Question:  Why would mozzarella cheese be considered not kosher, thusly making a slice of pizza treif?

Answer: Cheese is made by putting an enzyme into raw milk, causing it to curdle.  The most common source for the enzyme (also known as rennin or rennet) is from the stomach lining of cows.  The stomach is dried and ground into a powder, and mixed with other chemicals and liquid - and a small amount of the new compound is placed in the raw milk.

There are two common opinions about the use of such enzymes to make cheese.  According to one opinion, the cheese is non-kosher because of the forbidden mixture of milk and meat.  According to the other opinion, once the stomach lining becomes completely dry ("like wood," to use the language of the Shulchan Aruch, an authoritative code of Jewish law), it is inedible and becomes a new substance, unrelated to the animal from which it came.  This new substance can be considered kosher and parve, and according to this understanding, any domestic hard cheese is kosher.  Imported cheeses still may make cheese the old fashioned way - using a fresh piece of stomach lining, rendering the cheese absolutely non-kosher.  Today, generally in health food stores, it is easy to find cheese made with microbial rennin or enzymes which are grown using bacteria rather than coming from an animal, and are certainly parve.

The question about pizza is more complicated.  To determine the kashrut of pizza, you need to take the composition and preparation of the sauce and crust into account, as well as all of the toppings, and the surface of the oven upon which it was baked.

Question:  Are you allowed to eat reindeer if you live in Alaska?

Answer: Their are two signs of a kosher land animal:  it must chew its cud, and it must have split hooves.  If a reindeer has these signs, it is kosher.  If it does not, it is not kosher.  It actually would not matter where you lived - you could live in Florida and eat reindeer!

Reindeer is such an animal, related to the deer and the caribou, which has the signs of a kosher animal.  But one more thing has to happen for us to eat kosher reindeer - it must be slaughtered by shechita, kosher slaughter.  This is very difficult to do with wild reindeer, but if you were to raise domesticated reindeer and take them to a kosher slaughterhouse, then people around the world could enjoy their meat!

By the way, I don't know anyone who raised reindeer for kosher slaughter.

Question:  Why isn’t ostrich kosher?


Answer: Ostrich is non-kosher because the Torah lists it among the impure birds in Leviticus 11 (vs. 16) and Deuteronomy 14 (vs. 15).  The Torah does not give a reason for classifying certain birds as non-kosher, but it appears that virtually all impure birds are scavengers or birds of prey.

Question:  Thank you for your reply.  I knew what you wrote, what I really wanted to know is: is the hebrew for Ostrich definitely the same bird we know of today and is there possibly an historical as well as Toraic reaason why this is so about Ostriches, since as I understand this they are not really scavengers, or birds of prey, although they are not nice birds and can get rough if they are approached by humans, i.e. biting them etc. However, they do not eat or hunt other animals. I understand they are used for racing and were used, historically by the Romans  in ancient times for targets and for racing as well.  It’s just an interesting thing to think about the whys. I understand that the explanation may  just be because it says so, but, sometimes one thinks about other possibilities.


Answer: Every translation I looked at translated the word shalakh as ostrich.  However, in Baruch Levine’s JPS Torah commentary on Leviticus, he writes that a shalakh is a “fish owl, ostrich” and notes that it is a nocturnal bird of prey.  I don’t know enough about the diet or lifestyle of an ostrich to be able to answer your question any more definitively.  Remember, however, that the Torah does not give a reason for declaring certain birds tameh (ritually impure), and no explanation that we impose upon the Torah’s list of tameh birds fits perfectly.

Question:  Is it permissible for me to buy pre-sliced or fileted salmon steaks from the supermarket - or must I buy the whole fish and filet it myself?


Answer: There are some people who will only buy a whole fish from a non-kosher supermarket for reasons of kashrut.  Other people have an agreement with the butcher in which they bring in their own knife for the butcher to clean and filet a whole fish, which they then purchase.

However, I do not think either approach is necessary.  According to halakha,  utensils are made dairy, meat, or 'trafe' through heat.  In other words, if a spoon is put into a hot bowl of chicken soup, it becomes a meat spoon (or it becomes trafe, if it was previously dairy).  However, if a meat spoon is put into a cold bowl of milk (by accident), it may be removed and rinsed with cold water.  It does not become treif.

