Do you really know what freezer burn is? It's that funny discoloration on the surface of your hamburger meat, right?
Freezer burn is what occurs when foods are poorly sealed when frozen. The dry freezer air sucks the moisture from the surface of the meat—essentially freeze-drying the exposed area. The discoloration you observe is a result of the tiny cavities remaining from the "evaporated" water, thereby scattering light and causing the surface to appear white.
Freezer burned food is actually not bad for you. In fact, trim the affected area off and it'll be just fine.
Refrigeration is valuable because it prevents bacteria from devouring your food before you do. And, because all life requires liquid water to be able to function, freezing foods brings all bacterial activity to a standstill.
While frozen foods will be safe to eat for millennia—or at least until your freezer gives out—
it's quality of taste and texture that suffers over time.
First, consider what happens when something freezes. Did you ever make popcicles when you were a kid? My mom had a nifty trick. She would mix Kool-Aid and bring it to a boil just before freezing. This slowed the freezing process, producing a popcicle of icy flakes instead of a hard, jawbreaker of an ice cube. (Bless you, Mom!)
The same thing happens when you freeze a piece of meat or vegetable. The water within the individual cells of the food freezes into tiny shards of ice.
The slower the food comes to freezing, the longer the shards of ice formed. Then, as the food thaws, these shards of ice burst the cell walls, thereby releasing all the fluid.
This explains why meats can be a bloody, squishy mess when thawed and veggies look deflated and watery.
This damage can be averted in varying degrees by applying some principles of a process called "flash freezing."
One of the laws that allows flash freezing to work is that the faster water comes to a freeze, the smaller the crystals that are formed.
Let's say you have a nice beef tenderloin, but only need half of it for tonight's dinner party. These are the steps to follow to approximate flash freezing in your own freezer:
- Put the meat on a cookie sheet or a large plate for maximum exposure to air. No need to cover it just yet...
- Place the meat in the coldest part of your refrigerator—this is, believe it or not, the top of your fridge, not the bottom, because the top is where the cold air vent is—for about an hour so that it's as cold as possible without freezing.
- Transfer the plate directly into the freezer and set your timer for one hour. Still no need to cover it yet...
- After an hour (and please don't forget), gently remove the meat from the plate, wrap it nicely with plastic wrap and then seal this package in a gallon Ziploc.
- Throughout the process, do not shift the meat or poke it, so as not to cause any shards of ice to burst through the cell walls.
- When thawing, do so gently at the bottom of your fridge at least 24 hours in advance. And, of course, don't rest anything on it!
You will be amazed at how little leakage you'll have. And the quality of the flesh will be, to the average lay person, just as good as fresh!
When freezing cooked dinners, I follow a similar process. After putting the food into its container, I put a fan over it to cool it down quickly. Then I cover the dish and put it in the fridge. I'll generally let that dish sit in the fridge for several hours before freezing.
How long do meats last in the freezer?
As long as food is kept solidly frozen, it won't become unsafe to eat. However, nutrients, texture and flavor do decline. Write dates on your frozen meats and, as a general rule, throw them out after three months. Some things last longer: six months for lean pork, up to a year for lean red meats.
Freezing fruits and vegetables? That's a whole 'nother article!
Bon Appetit!