Eggs. It’s hard to avoid ’em – they make an appearance in practically every cuisine, in one form or another. From breakfasts to dinners to snacks to desserts, eggs have firmly entrenched themselves in our collective culinary psyche.
In recent years, they have been banished to the culinary doghouse for their high cholesterol and fat content. However, nutritionists acknowledge that eggs are an important source of protein, essential vitamins and minerals and can make a significant contribution to a healthy diet. After wading through many terabytes of conflicting points of view, I found this little extract from the Harvard Heart Letter (a Harvard Med School newsletter). I think it’s a sensible, easy-to-understand, and succinct overview from a reliable, agnostic source. I also found a new study pointing to the health benefits of eggs, including – incredibly – an indirect but significant contribution to weight loss.
And now that that’s out of the way…
Contrary to popular belief, the color of an egg’s shell has nothing to do with how an egg will taste (affected mainly by a chicken’s diet), or with its nutritive value (indicated by yolk color). The color of the shell is dictated solely by the breed of hen, and unless you want to use eggs as a table centerpiece and need to color coordinate them with your napkins,their color shouldn’t influence your buying decision at all.
How Fresh Is That Egg?
There’s something else you should know about the shell, however. It’s porous. What does this mean? Well, for one thing, it allows an egg to absorb strong odors. Never store cut onions or garlic near your eggs – unless, of course, you want them to taste of onion and garlic. If you can, store them in cardboard egg trays that insulate them from other odors in your fridge while retarding moisture loss.
Porosity of the shell is also a major factor in contributing to eggs going stale. When buying white eggs, hold them up to the light. You should be able to see an air pocket at one end (usually the rounded end). When the egg is laid, this is really tiny, but as it matures, the porous shell allows more and more air into the egg, causing the air pocket to expand as the egg loses moisture. Ergo: the smaller the air pocket, the fresher the egg. This also explains why our grandmothers used to test eggs for freshness by dunking them in a bowl of water. The older eggs would float (because of the air), while the fresh ones would sink. To add nuance to that test though:
- If an egg sinks and lies horizontally – it’s so fresh that the hen that laid it is probably still clucking indignantly nearby.
- If it sinks, but lies at an angle, it’s about a week old.
- If it sinks, but stands upright, it’s probably ten days old, verging on stale.
- If it floats, it’s as old as the biriyani that’s turned into a science project on the bottom shelf of your fridge. Toss the egg and the biriyani out, dude.
When To Use A Day-Old Egg
Are fresh eggs always desirable? Well, no. Depends how you want to cook them. A too-small air pocket makes it difficult to peel a hard boiled egg, so you probably want an older egg for that. If you like your eggs poached, or fried sunny side up, though, the yolk of an older egg will have lost moisture and become flat instead of plump… so choose a fresh egg. Scrambled eggs and omelets – the age of the eggs doesn’t really matter, as long as they aren’t rotten. A good way to use up older eggs.
Which brings us to storage. Storing eggs with their pointed ends downwards helps keep the yolk centered. And unless you’re going to use them real quick, the door is not the best place to store eggs – the temperature fluctuates each time you open and close the fridge.
Unbroken eggs will usually keep in the fridge for up to a month, depending on how fresh they are when you buy them. Once out of the shell, egg yolks will keep for a couple of days in the fridge, if submerged in room temperature water and then covered in clingfilm or an airtight container. Egg whites will keep for up to four days in the fridge; they need to be tightly covered, but you don’t need to submerge them in water. You can refrigerate hard-boiled eggs will keep for up to a week.
Can you freeze eggs? Sure, but not in their shells. To freeze whole eggs or egg whites, beat until well-blended, place in an airtight container, and freeze. Do the same for egg yolks, but be sure to add either a pinch of salt (for savory dishes) or sugar (for sweet dishes) to prevent them from thickening over time. To defrost, place in the fridge overnight – never defrost at room temperature. Be sure to use defrosted eggs immediately. Do not refreeze.