Since both the knife and the fish are cold when the butcher is preparing it, there is no issue of making the fish trafe, no matter what the knife was used for previously.  I would inquire, however, whether the knife was washed thoroughly before cutting the fish, just in case whatever was cut prior to the fish was treif.  In addition, just to make sure, I would wash the fish with cold water before cooking it, to rinse off any possibly treif food residue.

Question:  I am going to barbados in the Caribbean and want to know if the following fish are kosher:  flying fish and dolphinfish?


Answer: Both flying fish and dolphin fish (although not the dolphin!) are kosher.  Enjoy your vacation!

Question:  Under the laws of Kashrut are we allowed to eat catfish?


Answer: According to the halakha of kashrut, which states that kosher fish must have both fins and scales, catfish is not kosher.

Question:  I would like to know if the fish orange roughy is kosher?


Answer: Orange roughy has both fins and scales, thus making it a kosher fish.

Interestingly, however, I could not find it in my usual reference book, The Jewish Dietary Laws, by Samuel H. Dresner, Seymour Siegel, and David Pollack, revised and expanded in 1982.  It was either known by another name or was not a well known and popular kind of fish when the reference list was put together.

Question:  Are Power Bars kosher?   If not is there a similar product that is? Are any of these products Kosher for Passover?


I'm not sure whether Power Bars are kosher or not -- if you look at the label, there will be a kosher certification symbol if they are kosher.  Actually, I don't know what Power Bars are, so I cannot recommend a substitute.  I doubt if they are kosher for Pesah.  If they are, the kosher supervision symbol would specifically say kosher for Pesah.

Question:  I just bought two packages of dried fruit at Trader Joe's (Torn & Glasser is the trade name of one and Trader Joes the other), and later noticed that there is no kosher symbol on either label. Even though I know that fruit is kosher, this is dried fruit and includes potassium sorbate as a preservative as well as sulphur dioxide for color retention. Are these products kosher?


Answer: Without a kosher symbol on the label, I cannot recommend the dried fruit as kosher.  You might call the company and ask them if they have kosher supervision - sometimes a company will have supervision, but will not have put a kosher symbol on the label.

The problem with dried fruit is that they are processed in some way, possibly dried in ovens, and I don't know what that processing involves.  It might involve non-kosher oils, there might have been other, non-kosher products on the same trays or in the same ovens.  It is also possible that there are trace ingredients which are added to the fruit in such small quantities that the USDA or FDA does not require them to be listed on the labels, and such ingredients may be non-kosher.  Finally, it is even possible that the fruit might be kosher but dairy, because the trays/ovens were used for dairy products as well as fruit.

Question:  I want to know if coconut milk is considered milkhik because it looks like milk but since it comes from a coconut and  a coconut  is a fruit which is then pareve. If it is pareve, can it be used lets say on meat products?


Answer: Although coconut milk looks like milk, it is not.  It is indeed a parve substance, since is comes from a fruit.  Realize, however, that it is an oily sweet substance, and probably can not be used successfuly as a milk substitute!

Question:  Do you know the original reason why crops infested with insects were not permitted for human consumption?  My secular, scientific education lead me to believe that insects would attack the healthiest and most desirable crops, and that is why we needed to spray pesticides.  What I have observed in my work, however, is that insects seem to attack the least vigorous and least healthy crops and seem to be most active in the least fertile soil.  I'm wondering if our ancestors may have observed the same, and consequently took that to mean that crops infested with insects were not nourishing enough for human consumption.


Answer: I think it has nothing to do with the condition of the crops themselves.  Rather, since insects are not kosher (with one exception, a certain kind of locust), if a plant is infested to the point that the insects cannot be removed, then the plant could not be eaten without ingesting non-kosher insects.

By the way, I can think of no Biblical source that insect infested plants per se are forbidden to eat.  But I do know that within the kosher establishment today, there is an assumption that certain vegetables (lettuce, brocolli) are assumed to be non-kosher because they contain insects, unless they are very carefully cleaned.

Question:  Please answer a question for me.  I received a pastry brush as a gift. However, its bristles are boar bristles.  Is this item
treif?  I keep a kosher home and do not want to prepare any food, with this brush, if it will render any food it touches treif.


