Checking Eggs for Blood Spots

What is the issue with checking eggs for blood spots? If I buy a package of eggs which is certified kosher, is this necessary?

The Aish Rabbi Replies:

When eggs are certified kosher, it means the eggs come from a kosher species. (The byproducts of kosher animals – such as their eggs and milk – are kosher, while those coming from non-kosher species are not kosher.)

In the olden days, if an egg had blood it in, it might have been a sign of fertilization. And a chick embryo, together with its entire egg, is not kosher and must be discarded.

This was also the basis for the old practice to cook only three whole eggs together. In case one of the eggs has an embryo, it would be outnumbered by the two other eggs and nullified. (It itself would have to be thrown out, but the other two eggs would be kosher.)

Today hens are raised in an environment where fertilization is impossible. (They are fed hormones to stimulate regular egg production without fertilization.) Thus, it is very uncommon to find blood spots in commercially-produced eggs. In addition, at least in the United States, eggs are further checked for blood or other blemishes using bright lights (in a process called “candling”) – although of course, an occasional defective egg will pass through inspection.

When blood is found today, it typically comes from bleeding from the hen at the time the egg developed. Such blood may not be eaten but unlike an embryo, it does not forbid the entire egg. Thus, by the letter of the law, it is sufficient to check eggs for blood spots and only remove any blood found in them, but not to discard the entire egg. The common custom, however, is to throw out the entire egg even today.

Even in earlier times, there was room for leniency in cases of doubt, such as eating unchecked roasted eggs – relying on the assumption that most eggs do not contain blood. (Some recommend checking hard-boiled eggs after the fact by examining the yoke for very dark spots.) Today, there is even more room for leniency – such as when checking is very difficult or impractical. Likewise, eggs are permitted after the fact if checking was not done. Also, if an egg with a blood spot was cooked in a pot, the pot does not become non-kosher. Finally, most people are lenient today to cook even less than three eggs together.

Note that people who eat organic eggs must be more vigilant about checking them for blood – although as above, they may hard-boil them assuming they do not contain blood.

(Sources: Talmud Hullin 64b, Shulchan Aruch Y.D. 66, Gra 12, Igrot Moshe Y.D. I:36, Yechaveh Da’at 3:57.)

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