Checking Eggs Before Use

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In the past, most eggs came from fertile hens, whose increased hormone levels stimulated more egg production. Of course, fertilized eggs will also, in the right conditions, grow into chickens. In modern commercial egg operations, this hormone enhancement is achieved (and controlled), by artificial means through the feed and the eggs themselves are not fertile; they will never develop into chickens. While in the past, every bloodspot might have signified the beginning of a new embryo (safek sheretz ha’of), today’s commercial methods virtually insure that this is not the case.

It is in light of this modern reality that Harav Moshe Feinstein, zt”l, (Igros Moshe, Yoreh Deah 1:36), clarifies that blood spots found in commercially produced eggs do not present any fundamental kosher problem. With respect to fetile eggs in the past where a significant doubt existed that the blood might represent a new embryo, it was necessary to throw out the entire egg if it had a bloodspot. This is also the reason why a minimum of three eggs were boiled at one time – if one of them had a spot, it would be batel b’rov to the other two. Today, however, the only concerns are maris ayin or dam beitzim (a small amount of blood from a broken blood vessel in the hen, which is not forbidden). As a result, the entire egg is never assur and mei’ikar hadin removal of the blood spot would suffice. Moreover, since the issur is not intrinsic to the egg, there is no problem with cooking a single egg in a pot. Rav Moshe, however, writes that it is a proper practice to dispose of the entire egg even today, as eggs are not expensive and a person does not incur any significant loss. Therefore, the requirement to check each egg remains in effect, as does the requirement to dispose of eggs containing actual blood spots. Nevertheless, in cases of doubt, difficulty or error, eggs are kosher, even if checking was not properly done; moreover, if blood spots are discovered during or after cooking, there is no problem with the utensils with which they were prepared.

Note: Fertilized eggs are available in the marketplace and are sold at a premium. When purchasing organic or natural eggs, a consumer should be careful to check the carton and/or contact the egg producer. Consumers wishing to consume fertile eggs should consult a competent Posek for guidelines. Some kashrus agencies will not certify eggs that are intentionally produced as they were in the past, because of the halachic complexities pertaining to those eggs.

When is Checking Required?

The accepted practice is to check each individual egg prior to use.

If one is in doubt whether the eggs have been checked, it is permitted to eat them

Blemishes Found in Eggs – What am I Seeing?

Commercial eggs undergo a screening process called ‘candling,’ which identifies eggs that are blemished. Despite candling, a small percentage of eggs found on store shelves still have various blemishes. This is especially pronounced in eggs with colored shells (such as brown eggs). Some definitions:

Protein Spots: By far the most common blemishes found, these are formed by a microscopic “seed” of foreign matter that enters the egg during the early stages of development. Though found in both brown and white eggs, they are more prevalent in brown.

Whether in the white or yolk, these blemishes present no halachic concerns and the eggs may be consumed without further action.

Greening: When eggs are boiled for too long, the yolks will often turn green. This is not an indication of any issue and may be ignored.

The vast majority of commercially available eggs are not fertile. While it cannot be guaranteed that no eggs are fertilized, the incidence is so small as to be halachically insignificant. Therefore, while, as a matter of practice, we are careful not to eat eggs with blood spots, no fundamental issur is associated with any blood that might be found in commercial eggs [unless specifically sold as “fertilized”]. Moreover, most spots found in eggs are not blood spots and present no halachic problem whatsoever.

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The words of this author reflect his/her own opinions and do not necessarily represent the official position of the Orthodox Union.