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  • Kashrus Awareness Staff

Teach a Man to Fish

Join Rabbi Daniel Senter, Chief Operating Officer of Kof-K Kosher, and Rabbi Yitzchok Hisiger, as they discuss the kashrus status of various species of fish and what you need to know when you go fishing.




Rabbi Yitzchok Hisiger: Thank you for joining us, Rabbi Senter.


Rabbi Daniel Senter: It is my pleasure.


Rabbi Hisger: I’d like to tap into your knowledge on the intricacies of kosher fish. If someone goes fishing and catches some fish, how can they know if their catch is kosher?


Rabbi Senter: That’s an excellent question. For fish to be kosher, they need to have two simanim - which is really one and the same. They need snapir v’kaskeses, fins and scales. Everything that swims in the water has fins. In fact, the tail itself is actually a fin. The scales are what identifies a fish as kosher.


It is not as simple as taking a look and seeing that there are scales because not everything that I’d consider to be scales are actually scales. A scale has to be an armor-like substance on top of the skin that can be removed without tearing the skin. If you catch a fish and want to know if it is kosher, the best ways are if you can see the scales and know how to identify kosher scales, or if you are familiar with this particular species of fish.


As an example, there is a common fish that is called a trout. On the trout, you can see clearly where the scales are. The other advantage is that I know that trout are kosher and I know that this is a trout. So, if I go fishing and I catch a trout, being that I know that trout is a kosher species and I know that this is a trout, I can eat that fish.


There is actually a fish in the ocean known as a sea trout. It happens to also be kosher but it has no relationship to the standard trout. This shows why you can’t rely on the name alone. You have to be familiar with the particular fish.


The trout is a good example of a kosher fish, however it’s not always that clear. There is a fish called the Spanish mackerel. If you look at the skin, it is completely smooth. This is actually a kosher fish.


Mackerel is related to tuna, although not closely related. When they come out of the water, they shed their scales. If you caught this fish, most people would say it isn’t a kosher fish. But if you’re familiar with mackerel you would know that it is a kosher fish and it may be eaten.


Rabbi Hisiger: Which part of fish do scales have to be on? The entire fish?


Rabbi Senter: As long as you find one scale on the fish, it would be good enough. As I said, some fish shed their scales. On those fish, you’ll normally find scales in covered, protected areas of fish. But there are fish where the scales are very obvious.


A tilapia is a fish where you can clearly see the scales. Carp is also a common kosher fish that people catch. Those have huge, developed scales. Fish like tilapia and carp are very easy to tell that they are kosher fish. Other fish, like the mackerel, are not as easy.


The general rule of thumb would be to know your species. If not, be cautious and ask a question. I don’t mean that you have to ask your Rov if this is a kosher fish. You can ask a fishmonger what species this fish is and he can tell you.


There are many lists of common kosher fish available. There are thousands of species of fish. Some of them are kosher and some of them are not. It would be far beyond us to publish a list of all kosher fish but we can publish lists of those that are commonly available. There aren’t that many. If you go to the northeast, there are about 30 or 40 different kinds of fish that are commonly available. If you are familiar with those and know, for example, that a bass is kosher and catfish is not and you know how to identify them, you’ll be able to make the decision yourself about the kashrus status of the fish.


Rabbi Hisiger: When a store sells fish under a certain label, can I trust them and assume it really is what they say it is?


Rabbi Senter: At one time, when fish was very inexpensive, you were safer doing that.

The crazy thing is that fish was always the poor man’s alternative to meat. Today, fish is more expensive than meat, especially certain varieties of fish.


As our oceans are overfished, certain species of sought-after and targeted fish become harder to get and, therefore, are commonly switched. A great example of that is sable. Sable was a very popular fish and many people enjoy kosher smoked sable. As it became more expensive, Chilean sea bass was a good alternative because it tastes similar. They are both kosher fish, so it wasn’t a kashrus problem. But it was a Choshen Mishpat shaila people thought they were getting one fish and were getting another. What happened, fortunately or unfortunately, is that Chilean sea bass has caught up to the fish it was being used as a substitute for. So now you’ll probably end up with the right species, identified the right way.


