Question: Ask the Rabbi - What makes milk kosher?
Some milk gallon bottles have kosher symbols, like KD or triangle-KD. What is the difference between milk bottles with kosher certification versus milk bottles without it? Are dairy plants using emulsifiers or animal protein in processing cow milk?
Thank you, Faisal
Answer: Dear Faisal,
Thank you for writing.
The kosher symbol "K" on milk cartons means that the company processing the milk works under rabbinical supervision.
The rabbinical supervision checks that no non-kosher additives or non-kosher processes were used in producing the milk.
The kosher symbol "KD" simply means that the item is under rabbinical supervision, as explained above, and that the product is dairy.
To the best of my knowledge, there are no additives to the milk product itself. However, to be certain of this, I suggest that you contact the company producing the milk in which you are interested. Likewise, it is best to ask them if they use either animal protein or emulsifiers.
As long as we are discussing kosher milk, I wanted to mention the concept of Cholov Yisroel. An ancient rule required that a Jew must be present from the time of milking to the time of bottling to ensure that milk from kosher animals did not become mixed with milk from non-kosher animals. Milk that is observed in this way is referred to as Cholov Yisroel, and some orthodox Jews will consume only Cholov Yisroel.
However, in the United States, federal law relating to the production of milk is so strict that many Orthodox sources accept any milk as kosher.
I hope that this is helpful.