Eggs and Blood Spots

Although most people throw away eggs which are found to contain a blood spot, as we will see, doing so may actually be quite unnecessary. The practice of checking eggs before using them goes back to the days when commercial eggs were the products of fertilized hens. Today, eggs are no longer produced in this manner. The vast majority of eggs which are found in supermarkets today are the product of hormonal and artificial stimulation and not a result of the natural reproductive process of chickens. Manipulating chickens in this way can generate a new egg every single day, making the process extremely profitable.

These mass produced eggs, often referred to as "commercial eggs" or "battery eggs", will never develop into chickens. As such, the "blood spots" found in these eggs are not truly blood. The only eggs which are produced by natural fertilization today are clearly marked as "natural" or "organic" on the package and are significantly more expensive. When one finds blood in naturally fertilized eggs, the blood is not kosher and the egg must be discarded.  The reason for this is due to the concern that the blood might actually be the early stages of an embryo.[1]

When blood is found in a naturally-produced egg, there is a difference of opinion whether or not it renders the egg non-kosher. According to some authorities, an egg is only forbidden when blood is found in the yolk of the egg. According to others, an egg is forbidden when blood is found in the white part of the egg. In order to comply with both views, one who finds blood anywhere in a naturally-produced egg is required to discard it.[2]

Nevertheless, most authorities insist that even battery eggs should be inspected for blood spots. In the event that blood is found, however, one need only discard the actual bloodspot, while the rest of the egg may be used.[3] Although some authorities recommend discarding the entire egg,[4] it is unnecessary if doing so would present a significant financial loss.[5] One who borrows eggs from a friend or neighbor which are discovered to have blood spots is only required to return the number of eggs which were found to be kosher and usable.[6]

It would be remiss not to mention that there a number of authorities who rule that one is not required to check battery eggs for blood at all. In fact, according to this approach, a battery egg may be consumed in its entirety, along with the blood spot.[7] Most other authorities, however, rule that one is required to discard the blood found in battery eggs according to rabbinical law even though it should essentially be permitted from the Torah perspective.[8] The most efficient method to check an egg for blood is to crack it into a glass. Doing so allows one to easily examine the egg from all sides.

Although examining battery eggs for blood may not be truly halachically required, it is argued that the original custom of checking eggs should be preserved. That being said, if for whatever reason a battery egg was used without having been checked, the food may nevertheless be eaten.[9] So too, any foods which came into contact with a battery egg which was not checked may be eaten, as well.[10]

Some individuals have the custom to set aside a pot exclusively for boiling eggs, in order to distance themselves from any possible kashrut concerns related to blood found in eggs. Others make sure to always cook at least three eggs at a time. This latter custom ensures that in the event that an egg was found to contain blood, it would have no effect on the kosher status of the other eggs. This is due to a concept in halacha known as "batel b'rov", which teaches that one non-kosher item is often nullified by the kosher majority, rendering even the questionable item kosher.[11]

It is permitted to forgo checking battery eggs if doing so would impose significant inconvenience or difficulty. For instance, a chef who is preparing an egg-based dish for hundreds of people need not check every egg. In such a situation one may rely on the halachic principle of "chazaka" that most eggs do not contain blood spots.[12] One may also purchase frozen or powdered eggs even if they were likely not examined for blood spots.[13] An egg which was used in a food item and was later found to have contained blood has no effect on the kosher status of the food.[14] So too, the kosher status of one's utensils are unaffected if they were used with eggs which were found to contain blood spots.[15]

[1] Chullin 64b

[2] Rema Y.D. 66:2, Aruch Hashulchan Y.D. 66:15-16

[3] Y.D. 66:7, Igrot Moshe Y.D. 1:36, Kitzur Shulchan Aruch Mekor Chaim 262:40

[4] Teshuvot V'hanhagot 1:821, 2:384

[5] Igrot Moshe Y.D. 1:36, Yechave Daat 3:57

[6] Shevet Halevi 10:133

[7] Shach Y.D. 66:12,14

[8] Gra Y.D. 66:12

[9] Rema Y.D. 66:8

[10] Aruch Hashulchan 66:32

[11] Teshuvot V'hanhagot 2:384

[12] Rema Y.D. 66:8, Vayevarech David 2:92

[13] Har Tzvi Y.D. 73

[14] Rema Y.D. 66:4, Aruch Hashulchan 66:27,32

[15] Yechave Daat 3:57, Igrot Moshe O.C. 3:61