There are a lot of mysteries surrounding baking that often cause people to become discouraged or, at best, a little confused. Do you really need to use cake flour if a recipe calls for it? Does that butter actually have to be at room temperature? A question I hear often concerns egg size in recipes.
When buying eggs at the grocery store recently, I even noticed the egg cartons themselves saying "equivalant to an extra-large egg" or "equal to a jumbo egg." So the topic is obviously on shopper's minds. And rightfully so.
Following a recipe's instructions regarding egg size could make the difference between a perfect cake and a cake that's a little too dry (or wet). Eggs add moisture to batters and mixtures, and when it comes right down to it, baking is pretty darn scientific. If you mess around with the flour/moisture ratio, your end product isn't going to turn out the way the recipe writer intended (and you'd hoped for).
A good rule of thumb: even though it seems like a small consideration, listen to what egg size the recipe calls for. An oversight here could amount to a difference in 2 or 3 tablespoons of moisture in your batter: enough to throw off a recipe. But let's get real for a moment: you also can't be buying cartons of various-sized eggs and, even more, many of your recipes won't even indicate an egg size. So what to do? Most U.S. recipes assume you'll use a large egg unless otherwise indicated. So this is often a safe bet. Stock up. Now let's get baking.
Related: Basic Techniques: How to Fry and Egg
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actually, if you buy pastured eggs from a local farm there is a huge variance in egg size.
I have been buying local, pastured eggs for a few months and while in general they seem to have only slight variations in each carton (generally ranging from large to xl), this week my carton had two eggs in it that were smaller than *any* chicken egg I have ever seen, even smaller than medium eggs I bought by accident once. I used them for breakfast so the size didn't really matter, but I knew when I opened the carton that I didn't want to try to bake with them. So it is possible to wind up with a mixed carton in some situations!
I have noticed that the "large" eggs that you buy at the grocery don't seem as large as they used to (I've been baking for a long time)-in fact they seem much smaller.
I don't think I've ever seen a recipe specify what size eggs should be used, but if it did specify, I would certainly follow the instructions. If it's important enough that an recipe be specific down to the egg size, then I'd do what it says.
So, a more important question to me is, what size should you use when it just says "eggs"?
I've had that problem, the eggs I buy from our greengrocer are XXL, weigh more than 70g, and the weight most recipes call for is 65g (size L, I think), so if there are many eggs in the recipe I sometimes use one less to get the amount right.
We keep chickens and, as FancyD says, there is a huge variance in size. A couple times I've failed to pay attention and ended up using the really huge ones for baking (beyond jumbo), and had to increase the baking time by about 20 minutes. Now I'm really careful. Also, @Ranyart, you're lucky the small eggs had yolks. We've had a couple tiny yolk-less ones.
All of Ina Garten's recipes call for extra large eggs and I don't buy them. Consequently, I don't use any of her recipes. I think for a major cookbook author to use a size egg that the mainstream cook doesn't even have access to let alone buy is very out of touch with the world. But then, I think she is out of touch anyway so it really doesn't matter.
One way I deal with varying egg sizes is to just use a scale. Well generally I find using a scale just makes things that much easier and the results are more predictable and repeatable....so if a recipe calls for extra large eggs and I only have large or medium (or buy from the farmer's market), I just use as many eggs as required to get close to the right weight. If you want to be as precise as possible and need to add less less than a whole egg to reach the correct weight, just lightly scramble the egg first and measure it out like any other ingredient.
In contrast to CCP MBD's experience, I've made Ina's recipes with regular (large) eggs and had them turn out just fine. And yes, you can argue that Ina is a bit out of touch but her recipes are some of my most favorite, most consistent and most successful. Anyway. :)
I've been buying eggs from a friend's dad's chickens and cannot get ENOUGH. I love the variation in shell colors. Plus the very first egg of his I ever ate had two yolks when I cracked it, which can only be good luck.
I don't know for everyone else, but in Quebec eggs come *at least* in medium, large and extra large size at the grocers. some places also have small and jumbo eggs. And their size/weight is dictated by some laws so you can' t pass med eggs for large ones.
I've heard that laying extra large eggs causes pain and stress to hens. Apparently, larger egg size can be produced through selective breeding and a high protein diet.
There is a difference in size, if you use eggs that are too small, then your batter will have less liquid and your product will be dry, among other problems.
This is an example of why it is best to use a scale in the kitchen. If a recipe calls for 3 ounces of eggs, or 155 grams, then you're more concerned about how much egg you need, and not how many of what size.
I just found something from culinary school concerning eggs. Per dozen, large eggs weigh 24 oz, medium, 21 oz, extra large 27 oz. I hope this helps!
Eggs are "sized" according to weight (mass) and not actual physical volume of the egg itself, due to the presence of air pockets between the shell and the Good Stuff™