butter out of the fridge to enhance its spreadability. That's fine, at least for a few days, but the safest place to store butter is the fridge (or freezer for long-term storage). If your refrigerator has that little compartment for butter, use it. Since butter can easily absorb odors and flavors from the items stored around it, the butter compartment will keep your butter tasting and smelling like butter and nothing else. Keep it tightly wrapped in there and in the original wrapping, if possible.

Bottom Line

Natural peanut butter, whole-wheat flour, nuts, oils and butter are better off stored in the fridge, especially if they'll be hanging out in your kitchen for more than a week or two. Make sure to wrap or bag these items, when applicable, before storing in the fridge to prevent flavor loss or change. And remember, plan ahead and temper your refrigerated peanut butter or butter before using, if you want them to spread easily.