Pickled Herring Sushi using Rollmops
This dish is inspired by a traditional Japanese form of Sushi in which lightly pickled Mackerel fillets are pressed atop blocks of Sushi Rice. I love the very delicate flavor of Japanese style Mackerel pickled with Salt and Rice Vinegar, but I thought the Western, more aggressively pickled, Herring fillets known as ‘Rollmops’ would work nicely too.
What are Rollmops?
For those unfamiliar, commercially Pickled Herring typically consists of small squares of salted Herring pickled in sharp White Vinegar (sometimes with wine), along with Onion and Black Peppercorns. Frequently, it is sweetened with a little sugar as well.
There is, however, a variety of Pickled Herring in which the whole fillet is rolled around a sliver of Gherkin and then Pickled in the usual style. I had always heard that the style is of Dutch origin, but the name, at least, is German. According to Wikipedia, it is ‘derived from the words rollen (to roll) and Mops meaning fat young boy. The form Rollmops is singular, and the plural is Rollmöpse’.
Above, you can see a jar of Rollmops Pickle with a single ‘roll’ beside it, and an unrolled fillet in the foreground with the Gherkin piece removed. As this was not required for the preparation of the Sushi, I ate it before proceeding.
The Sushi Press
If you are extremely well practised at making Sushi, you might be able to get away with making your Pickled Herring Sushi using a traditional Japanese Makisu rolling mat. However, since the blocks of formed Sushi need to be pressed, using a form of some type is advisable.
Above, you can see the wooden form that I used for this dish. I found it in the ‘bargain bin’ of a store somewhere (I think) in Ottawa, but you should easily be able to find an equivalent online. Alternatively, if you are somewhat handy in the woodshop, knocking together a device of your own shouldn’t be too difficult.
How I made my Pickled Herring Sushi
The Rollmops absorb a lot of pickling liquid in their jars and so I pressed my trimmed pieces between two boards, using a little weight to really squeeze them. My aim here was to prevent the sushi rice from getting way too soggy.
You will note, in the above picture, that one end of the boards have been raised with a chopstick to allow the expelled liquid to run off. You can see that this is being absorbed by the paper towel at the right.
To make the Sushi blocks, you obviously need to prepare a batch of Sushi Rice. I made a cup of finished rice and had more than enough to make one ‘block’. I required two Rollmop fillets, both of which needed to be trimmed to fit the mold. In the background, you can see the ‘squared off’ sections with the trimmings just in front of them. The trimmings went the same way as the Gherkin.
I only filled the mold about 2/3 full as the fillets are quite thick. As you can see, I lined the mold with clear plastic wrap before filling. This helps with the clean-up afterward.
The fillets went on top of the rice and, after taking this picture, I folded the plastic wrap over top before inserting the ‘pressing bar’.
I pressed the block for a whole afternoon while doing other tasks. One of the good things about this type of sushi is that, along as you keep it tightly wrapped, you can put it in the refrigerator to slice later. Naturally, this allows you to do a lot of work ahead of actually serving.
Here is the block unwrapped and ready for slicing. The mold did a very nice job, I think.
Instead of Soy Sauce and Wasabi, I served my Sushi slices with a very light sauce made with Mirin, and a little splash each of Lemon Juice and Soy Sauce, and, overall, the effect was pretty good. Each slice is garnished with a small wedge cut from a thin Lemon slice.
Surprisingly, the fish was not nearly as assertive as I was expecting and I think expelling a lot of the pickling juice had that effect. In consequence, the taste was much closer to Japanese pickled Mackerel than I anticipated. Next time, I may try a little wasabi on the fillets before assembling the blocks.