If raw eggs are nearing their expiry date, can they be preserved in the freezer? Would there be any issues with them after taking them out of the freezer?
Yes, but not in shell (they explode, often spectacularly).
See http://www.ochef.com/56.htm for some more information. In general, whites are better to freeze, although you can freeze yolks as well.
You have two options for freezing egg whites:
- Use an ice tray and place one egg white in each of the wells
- Gently mix the whites (don't whip) and place the mixture, either into ice trays or freezer bags.
Approximately 2 tablespoons of egg white mixture equals a single egg.
You can freeze egg yolks but you need to add something to the mix, otherwise the yolks become gelatinous and unusable. Typically adding a small amount of salt or sugar to the beaten yolks should prevent this from happening.
If you're going to use the egg yolks without freezing them you'll typically need to use them the same day. I sprinkle a little water over them before covering and putting in the fridge to help keep them from drying on top.
You can freeze them but you'll need to add corn syrup (or make a simple syrup of sugar and water) and stir it into them before freezing. You'll need to use about 1/4 teaspoon per egg yolk.
Egg yolks cannot just be frozen on their own because the water in them freezes and causes the proteins to form tight clumps. The result is that when they are thawed they have firm gelatinous texture. I've tried the salt and sugar recommendations alone and find that they don't work, probably because neither has a chance to really dissolve and act to keep the water and proteins combined.
Using the corn syrup will ensure that it is evenly blended through (provided that you stir it in well). When I make an angel food cake I will do this by adding 2 tablespoons of corn syrup to a cups worth of egg yolks (about 12). Divide it into smaller containers though as you'll just waste it if you freeze it in batches bigger than you're likely to need. 1 tablespoon of the mixture is roughly equivalent to 1 yolk. You'll of course have to use it in recipes that would be sweetened such as custards, ice cream, etc.
Eggs can't read calendars and so the expiration date is only a guide. Properly handled, they will keep just fine for several weeks or longer past their expiration date. Their quality will slowly diminish primarily due to water loss. You can judge the age of an egg by placing it uncooked in a glass of water. The larger the air cell, the more internal water has been lost, and the egg will stand more upright at the bottom of the glass. If the egg is rotten, it may float. Don't leave the egg in the water, of course.
An egg that's been around a little while (it's usually long enough by the time you buy them at the grocery store) will make peeling boiled eggs easier than if you use eggs fresh from the hen.
There may be some recipes that are more sensitive to an egg's age, but I wouldn't use frozen eggs in them anyway.
Milk, on the other hand, is quite adept at calendar reading.
Freezing raw eggs in the shell will cause them to burst the shell though.
Yes, egg whites freeze fine. There's nothing special you need to do - just put them in a freezer bag. Some people freeze them in an ice-cube tray first, for easy measuring later.
I made a perfectly good sabayon (zabaglione) with unbeaten frozen egg yolks that I hadn't mixed anything into - I just put them in a cup and into the freezer. But maybe I got lucky, as I've also read elsewhere that adding sugar or a bit of corn flour (corn starch) helps.
I saw a chef's video podcast thing where he said that egg whites should last in the fridge for many weeks. I haven't tried that myself, though.