Answer: You may use a boar bristle pastry brush without worrying about it rendering the food it touches treif.  Basically, it is not forbidden to benefit from products that come from non-kosher animals as long as you do not eat them.

I must admit, that my first reaction to your question was "Yech!"  Personally, I would not use such a pastry brush, because the thought of spreading my food with pig parts is somewhat revolting, but that is an emotional, rather than an halakhic, argument.

The only concern that remains is whether the bristles are likely to begin falling out, in which case there is a real possibility that one might ingest them.  However, another principle of kashrut teaches that anything which is not eaten as food, such as a dried up piece of stomach lining or a moldy piece of bread, is no longer governed by the laws of kosher and treif.  Therefore, boar bristles would probably not be treif even if you accidently ate one.  But again - "Yech" - if shedding bristles is a possibility, I would not use the brush.

Question:  this may sound like a ridiculous question, but I am quite serious. I am a 45 year old Reform Jewish woman marrying a man who was raised Conservative.  He has kept a kosher home most of his life.  As it happens, I happen to like the artistic image of pigs. I have collected all kinds of pigs, including an expensive painting of a pig that I love.  We are marrying in june and moving in together.  As a Jew, he finds my painting offensive and would not feel comfortable hanging in our home.  I am wondering from a religious standpoint if you would agree and find it offensive also (it a a very beautiful and funny painting).  We had a debate tonight over it, over the legitimacy of his feelings.  I wonder if you or another rabbi or religious/observant person would feel the same way.  It made little sense to me.  Then, I reminded him that he has live shrimp in his aquarium and i don't really know if that should be anymore acceptable from a "religious standopint" than having a pig painting hanging in your home.  please give me your opinion on this silly debate.


Answer: Several years ago I answered a question on AskaRabbi regarding the permissibility of using a pastry brush made with boar hair bristles.  My answer also applies to your question.  I wrote (in part):

You may use a boar bristle pastry brush without worrying about it rendering the food it touches treif.  Basically, it is not forbidden to benefit from products that come from non-kosher animals as long as you do not eat them. . . .  The only concern that remains is whether the bristles are likely to begin falling out, in which case there is a real possibility that one might ingest them.  However, another principle of kashrut teaches that anything which is not eaten as food, such as a dried up piece of stomach lining or a moldy piece of bread, is no longer governed by the laws of kosher and treif.  Therefore, boar bristles would probably not be treif even if you accidently ate one.

From a religious point of view, there is nothing treif about looking a pictures, sculpture, figurines, or any other images of pigs (or shrimp, rabbits, camels, horses - land or sea, etc.).  However, I am not going to take your side quite so easily in this argument.  Let's say you have a beautiful signed print of a Salvador Dali -- one with bloody, dripping human figures.  Let's say that your fiance finds it revolting.  How do you decide where (if anywhere) to display it?

What you have encountered is a marital issue, not a kashrut issue or an issue of whose taste in art is more correct.

Is it the case that if he marries you, he marries your pig collection?  Is it the case that if you marry him, you alone determine the living room decor?  Is there a way for the two of you to compromise, perhaps by selecting one room of the house as the "pig room," that you decorate, that perhaps is not the living room or the kitchen, where you entertain guests, or the bedroom, where he would need to look at the pigs fairly often?

I'd like you to use this argument as a test of how you are going to resolve other disputes in your marriage.  Rather than turn to other people to gather evidence proving who is more correct, turn to each other and see how much each of you can compromise.  No debate is necessarily silly - if this is troubling you as much as your note tells me, I'd like to suggest that the two of you get counseling before you marry.  Actually, I am not suggesting the counseling just because of your note -- I think it is critical that every couple getting married gets pre-marital counseling.

Any any case, mazal tov on your engagement, and may you have a long and happy marriage!



Question:  I'm just curious:  I read that San Chez had a special menu "try-out" of Asian Carp this past summer.  This would seem to be a good way to deal with an invasive species - eat them!  I'm curious to know if this fish is kosher.
Answer:  There are several different species of carp that are included under the rubric of Asian carp.  I found two of them in my list of kosher fish.  The two species that have been identified as the invasive species in Lake Michigan are not on the list, but neither are they on the list of non-kosher fish.  I looked up the characteristics of those two species, and am reasonably certain that they are kosher.



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