Optimal egg size?

Question

Yesterday while making some pancakes I came to the realization that I may have been sabotaging recipes that call for eggs.

For years I've always purchased the largest sized eggs I can get in the grocery store. I've done this mostly with fried and scrambled eggs in mind.

When making something like pancakes, or cakes, or cookies etc... is it better to have a smaller egg?

Is there an optimal sized egg for baking?

Answer

US baking recipes are generally based on (US) large eggs. (I'm not sure about other countries.) Some recipes even explicitly say that. If you've been using (US) jumbo eggs, then you're using ~25% too much egg in your baking. The effects of that will of course vary from recipe to recipe. It's not so much that large is "optimal", but rather that it's what the recipes are calibrated to.

You'll see several standardized sizes of eggs in the store:

• Jumbo: > 2.5 oz. (71 g)
• Very Large or Extra-Large (XL) > 2.25 oz. (64 g); 56 mL (4 tbsp)
• Large (L): > 2 oz. (57 g); 46 mL (3.25 tbsp)
• Medium (M): > 1.75 oz. (50 g); 43 mL (3 tbsp)

I got this from wikipedia's article on chicken egg sizes, which also lists egg sizes in other countries, which others in other countries could compare to the US sizes!

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