Is Sushi Kosher? Title Image

By COR Rabbinic Staff

What would Bubby say to a new type of gefilte fish? L’kovod shabbos, of course! This one will have a dark green wrapper filled with rice and your choice of a variety of delicious raw fish. The carrot will be optional.

Allow me to introduce “sushi” or, in English, “vinagered rice”. The most common ingredients in sushi include toasted nori, rice, raw fish, sesame seeds, pickled ginger, soy sauce, and wasabi (Japanese version of chrayn). Other common ingredients include avocado, carrots, cucumbers, green onions, mayonnaise and chili sauce. There are a number of kashrus concerns associated with the production of sushi and its ingredients. As such, a reliable kosher certification is required. This article will focus one concern; the potential insect infestation in toasted nori sheets.

A Nori sheet is a thin, paper-like product that is made from seaweed and is used as a wrapper for sushi. Seaweed, in its raw state, is a vegetable and is prone to insect infestation. Most commonly, seaweed may contain mini seahorses, shrimp, scorpions and other crustaceans. Infestation levels will vary depending on the time of year, growing climate and harvesting method.

Nori sheets are made using a process that takes raw seaweed, shreds it and dries (toasts) it using a rack-drying process that resembles papermaking. Hence, nori sheets are already shredded and dried. These two factors alleviate some of the infestation concerns, but research has found this alone to be inadequate.

Many companies use laser technology to remove foreign objects from nori sheets. A laser sorter senses any object that does not conform to the texture and colour of the nori. Increasing the sensitivity of these laser sorter enables it to pick out insects that remain on the surface of the nori sheets after shredding and drying. Reliable kosher certifiers are careful to use this technology to their maximum advantage.

Kashruth Council of Canada, COR, has conducted its own research study of nori sheets that bear reliable kosher certification and has found them to be free of insect infestation.

So, if it tempts your taste buds, get yourself a set of chopsticks and invite Bubby for the newest option in kovod shabbos, Gefilte Nori.