Why do yolks break so easily (sometimes)?

Yes, the freshness is the factor. In the US eggs are sold in three grades: AA, A, and B (rare). The grading is based primarily on age. AA are the freshest, and B the oldest.

Here is a diagram depicting the internals of an egg:

The characteristics of the freshest eggs are:

• A large thick albumen (white)
• A small thin albumen
• A sturdy thick chalaze
• A small air space
• A sturdy round yolk when lying flat

As the egg ages the following things happen:

• Thick albumen breaks down, getting smaller
• Thin albumen gets larger
• Chalazae degrades getting thinner and weaker
• Air space increases
• Yolk membrane weakens, when cracked it lies flatter
• Embryo may become visible as a red speck

As a result of the weakening membrane the yolk is indeed easier to break. Michael's suggestion to use your fingers to separate the eggs is spot on. The edge of an egg shell is a little too risky for reliable separation of eggs.

Sometimes the sharp edge of the second shell can cause a break. Try using your hands instead of the shell to do the separation. Just pour the whole egg in your hand and then slowly open your fingers to let the white go through.

As others have told already, the fresher the egg, the easier to manipulate.

European regulation calls for 28 days for the 'best before' date. If they are sold within nine days after laying, they are called 'Extra'. They cannot be sold after 21 days after laying.

So, look at the date on the box and choose the freshest eggs.

The reason the egg yolks break up easily on contact with a pan or taking them out of the egg is because the hen has a lack of protein in her diet. That's it in an "eggshell". It could be low quality feed, molting or stress. I raise chickens and fresh eggs.

As stated above, your eggs should not be kept in the refrigerator. Keep them on the counter pointy end down. Cold Temps aren't good for an egg and freezing will ruin it. Eggs laid in winter pose no problem unless they aren't collected right away. Commercial eggs in the US that have been washed (they all get washed) don't fit this rule. Since the bloom has been washed away, they have to be kept in the fridge. For what it's worth, cooking with a cold egg doesn't work as well as cooking with a room temperature egg - at all.

As mentioned the freshness of an egg determines the strength of the yolk. Try buying local, as it doesn't need to travel as far to get to your grocer. Also a trick is to store your eggs pointy side down in the carton, this keeps the interior of the egg in good shape. As you see hobodave posted a diagram. Also stop storing your eggs in door of your fridge, the blast of warm air every time you open your fridge effects the eggs more than you'd assume.

Also, one thing I learned when handling food. Use your hands, just be clean about it. Don't bother with fumbling the yolk from shell to shell. The shell is hard and pointy and will easily break your yolk. I prepare french dishes often, and I know the importance of having no white in my yolk and no yolks in my whites. I simply use my hands and im able to separate the yolk and whites completely by letting the whites slip away between 2 fingers.

I have kept chickens for 30 years and sometimes have trouble with overly delicate yolks. Doesn't seem to follow a seasonal pattern. Sometimes I have blamed the age of the hen (I have had hens live for 11 years) but I'm not sure. I like the 'too much corn' theory. I like to think that my girls have a good life and don't have stress. They have a huge indoor/outdoor run, fresh spring water, a fancy 'bantam' rooster etc.. Being a hot, meditereanian climate they get a lot less greenary in the summer and more corn so maybe I'll keep a closer eye on the seasonal thing.

I've raised chickens for over 30 years, and while age can be a factor in yolks that break, there are a lot of other unknowns that can cause it. We currently have about a dozen hens out of a flock of 50 who lay eggs that might as well be scrambled inside the shell. The rest of the flock lays perfectly fine eggs. Same diet across the board, and all of these hens are under 2 years old. Summer, winter, fall, rain, shine, doesn't matter with them. Different breeds, all free range. Genetics, perhaps, but their sisters don't have the same issue. We gather eggs three times a day and the oldest eggs in our fridges are never more than 4 days old. Good thing I like my eggs over hard, busted yolks.

Here's my input: Our 6 chickens (of different breeds) appear to be healthy. We let them free range from about 2 pm til they go inside themselves. We feed them a balanced organic commercial pelletized feed along with their own forage (as stated above - free ranging). We have never had a rooster for these hens. I keep the eggs (pointy side up) on the counter - unwashed. The overly delicate yolks have been increasing lately. I haven't kept track of which eggs (only 3 out of 6 appear the same - medium brown, the others are large, small and textured, so if I pay attention, I might be able to tell if the eggs are coming from one type of chicken. Other than that, I'm voting for stress - due to the extreme heat lately (late May and especially this week (first week of June) well into the 90's (degrees).

I raise my own chickens, and the eggs are fresh. I never had this problem before, but with these chickens, the yolks are breaking -- like in a frying pan, just sitting there cooking happily, or in a bowl, after going through the shell breaking without problems. I decided that it's perhaps dependent on the chicken breed, or perhaps on chance.

i live in S. Florida, and suspected lack of protein for my weak yolks; but have to note that the girls diet has not changed, and the yolks only got weaker as the temp rose into the 90's. Since i just read "cold," let me add that heat may be a possible culprit; although "stress" might cover both? I'm being advised to limit corn in more extreme temps, trying that now.

I also raise my own chickens and have recently had troubles with the egg yolks breaking as they are gently placed in a frying pan for breakfast being prepared. Although I have not recently changed their feed I have added to their diet more corn they seem to like it and they pick it up quickly. Just trying to be a good chicken owner and give them something they like but I think the corn may be the culprit just to be sure I'm going to add some more protein to their diet and limit the corn

Well, I have been raising chickens for a year and the age of the egg doesn't mean a thing. It is now winter (5 February) and almost all egg yolks break when cracked so I'm saying the cold does it. During the summer, yolks break very seldom.

Could it be the roosters? I have had chickens for about 3years no roosters and never had any problems this year I took on 2 roosters and now I am having issues with my yolks breaking.