The Story of Sushi (21 page)

“Pretty good!” Kate said.

Takumi nodded. He thought the head contained the best-tasting meat because the jaw and fin muscles got constant use. He showed Kate how to pick the best morsels from the head with chopsticks. Then he fished in his bowl. He extracted an eyeball.

“This is good,” he said, and swallowed it.

Zoran called the class back into session—it was time to make sashimi and sushi with the snapper fillets. After scalding the crap out of one’s fingers, the key to presenting snapper was to put that colorful cooked skin on display.

“When Western customers see the skin,” Zoran had told them earlier, “they say, ‘Ew.’ So you have to educate the customer.”

Kate peered closely at her glistening slices of snapper. Under the textured skin, the flesh was a matrix of transparent gelatinous capsules of muscle.

The muscles of most creatures are divided into two types: fast-twitch fibers and slow-twitch fibers. Fast-twitch fibers are the sprinters—the muscles move quickly, but they also tire out quickly. Slow-twitch fibers are the marathoners—the muscles move slowly, but they keep going for a long time.

Fast muscles are light-colored or translucent. At Thanksgiving dinner, the turkey’s white meat is fast muscle—turkeys only beat their wings in short bursts. Turkeys spend most of their time walking around, which is why their legs are slow muscle. That’s the dark meat. The muscles of many mammals, including humans, are dual-use and contain both types of fibers.

Fish muscle ought to consist mostly of slow-twitch fibers because fish are constantly swimming around. But water is a weird place.
Swimming through it slowly is easy, especially if you’re shaped like a fish. But if you try to go fast, the density of the water suddenly hits you like a wall. Resistance increases exponentially with speed.

This means that for most fish, the muscles they use constantly are barely noticeable—just a thin pair of dark fibers running down each side of the body, usually right under the skin. The cross section of a salmon steak, for example, has small triangles of dark meat nestled against the skin on either side. These are the slow-twitch fibers that the salmon uses for most of its regular swimming. If fish never needed to swim fast, they’d all be narrow shafts.

The rest of a fish’s muscle—from 60 to 90 percent of it, depending on the species—is an emergency power pack of pale, fast-twitch fibers that kicks in when the fish needs to sprint. Fast-twitch fibers function well in quick, short bursts because they contain their own fuel supply of preloaded carbs. Enzymes inside the fibers convert this fuel into quick energy. The conversion occurs so fast that the fibers soon exhaust their supply of oxygen. They can keep functioning for a while without oxygen, but not for long. They soon shut down for refueling, and the sprint is over.

By contrast, slow-twitch fibers burn fat for fuel, which requires lots of oxygen. These fat-burning factories hire fleets of delivery trucks to fetch oxygen and bring it to the factory, so they don’t have to shut down. The trucks are proteins called myoglobin. Meanwhile, inside the factory, part of the machinery that uses oxygen to burn fat are proteins called cytochromes. Myoglobin and cytochromes both possess a kind of hook for holding on to oxygen. The hook is made of iron. These iron-containing proteins are red, though they turn brown when cooked. That’s why dark meat is dark.

The pale muscle Kate was looking at in her snapper consisted almost entirely of fast-twitch fiber. The category of white fish in sushi—sea bream, snapper, flounder—contain an especially high percentage of fast muscle. These fish also tend not to embark on long-distance seasonal migrations, so they don’t store up reserves of fat in their bodies as do mackerel, salmon, or tuna. For these reasons, many Japanese sushi eaters have traditionally preferred them. The gelatinous capsules of muscle in Kate’s fillet represented a lean, light-tasting meat that had an almost crunchy texture in the mouth.

The Japanese like
tai
in particular for its clean, sweet taste.
Tai
falls short on
umami
—it contains only three-quarters of the IMP of bonito. But
tai
is rich in the sweet-tasting amino acid glycine, with three times more of it than tuna.

“This is a very nice-tasting fish,” Zoran said, as he sliced pieces for sushi off his fillet. He squeezed together some snapper
nigiri
. He lined them up on a tray and placed a pinch of mysterious green paste atop each one.

“Try this,” he said.

Kate ate one. It was like nothing she’d ever tasted. There was none of the fatty richness of salmon or yellowtail. Mingled with the subtle sweetness of the fish and its skin was an unusual bouquet of flavors from the mysterious paste—notes of lime, clove, and oregano, along with a spicy zing. Her face filled with wonder. It was the most delicious thing she’d eaten all semester.

Zoran looked pleased. He revealed his secret. The green paste was a mush of the rare and flavorful Asian citrus fruit yuzu, laced with green chili pepper. It augmented the sweet snapper perfectly.

The students practiced making
nigiri
with their fillets. Kate sliced her fish with her willow-leaf knife. It was the third time she’d used it this week, but it still had a decent edge.

Zoran patrolled the room, watching the students make
nigiri
. He shook his head. They stood hunched over, turning and squeezing close to their faces like nearsighted old ladies darning socks.

“You all look like this.” Zoran slouched over and moved his arms through a series of big, plodding motions. “Stand up, hold your hands up, keep your movements small and efficient. Hold your fish up high—” he dangled a slice in the air “—then form your rice. If you need to give your
nigiri
extra squeezes because it still hasn’t formed properly, do it like this.” He stood up straight, arms cocked out in front of him, and spun the
nigiri
on his palm. “That way the customer thinks you’re busy making good sushi, not trying to fix your bad
nigiri
!”

Zoran strode to and fro, yelling like an army recruiter. “Be confident! Be proud!
I want to be the best that I can be!
”

After class, Kate congratulated herself. She’d done things today that she had no idea she was capable of doing. While the others sharpened their knives, she slipped out of her uniform and gathered up her gear and knife case. She left the apple sitting on the sushi bar and headed for the door. Zoran watched her. He’d noticed that Kate hadn’t been staying after class to sharpen her knives.

