In an era that has perfected cryogenics, you'd think that freezing a loaf of banana bread would be easy. But all too often food comes out of the freezer trapped in a block of ice. And when it thaws, it feels soggy or tastes like the spaghetti sauce you defrosted last week.

HOW TO FREEZE

Proper wrapping, sealing, and labeling will ensure your food retains its quality and texture after freezing and that you'll use it before the flavor wanes.

Store foods in materials designed and designated for freezer storage, such as sturdy plastic containers, sealed plastic bags, and heavy-duty plastic wrap. (Regular plastic wrap is too thin to protect foods in the freezer.)

Make sure the seal on the wrap or container is airtight (to stave off freezer burn) and moisture-proof (to defy ice crystals).

For easier identification down the road, label and date foods before you freeze them. Better yet, record a "good until" expiration date on the label rather than the date when you froze the food.

FREEZING POINTS

The fresher food is when you freeze it, the better it will taste when you defrost, heat, and eat it. Freezing preserves freshness, which means a just-baked bagel will be almost as fluffy after three months in hibernation.

The faster food freezes, the better its quality will be preserved. Freeze portions in small containers, let the cold air circulate evenly around them, then stack them to save space.

The less air that's trapped in the package, the better. "During freezing, air can react with fat and cause off odors and flavors to develop," says Michael Doyle, director of the Center for Food Safety at the University of Georgia. Use containers that match the size of the food you're freezing, and squeeze out the excess air in bags before sealing. Home vacuum-packaging systems (like the FoodSaver by Tilia, www.foodsaver.com) are significantly more expensive than a box of freezer bags — about $130 versus about $3 — but "if you're planning on freezing foods long-term, vacuum packaging will be more effective," says Doyle.

Food keeps best if your freezer is set at 0 degrees Fahrenheit or below. Food may not spoil if kept above 0, but its quality and nutrient content will suffer. In general, if a freezer can't keep ice cream brick-hard, then it's not cold enough. Use a refrigerator-freezer thermometer (available for about $10 at hardware stores) to check the temperature if it seems too warm. There may be a problem with overcrowding, with the seal, or with the freezer itself (which means calling a repairman).