I got a lot of feedback from last week’s article on freezing foods. It seems like everyone is doing it. Did you look in your freezer after last week’s article? There are a few more things you need to know.
Freezing does not sterilize foods, it simply retards the growth of microorganisms and slows down chemical changes that affect quality or cause food spoilage. Microorganisms do not grow at 0 degrees Fahrenheit, but most are not destroyed and will multiply as quickly as ever when the frozen food is thawed and allowed to stand at room temperature.
You need to maintain a temperature of 0 degrees Fahrenheit or less to keep frozen foods at top quality. The storage life of foods is shortened as the temperature rises. If you stored something at 0 F it would last for a year, at 10 F three months, at 20 F three weeks and at 30 F five days.
If you get small ice crystals during freezing it’s OK. Fast freezing will form small ice crystals. Large ice crystals from slow freezing will rupture the cells and cause a change in the texture of your food. Ice crystals are sometimes caused by fluctuating temperatures that will result in the growth of larger ice crystals. This will damage cells and creating a mushier product. Temperature fluctuations can also cause water to migrate from the product.
Not using the right packaging material will cause your food to lose moisture, color, flavor and texture. The good ice crystals will evaporate from the surface of your food resulting in freezer burn. That part of your food will become dry, grainy and brown. Your food will also become tough. Freezer burn will not make a food unsafe but you may not like the taste.
You have to use the right packaging. The main purpose of your packaging is to keep your food from drying out and to preserve its nutritive value, flavor, texture and color. Good packaging materials should be:
- Moisture/vapor-proof or at least moisture resistant
- Made of food grade material or designed to be used for food products
- Durable and leak-proof
- Doesn’t become brittle and crack at low temperatures
- Resistant to oil, grease or water
- Protect foods from off flavors and odors
- Easy to fill and seal
- Easy to mark and store
Freeze foods as soon as they are packaged, sealed and ready to go into the freezer. Do not overload your freezer with a lot of unfrozen food. You should add only the amount that will freeze within 24 hours. That’s about two or three pounds of food per cubic foot of storage space. If you overload your freezer it will slow down the freezing rate. If your food freezes too slowly it may lose some of the quality. You should leave space between packages so air can circulate freely. You should arrange your food so you use your oldest food first.
When freezing meats or seafood its important to freeze them right away as soon as you get them home if that's your plan. You should never hold raw meat in your fridge for a number of days and then freeze it.
You should remove from your food from the Styrofoam or plastic supermarket trays. For best results divide ground meats into portions or patties before freezing. If you double-wrap it will extend shelf life and prevent freezer burn.
You should not refreeze food if it’s been defrosted above refrigerator temperature (40 F) except for very high acid foods, such as fruits. If your food shows any signs of spoilage, has an odor or is discolored you should dispose of the food without tasting. Note, you can’t rely on appearance and odor to determine if your food is good. Sometimes foods may look and smell fine, but if they’ve been at room temperature 40 F or above, food poisoning bacteria may have multiplied enough to cause illness. Meats, such as beef, pork, veal, lamb and poultry can be refrozen if it is still firm with ice crystals. Meat still safe to eat can be cooked and refrozen. Throw away any meats if they have any signs of spoilage such as an off-color or bad odor. Defrosted fruits that smell and taste good can be refrozen. Vegetables should be refrozen only if they contain plenty of ice crystals. Shellfish, prepared foods or leftovers should not be refrozen if defrosted. Never refreeze melted ice cream, cream pies, eclairs or similar foods. Unfrosted cakes, uncooked fruit pies, breads and rolls can be refrozen. You should use refrozen foods as soon as possible.
If your freezer stops working you can use dry ice to keep it cool. Twenty-five pounds of dry ice in a 10 cubic-foot freezer should hold the temperature below freezing for two to three days.
You should always thaw food in the refrigerator. This is the safest thawing method. If food is thawed outside your refrigerator microorganisms grow very fast.