>> Update on 3/30/11: Thanks again to all those who provided great feedback. An updated version of the infographic had been added below and you can read more about it here. The infographic is also available for print here.
When I got a question asking about the different labels on eggs and shortly thereafter had a brunch-time discussion about how to order eggs, I realized that it was time for another Culinaut infographic (check out the previous one on the dangers of cooking with teflon).
So here's my attempt at capturing egg basics in an infographic guide. For simplicity, I stuck to chicken eggs in their most common forms. The top of the graphic covers info relevant to buying eggs from a store, and the bottom has some of the basic egg cooking/ordering options. It's also worth noting that the sizes, grades, and farming methods here are based on US guidelines and differ in other countries.
Updated version of infographic based on reader feedback (read more about it here):
larger viewing options on flickr)
Beyond the Basics
Over the course of researching data for this guide, I came across tons of great information. Some of it was just fun trivia, there were some great tips on how to cook a better egg, and some really made me take a hard look at the ethics in eating. Unfortunately, a lot of those details didn't make it into the infographic, so here are some that you might find interesting:
- Brown, white, and blue?
Brown and white eggs are pretty common, but did you know that there is a type of chicken, the Araucana, that lays blue eggs?
- Expert approaches to cooking eggs
Ever wonder why hard boiled eggs can get that unsightly (but harmless) gray-green ring around the yolk? It's actually the result of a chemical reaction between the sulfur in the white and the iron in the yolk. Longer cooking and high temperatures tend to produce more of the sulfide. Jacques Pepin shows how he hard boils eggs in here on his More Fast Food My Way series, all of which can be found on YouTube. This includes some clever tricks like making a pinhole in the shell before cooking to release pressure, and leaving eggs in cold water for longer so that the sulfur dissipates and you hopefully get a less stinky egg and no green ring.
For a more meticulous and scientific approach, Serious Eats's J. Kenji Lopez-Alt has a great guide to perfect boiled eggs as well as a clever egg taste test that explores the different types of eggs. Similarly, Cooking for Geeksdescribes various methods for cooking an egg and the effects on the egg protein as you progress along the temperature scale. And for a thorough understanding of eggs, look no further than Harold McGee's classic On Food and Cooking,which devotes all of Chapter 2 to the history, biology, chemistry, and cooking of eggs.
- Egg safety
Eggs should always be stored in the refrigerator. To prevent food poisoning from bacteria like salmonella, On Food and Cookingrecommends that you keep an egg at 140F/60C for 5 minutes (maintains a runny yolk), or 160F/70C for 1 minute (hard yolk). An alternative is to use pasteurized eggs.
Farming practices are probably the most confusing area regarding eggs (at least that's how I felt) due to the complexities and ambiguities in US egg farming standards. There are always exceptions, but generally speaking, it seems that egg cartons that aren't labeled with a specific farming method were probably factory farmed. This still seems to be the most common farming method for eggs and raises the most health and ethical questions, as systems such as battery cages (photos not for the faint of heart) are often used.
It turns out that there aren't really any regulations in the US around labeling an egg as "cage-free" or "free-range". Thus, you hear the stories of Omnivore's Dilemmafame, where eggs are labeled as free-range even though the chickens only had access to a tiny outdoor patch. If you're looking for the most humane eggs, the Humane Society has a helpful and more comprehensive guide to egg farming methods.
There are plenty of other ways to cook an egg which I didn't get into this time around, like omlettes, quiches, tea-eggs, or pickled eggs just to name a few. We'll have to save those for a future post. Til then, have an eggsellent time cooking! (couldn't resist just one egg pun …)
On Food and Cooking by Harold McGee
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