Shortly after my 2004 Kenya trip, with a little bit of leftover spending money and a newfound conviction about wasting food, I purchased a FoodSaver.

This is a gadget you see advertised on infomercials on weekend television. But they also sell it at stores like Wal-Mart, Target or even Kroger. In case you’ve never watched one of the infomercials, FoodSaver is a home vacuum-packaging system. You either use pre-cut plastic bags or cut bag material from a roll to a custom size. The item you want to package is placed inside the bag, and then the open end of the bag is placed into the FoodSaver. The machine pulls all the air out of the bag and then automatically seals it shut.

Vacuum sealing simply extends the shelf life and quality of what you’re saving. If it was perishable and required refrigeration before you sealed it, it’s still perishable — and still requires refrigeration — after being vacuum-sealed. But it will last longer and taste less like leftovers. Tonight, I made lasagna, and after eating tonight’s portion I put the rest of it in the fridge to cool down. Once it was cool, I cut it into individual servings and vacuum-packed each serving in a separate bag. One bag went into the fridge for use later this weekend; the others went to the freezer.

You can also buy things like meat or cheese in larger volumes when there’s a sale (or at a warehouse club), and vacuum seal whatever you don’t plan to use right away. It’s frustrating when cheese molds in the refrigerator — but it can’t mold if it’s vacuum sealed the airborne spores can’t get to it.

When I get ready to reheat one of the portions, I can boil or microwave the food right in its plastic bag.

The bags are more expensive than zip-top bags, which you need to take into account when deciding whether or not you’re saving any money. You lose about 2″ each time you cut a bag open, but if there’s still room you can put any remaining food back into the bag and re-seal it. Or you can wash a bag and use it to seal something else — except after boiling or microwaving, in which case you’re supposed to discard the bag.

The machine also comes with a little plastic hose which can be used to remove the air from specially-made canisters. Liquids or easily-crushable items, which wouldn’t work in a plastic bag, can be vacuum-sealed in a canister — or, by use of a special jar-sealing attachment, you can even vacuum seal standard mason jars. (This is NOT a substitute for canning procedures, as they tell you repeatedly in the instructional video. Whatever you’re sealing is still perishable — provided it was perishable in the first place.) I haven’t tried sealing brown sugar yet, but they say it stays soft and spoonable when kept in a vacuum canister or vacuum-sealed mason jar.

There is actually a way you can vacuum seal liquids in a bag — by freezing them first. You can freeze a single serving of soup, chili or stew, then pop the frozen block out of its container and vacuum seal it in a bag. Pop it back into the freezer. Homemade chicken stock can be poured into ice cube trays, frozen and then vacuum packed as cubes. (Yes, I’ve actually made homemade stock and stored it this way.) When you get ready, you can use only as many cubes as you need and then reseal the rest.

A small, shallow canister can used for marinating meat. The FoodSaver people claim that marinating in a vacuum causes the marinade to be absorbed faster by the meat. I’m not sure I can tell that much of a difference, but I’m willing to take their word for it.

Black & Decker makes a vacuum-sealing unit that sells for considerably less than the FoodSaver brand, but I researched online and found some customer complaints about that unit. I went ahead and spent the extra money for the FoodSaver. In all, I have been happy with it — except for a mysterious month or two when it would only “catch” and start pulling a vacuum about once in three or four tries. Some people in an online discussion board suggested that I remove, clean and replace a foam rubber gasket in the unit, and that helped– but the machine still seemed to miss too much of the time. Then, suddenly, it started working normally again, and it has ever since. I can’t explain it; perhaps the culprit was some tiny piece of something in the machinery that worked its way loose.

I am probably not seeing the dramatic savings advertised on the infomercial, but I think I’m probably saving a little money, and I am not wasting food. And I could probably use the machine more often and aggressively than I am now doing. I would recommend looking into it.