Hi my name is Dan, and this video supports my online sushi course on Udemy.com
And you can learn more about the video lectures in the link below.
There's nothing quite like the vibrant color of tuna.
And sublime taste is one of the reasons why it's a favorite among sushi eaters.
In this lecture, you'll learn how to buy a sushi grade tuna,
learn how to break it down,
and understand the differences of each unique cut.
And before we get started, I think it's important first that you learn some basic purchasing guidelines.
One of the most important factor is understanding the color.
Fresh tuna will have a beautiful deep red shade.
And as the tuna ages and gets exposed to the air,
the meat will start to turn darker and eventually to a brownish tint.
This doesn't mean the tuna is spoiled, it just means his past his prime and no longer sushi grade.
And second unknown to many people,
there's a lot of processed tuna in the market that sometimes advertise as fresh.
These tunas have been treated with carbon monoxide gas to retain a color
and then vacuum-sealed.
And to on experience eyes it can be quite difficult to tell the difference between treated versus natural tuna.
And in the comparison, you can tell that the CO treated tuna has a bright pinkish color,
compared to fresh tuna whereas the meats more of a blood red.
And normally, when you're buying tuna at the store, it's already been broken down into different cuts.
And to help you understand, here are a couple of illustrations.
This is a cross-section of the belly quarter and this is where the most desirable part of the tuna is located.
Known as the O'Toro.
This part has the highest concentration of fat and commands the best price.
Now, here's a different cross section cut without the belly tag,
and the part above the skin, is known as the Chutoro.
This is considered medium fatty tuna but not to the same extent as the O'toro.
And keep in mind most smaller fish will not have any fat in this area.
So the quality is highly depending on the size of the fish.
And the third cut, known as the Akami, is the muscle closest to the spine,
and this is the leanest part of tuna and also the most affordable.
So now that you know how to buy tuna. Let's learn how to cut it.
And the way that tuna is cut, is that the processor will fillet each fish into 4 quarters,
2 top sides and 2 bottom loins.
From here on, the Seller will break it down even further depending on what the customer wants.
Some will request for the whole loin or only parts of it,
For demo, I'll be using only a section of Yellowfin Tuna loin.
Since each tuna quarter can wait quite a bit, chances are you won't need the whole thing.
Instead, just request for a smaller section.
And it's important you avoid using the tail end piece because this section has too much sinew,
and it's harder to work with. So try to avoid buying this part for sushi.
And also, request the fishmonger to remove the blood line in the skin. Since these parts won't be used.
To start dry off the loin as best as you can with paper towels on all sides.
And you can see this piece already has a bloodline and the skin removed before it was purchased.
Next, use the Yanagiba and cut off the Akami half first, roughly about 1/3 from the top.
Then turn the loin lengthwise, and start cutting block pieces about 1 inch thick.
And make sure you're cutting parallel to the loin.
This type of cut is also known as Saku, in Japanese,
and it's how the Chutoro is portioned on a larger fish.
However, this Yellowfin tuna that I'm cutting was way too small to have any fat.
And that's why every piece you see is very lean.
But if you're somebody that enjoys red tuna, then yellowfin and blackfin tunas are good choices.
And when you cut down to the last piece, this part will have stronger connective tissues,
and its best reserved for making spicy tuna or hand rolls after it's been scraped.
Which is something you learn how to do later.
And looking at the comparison here, you can see the Saku on the right has much less noticeable sinew.
And this is the part that's best saved for nigiri and sashimi applications
And after you're done portioning, it's important to go back to each piece and
trim out any bloodlines that was left behind from the store.
And also, go through each Saku block and remove any parts where the sinew is more pronounced.
Normally, the part closest to the skin, is a little bit more fibers, especially on larger fish
And a helpful tip, is to keep all the trims in a separate dish as your cutting.
This way later you can cut them all into smaller pieces so don't discard these.
And don't forget, the Akami half that you cut off earlier
can be reduced down even further into smaller pieces.
And by the way, this part of the fish is the leanest and most tender.
And as you can see there's almost no visible connective tissues compared to the others.
So after you make all your cuts you end up with several different pieces.
On the right, are cuts that are ready for making nigiri or sashimi.
And on the left, are trims with strong connective tissues.
And this will require a little more work before you can be used.
And before the tuna can be story in the fridge,
it's important to seal them in saran wrap to prevent it from drying out.
Now if you don't plan on using them within the same day,
then I suggest wrapping them in deli paper to help keep it dry while it's in the cooler.
Once these are store in the fridge it's best to use them within
three to four days before they start to change color.
And also, it's a good idea to change the paper every other day to help keep it dry.
Because remember, water and protein is a bad mix and you want to try to keep the bacteria level low.
There are some chefs that will sprinkle a touch of salt over the fish for this purpose,
so this is an option if you want to try.
And as mentioned before, the trimmings ever removed earlier can be used for
sushi rolls once it's cut up into smaller pieces.
this way it won't be tough to chew.
Now, the part with the strongest sinew needs to be scraped off.
And to do this it's easier to fillet into thinner pieces,
then knock down with the back of a knife to help loosen up the muscle.
And then use a spoon to scrape off the meat.
And as you watch, you can see that the goal here is to separate the sinew from
the meat as cleanly as possible. This is what many sushi restaurants use for
making sushi rolls or tuna tartar. And you can do the same thing too.
Now depending on how much tuna you're working with, you may end up with quite a bit of spoon meat.
And if you don't use this within the same day.
It's best to freeze them to prevent it from oxidizing too fast. Because they'll turn brown really quick.
And the best solution is to pan it over deli paper and then saran wrap it.
This way the core will freeze within minutes instead of hours.
This is really important if you want to preserve the color and quality of the tuna.
Because if you want to freeze this as a block, the core will turn brown.
And when you're ready to use it just take it out of the freezer and defrost it for a couple of hours.
I suggest reason that no more than a week.
And before I end the lecture, I think it's a point that you know what species of tuna are often used in sushi.
The three most common tunas are:
Bluefin
Bigeye
Yellow fin
And the price is based on the specie and grade.
But you can be sure that Bluefins will always come in the highest price and chances are you won't
be able to find these in your retail stores. Because most are shipped to Japan
or end up in high-end restaurants.
But on the other hand, Bigeye and Yellowfin tunas are more widely available,
and odds are this is what your local store will carry.
And aside from different species affecting the price,
there's also a grading scale that cell is used to evaluate the quality of each fish.
And this is depending on the color, clarity, texture, and fat content.
And the grading system is based on a number of ranking order, with 2 being the worst and 1+ being the best.
And generally only #1 fish are used for sushi.
Okay, that's it for this lecture, I hope it gave you some good insights so that
way the next time you go shopping for tuna you'll have a more educated mindset.
And in the next lecture, you'll get to learn how to break down entire salmon.
Okay, I hope you enjoy this video this is actually a preview of my course on Udemy.
If you want to learn more on how to make sushi at home please check out the link in the box.
There are over 40 video lectures that cover many of the basics,
such as learning how to cut vegetables, making sushi rice, how to make different
types of sushi rolls, and learn how to cut fish for nigiri and sashimi.