Rabbi Hisiger: Do I have to be worried that the company is adding ingredients to the fish?


Rabbi Senter: Yes and no.


I very often get calls from people who buy fish that say “color added”. These calls are often about salmon. Salmon outsells all other fish in America by about 5 to 1. We eat a lot of salmon. Most of our salmon, though not all of it, is farm raised. How does salmon get its pink or red color? From eating animals in the ocean like shrimp that have beta carotene in them. You will sometimes see on salmon labels that it says “color added to feed”. That sounds like they’re coloring the fish. But what they actually do is feed the fish beta carotene. By law, they have to write “color added”. That would not be a problem.


Sometimes, however, they will add seasoning to fish. And when they want to freeze fish, they will sometimes put it in a coating. Very often, the coating is just corn syrup, which would not be a problem other than on Pesach. But one has to be careful.


Rabbi Hisiger: Is the coating a preservative?


Rabbi Senter: What they want to do is give it a glassy coating. Putting a little bit of corn syrup or a little starch will give fish a nice shiny glaze when they want to freeze it.


Seasoned fish would obviously be a problem. In regular fresh, raw fish without anything listed as additives, we haven’t really found a problem of added ingredients.


Rabbi Hisiger: Is there a concern that the company may be adding a piece of skin or scales back onto fish?


Rabbi Senter: So far, we have only discussed whole fish. Another option is buying fish with the skin on.


We’ve gotten used to eating fish without having to be bothered with the bones. The fish is fileted for us, meaning that the meat is taken away from the bones. Sometimes, when a fish is fileted, the skin is also taken off. If the fish has no skin, catfish and tilapia look almost exactly the same. Because of that, fish without skin is not acceptable and would be considered non-kosher. But if the skin of tilapia is left on, it is very identifiable as a kosher fish and that would be enough to buy it.


If a company says they will leave the skin on, you can trust them because they sell it by weight and if you pay for the skin, that’s additional money for them. So, you can rely on that.


The problem we have created is that we’ve become lazy. People not only do not want bones. They also do not want skin. So companies will take off the skin and just leave one little skin tag in a corner. Theoretically that would be a good siman of kashrus. However, we’ve had cases of frozen fish with skin tags on that look kosher, but if you look closely, you can see that it is only frozen together to the fish a little and not totally attached. Why would a company put a skin tag of a kosher fish on a non-kosher fish? Because catfish only costs about two dollars a pound. It would be a big yeitzer hara for them to substitute it for a more expensive, kosher fish.


Rabbi Hisiger: Can the layman tell if the skin tag is from a different fish?


Rabbi Senter: If it comes off too easily or it looks like it’s in the wrong place, that’s something you should be concerned about. I wouldn’t say it’s a common problem but one should be careful.


More importantly, one has to realize that just seeing skin on a fish doesn’t make it kosher. Non-kosher fish have skin too. There needs to be enough skin to recognize that it is a kosher fish, by checking for scales on the skin tag.


Rabbi Hisiger: What is the strangest shaila you’ve ever received in regards to fish?


Rabbi Senter: We received a phone call from a very irate customer in a restaurant. He had ordered a sea bass and was served a whole fish on a plate to his table. The fish’s last meal was stuck between its gills. Basically, he was served a fish with a shrimp in its mouth. We had a whole shaila about the keilim, etc.


As far as fish are concerned, this was the most bizarre shaila I ever got. Would I tell you that you have to check the mouth of every fish? No. I would say that this was a one-in-a-million case.


Rabbi Hisiger: As we try to do in these segments, can you please give us your “Let’s Talk Kashrus” takeaway for the people at home?


Rabbi Senter: The takeaway is that before you assume that something is kosher, it is important to know what makes the fish kosher. More importantly, it is upon us to recognize what makes things kosher and not kosher.


We tend to rely on everyone else and want to do less ourselves. It’s important for us to learn and know on our own, so that we can take the achrayus of kashrus on ourselves and make sure that whatever ends up on our plates and in our homes is kosher.


Rabbi Hisiger: Thank you Rabbi Senter for this educational and entertaining lesson.


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