San Jose Mercury News article: The basics of freezing

Posted on February 5, 2009. Filed under: Cooking and Eating, Home & Garden, Uncategorized | Tags: food, frugal living, Living Well on a Budget, money saving tips |

The basics of freezing

Mercury News staff and wire reports
Posted: 02/03/2009 05:00:00 PM PST

Nothing ever rots. That’s the good and bad of the freezer. Good because its preservative powers let you stock up on bargain meat, save perishable ingredients, revisit your summer garden in February. Bad because, without the motivation of stink, it can become a bleak tundra of mysterious packages, their contents iced and freezer-burned beyond redemption.

To bring your freezer back from the dark side, some tips and inspiration:

The first rule of freezing

Do it fast. Slow freezing allows the formation of large ice crystals that will damage food’s cell structure. The two main components of quick freezing:

Cold. Keep your freezer at 0 degrees. If your refrigerator’s freezer gets opened a lot, consider using a stand-alone freezer for long-term storage.

Shallow.  Food to be frozen should be no more than two inches deep, so look for flat-storage options, such as shallow containers and bags laid flat. Don’t stack packages to be frozen.

The second rule of freezing

Reduce the amount of air around the food, by vacuum-sealing or storing in a tightly sealed container or bag. (Containers need an inch of head space to allow for expansion.)

The third rule of freezing

Label and date.  How long will it be good?

Safety: Food is preserved indefinitely at 0 degrees, though it needs to be handled properly before and after freezing. Bacteria or mold can become active again when thawed.

Freshness: The U.S. Department of Agriculture’s maximum recommended storage times for quality range from a month (sausage) to a year (uncooked beef roasts). The main enemies are ice crystals and freezer burn.

Freezer burn — dryness caused by air — isn’t unsafe; just cut away the damaged spots.

Defrosting
The easy way is in the refrigerator, where food won’t get warm enough for bacterial growth. Next best are immersion in cold water (in a leakproof plastic bag) or, if you plan to cook immediately after thawing, in the microwave. The USDA warns against defrosting in your car, dishwasher or yard. Refreezing It’s OK to refreeze raw food that has been thawed in the refrigerator (though the texture may suffer). It’s OK to refreeze partly frozen food as long as it hasn’t been warmer than 40 degrees for more than two hours.

Containers
Food will be a lot better protected by containers intended for the freezer than by your old yogurt containers. A test of various methods by The Washington Post food staff yielded some general rules:

Plastic wrap and food storage bags tend to become less airtight over time. Even the heavier bags intended for freezing shouldn’t be trusted much past a month. For best results, use two layers, wrapping food in plastic wrap, then sealing it in a freezer bag. If microwaving to thaw, remember to vent bag at least an inch and watch that it doesn’t melt. Home vacuum-seal methods, like Food Saver, sometimes require multiple tries to get an airtight seal; most problematic are meats or items containing moisture. Recheck the seal after a month in the freezer.

Polypropylene freezer containers, of flexible plastic, are available in a range of prices, from supermarket products to more expensive models with easy clip or snap fasteners. The inexpensive ones are prone to lose their tight seal after a month in the freezer. And read the labels: Some are not made for microwave and dishwasher, and some should not be used for fats or oils. Polycarbonate freezer containers, of rigid, clear plastic, are good options for long-term freezing and for microwaving — though you’ll pay more. Brands include Freshvac and Snapware.

Eggs
Don’t freeze eggs in the shell. Egg whites can be frozen easily; some people freeze them in ice cube trays, then store in plastic bags. Yolks are more problematic, because they get gummy. The solution: Beat a quarter-cup of yolks with 1½ teaspoons of sugar or 1/8 teaspoon of salt, then freeze for up to three months. Then remember to use appropriately, sweet or savory.

Meat and poultry
They can be frozen in supermarket wrapping for a month or so; any longer than that, and you’ll want to give it more solid packaging. Meat vacuum-packed by the manufacturer generally doesn’t need more protection.

Produce
Most vegetables should be blanched before freezing — cooked in boiling water for two or three minutes — to halt enzyme activity that can diminish flavor and color. Most fruits benefit from freezing in syrup or with a sprinkling of sugar; some also need citric acid or ascorbic acid to prevent discoloration. Bags of purchased frozen fruits and vegetables should be double-packaged inside a freezer bag to prevent ice crystals and extend shelf life.

Sources:
Washington Post, U.S. Department of Agriculture Resources General freezing guidelines: www.fsis.usda.gov/FactSheets
Freezing produce: www.extension.umn.edu/living; click on “food preservation” in the left column

Products:
Among retailers of freezer containers are the Container Store and Bed, Bath and Beyond.

What’s in your freezer? Some of my freezer staples include:

Homemade Stock

Tomato sauce

Butter

Bacon

Grey Goose Vodka

Parmesan rinds

Ginger root

Cookie dough

Frozen bags of organic fruit (for yogurt smoothies)