New York – There has been, of late, a huge debate in the Orthodox Jewish world regarding the permissibility of certain types of fish that are infested with worms. Some may dismiss this as an old story—but it is not. Much research has been done for this article, and a video will soon be made available.
Some rabbis say that the worms under discussion are kosher (as long as they do not actually leave the fish). Other rabbis are adamant that these worms are, in fact, completely forbidden. None deny, however, that these particular worms are found in otherwise kosher fish—and they are found in abundance.
The particular type of worm in question is called Anisakis. Those who say that it is permitted believe that the worm reaches its recognizable form within the flesh of the fish itself (“Mineih Gavlei,” in the words of the Talmud, Chullin 67b), rather than having entered the fish from the outside. Those rabbis who forbid it claim that the Anisakis worm originates outside the fish and goes to the stomach of the fish; from there, apparently, the worm will migrate to the edible flesh of the fish unless the fish is immediately gutted or frozen after being caught.
The lineup of rabbis on each side, thus far, is quite impressive. Forbidding it are Rabbi Gershon Bess from Los Angeles and the top poskim of Israel—Rav Elyashiv and Rav Vosner of Bnei Brak. Permitting it thus far are Rabbi Yisroel Belsky of the OU; Dayan Yechezkel Roth, the former Satmar Rebbe’s dayan; and Rav Shlomo Miller of Lakewood and Toronto.
But does everyone agree to the facts behind the issue—before we get to the discussion of the halachah? To personally ascertain what the facts are in regard to this parasite, while in Eretz Yisrael for a yahrzeit this author spent a day at the Machon l’Mitzvos ha’Tluyos BaAretz in Beit Uzziel. The machon is under the direction of Rav Shneier Zalman Revach. It is a fascinating place, with microscopes that have a computer interface, special light boxes with both fluorescent and ultraviolet bulbs, and many roomfuls of seforim and responsa that the machon has published. The machon is housed within a revitalized religious moshav that was established at about the same time as the founding of the State of Israel.
Under a light at the machon, we proceeded to pull out numerous Anisakis worms from different types of fishes. After seeing these worms firsthand and where they are located, both in the fresh fish and on tapes and photos from the boats, it is vividly clear that the worms found in the flesh actually have migrated from the stomach—meaning that they have been ingested by the fish from the outside. (I pulled out one of those worms myself; indeed, a test tube filled with spiraled-up Anisakis worms pulled out during my visit lies in my front pocket as I write this article.)
After the fish have been partially cleaned out or gutted, there are still dark portions of the gut remnants that are attached to the inside part of the stomach’s flesh. Worms that are there cannot go back into the no-longer-existent gut. They therefore worm their way into the flesh of the fish. Many of the worms are fully through; some are halfway through, some three quarters. It is all very interesting (and all very gross).
This being the case—that the origins of this parasite and the manner in which it enters the fish is now known—the position of those that permit the consumption of fish infested with these worms seems to be quite tenuous.
There is another issue, too. Even if the worms would be considered kosher, the halachah states that if someone is personally disgusted by the consumption of the worms then it is forbidden to eat them.
One might have been tempted to read the Shulchan Aruch as permitting even the Anisakis worm. How so? The Shulchan Aruch (Y.D. 84:16) rules that worms that are found in the mei‘ayim (gizzards) of the fish are forbidden; if they are found in between the flesh and the skin or in the flesh, they are permitted. There seems to be a statement here that all worms found in the flesh are permitted. However, if one actually saw the worm proceed from the gizzards into the flesh, then clearly the Shulchan Aruch would not have permitted such a case.
Some maintain that the Shulchan Aruch’s wording seems to be stating categorically that worms do not migrate from the gizzards to the flesh. Because if they did migrate in such a way, the Shulchan Aruch would not have given tacit permission to consume worms in the flesh. Since we do not at the drop of a hat say “nishtaneh ha’teva”—nature has changed—in regard to halachah, some maintain that we may still follow the ruling that worms found in the flesh of the fish are permitted.
Rabbi Revach maintains that the issues regarding the kashrus of the Anisakis worm have no bearing on whether one says that nature has changed. He says that the Shulchan Aruch was only referring to a type of worm that is found in the flesh—not one that migrates there afterward because of faulty fish processing. The fault in the fish processing lies in only partially cleaning the fish. When we partially clean the gizzards, but do not make sure that the gizzard remnants are all clean, the worms located there could migrate into the flesh. In Talmudic times, Rabbi Revach maintains, it is likely that homemakers thoroughly cleaned out the gizzards themselves.
Is it possible for those who wish to avoid eating these worms still it the fish? Can the fish be cleaned? Yes. The seasoned inspector can look at a completely skinned fish in 65 seconds if using a light box. Red fish, however, would require an ultraviolet light and need about 90 seconds to inspect properly.
The title of this article is “Fish and Worms: The Bottom Line.” What, then, are the conclusions of this article?
Before we get to that, let’s go over a few points:
1. As of this writing, the major kashrus agencies in America are not yet committed to ensuring that our fish are free from the Anisakis worm.
2. It is this author’s contention that anyone who is shown the fish gizzards with the worms, the non-frozen fish that is partially gutted, and the fish on a light box will be conclusively convinced that these worms are not kosher.
3. Some species of fish, and fish from certain countries, simply do not have the Anisakis worm. This is either because the waters do not have it or because the fish is frozen so quickly after the gizzards have been removed that the worm has no chance of migrating.
Below is the current status of each type of common fish regarding Anisakis infestation, as of this week.
Tilapia fillets have no Anisakis (even those from China).
Hake fillets from Argentina: without skin, they have no Anisakis; those with skin are problematic. Hake fillets from China, even without skin, are problematic.
Halibut (from all countries) must be roughly scraped and then thoroughly cleansed.
Pollack from China are infested. With skin, they may not be used; fillets without skin must be inspected on a light box.
Tuna cuts and slices are free of Anisakis.
Mackerel fillet sides must be scraped and thoroughly cleansed.
Herring fillet sides must be scraped and thoroughly cleansed.
Norwegian and Chilean salmon are free of Anisakis but may have external lice. The fillets must be defrosted and rinsed, and the skin must be scraped or brushed. Chinese, American, Canadian, and Japanese salmon fillets may not be used without inspecting on a light box. Farmed salmon in the U.S. is okay.
Sardines from Morocco are okay. All others must be scraped, brushed, and washed off thoroughly.
Skinless flounder fillet from the Netherlands is free of Anisakis. Flounder from China must undergo examination on a light box. Flounder with skin from China is unusable; from the Netherlands, it must be defrosted, rinsed, and brushed to remove external lice.
There are other types of less common fish as well; please inquire about them.