Few things feel as frugal as tucking leftovers into the freezer.  Who among us isn’t looking to stretch food dollars or count on a meal all ready to go, needing just a quick reheating?

But, even with the best of intentions, we often lose our way when navigating the frozen terrain behind the freezer door. What are those unrecognizable solid things in plastic bags? How long have they been in there?  Are they safe to eat?

Like any tool designed to make your life easier, your freezer can save you time and money, but you have to know how to use it.  Here are some guidelines to help you develop a warmer relationship:

Seal all food before freezing it. Dehydration, or freezer burn, attacks the color, flavor, and texture of food that is exposed to air as it freezes. Use containers, bags, and paper designated specifically for freezing when storing leftovers.   (Regular weight aluminum foil, waxed paper, and thin plastic bags won’t do the job.)  Store liquids and soups in rigid, stackable plastic containers with airtight lids, and fill them to within an inch of the top of allow room for expansion. When using plastic freezer bags, squeeze out as much air as possible before sealing.

Rewap bulk quantities. When you want to keep meat, poultry, or seafood for more than two weeks, remove items from their store packages as soon as you get them home, and wrap them in freezer paper or heavy-duty aluminum foil, seal with freezer tape, and wrap in freezer-weight plastic bags.

Label everything. No exceptions. Use an indelible marker and a strip of freezer tape to label each package with the name of the item and the date you are freezing it. And when you go looking for something to eat, use the oldest items first.

Create a system. Put unfrozen meats, vegetables, and fruits in a single layer on the freezer shelf as close to the freezing plates or coils as possible.  Leave room for air to circulate around the food, which will bring its temperature down quickly and help preserve its texture and taste.  Once it is frozen, layer or stack your packages and free up the shelf for new arrivals. Did you know that when your freezer is 75 to 85 percent full, it runs more efficiently than when it harbors just a tray or two of ice and a package of frozen peas?

Check the temperature.  Invest in a freezer thermometer, widely available for $10 or less. Your freezer should be at 0° F or below. If it gets up to 10° or above your food will be only partially frozen.

Don’t re-freeze! Freezing buys you time, preserving foods that would otherwise spoil. As soon as you thaw them, the clock starts ticking.  We checked in with several food pros on this topic.  Here’s what they told us:

“I don’t generally re-freeze — with the exception of soups.” – Melissa Clark, food columnist for the New York Times and cookbook author

 “I think that the whole thing about re-freezing is that you never remember how long you defrosted it for the first time and then you add those additional days and it goes way beyond what is safe and fresh.  I don’t usually re-freeze.” – Joan Weir, chef, restaurateur and cookbook author

“I believe this is mostly a quality issue; although if you do not handle an item with good food safety technique, it can pose safety concerns.  When you thaw and refreeze foods, you damage their cell structure, which can contribute to poor texture and taste.” – Sharon Palmer, The Plant-Powered Dietitian

Wondering how long something can keep in your freezer? Check out this helpful table.