He called after her. “Sharpen your knife!”

Kate turned, but didn’t stop. “Huh?”

“Sharpen your knife tonight!”

Kate nodded. “Okay.”

K
ate didn’t sharpen her knives. She figured they were still sharp enough. When she walked into the classroom the next morning, she noticed that the apple was gone. She bumped into Zoran a few minutes later. ‘I ate your apple,’ he said.

As Zoran took roll, Kate took a swig from a tall black can. The shorter cans of Red Bull weren’t cutting it anymore. This morning she’d switched to a caffeine drink twice the size—Monster Energy. On the side of the can it said “Unleash the Beast,” which was appropriate considering what sat waiting for them today in the walk-in.

“You’re going to have fun today!” Zoran said. “What do you call yellowtail in Japanese?”

Yellowtail is one of the most popular fish in sushi. Yet even aficionados can’t agree on what it is called. For starters, it’s not to be confused with certain types of flounder and snapper that are also called yellowtail.

Zoran laughed. “This is going to get really confusing.” He wrote on the whiteboard:

• mojako
  —1 to 2 inch fry
  
• wakashi
  —2 to 6 inch size
  
• inada
  —6 to 16 inch
  
• warasa
  —16 inch to 2 feet
  
• buri
  —mature
  

Yellowtail is what the Japanese call an “ascending fish.” As the fish grows through different life stages, the name of the fish changes because it tastes different at each stage. Eating an
inada
(a young fish on its way north to feed for a few years) is different from eating a
buri
(an adult fish on its way south to spawn), even though they are the same species. The term “ascending fish” comes from an old Buddhist term referring to a young man who becomes a monk.

To make matters more complicated, people in different parts of Japan use a totally different set of names for the various stages of yellowtail. The names Zoran had listed were the ones people in Tokyo use. Around Kyoto, people divide the maturation of yellowtail not into five levels, but into seven, and use seven separate terms unrelated to the Tokyo terminology. People in other parts of the country have different names still. It’s a wonder anyone can walk into a restaurant in Japan and order the fish at all.

There is an additional complication. In western Japan, people once used the word
hamachi
to refer to the adolescent fish’s fourth stage. Zoran explained that now
hamachi
refers simply to any farmed yellowtail because farmers harvest the fish on the cusp of maturity.

“Don’t say ‘farmed,’” Zoran told them. “It sounds unprofessional. Say ‘cultivated.’”

The Japanese have long prized wild yellowtail in winter, particularly
buri
caught in the Japan Sea as they head south after several years of feeding in rich northern waters. They are firm, flavorful, and rich—nearly 20 percent fat. But they, too, can carry the parasitic larvae of the anisakis worm, and the fatty flesh spoils quickly.
Buri
weren’t especially popular for sushi.

In the 1970s, yellowtail farms began to supply large quantities of fatty fish all year long, and the Japanese began to eat a fattier diet. Now, as in America, customers at sushi bars in Japan often prefer the soft, buttery flesh of farmed yellowtail, even though they have less flavor than their wild counterparts. The farmed fish are nearly 30 percent fat. Sushi traditionalists consider this to be too
much fat. Zoran, for one, wouldn’t eat farmed yellowtail. He said it was too oily.

Zoran gave the students an overview of yellowtail farming. In the wild, the fish spawn in the sea off southwestern Japan. Their fry—the little
mojako
—mass inside mats of floating seaweed. Some seventy other species of tiny fish also live in the seaweed, but the
mojako
dominate. Fishermen easily capture them alive while each fish still weighs only a third of an ounce.

In the wild, these fry would have grown bigger and spent years swimming long distances and chasing prey as they matured into
wakashi, inada,
and
warasa.
Finally they would have come of age as
buri
and been caught as a winter treat. Instead, they will lead a life more akin to the lives that produce veal and foie gras, although with less discomfort. Like farmed salmon, farmed yellowtail are pampered and lazy—for the most part.

Fish farmers feed the fry three or four times a day. The tiny fish quickly grow to a hundred times their initial weight. The farmers vaccinate the fish because disease is a constant danger under crowded conditions, just as on salmon farms. Then the fish are transfered into floating pens.

Disease isn’t the only problem. Humans like to eat yellowtail, but yellowtail also like to eat yellowtail, which makes them a tricky species to manage. At night, when the fish stop swimming and drift at the surface, the farmers cull through them and segregate them into different pens by size, so the big fish don’t gobble up the smaller ones.

Every day the farmers fire feed pellets out of a canon into the pens. The feed pellets are similar to the ones salmon farmers use, packed with ground-up fatty fish such as mackerel, herring, sardines, and anchovies, often along with extra doses of oils and vitamins.

The yellowtail eat so much of this feed, and get so little exercise, that the excessive amounts of fat they accumulate actually weaken the matrix of connective collagen fibers that holds their muscles together. That’s why farmed yellowtail is so soft.

Independent researchers have conducted thorough investigations into farmed salmon, revealing that the fish accumulate much higher levels of PCBs from their feed than do wild salmon. So far, yellowtail have not been the subject of similar studies, even though
lots of people eat high-fat farmed yellowtail in sushi. It would not be surprising if farmed yellowtail have the same problem.

Most yellowtail served in sushi—regardless of the region, type of restaurant, or price the customer pays—come from the same cluster of yellowtail farms, located off the coast of western Japan. Farmed yellowtail now account for 70 percent of all finfish aquaculture in Japan. Only a quarter of the yellowtail on the market in Japan are still caught from the wild.

“
Kanpachi
is lean, wild yellowtail,” Zoran went on.
Kanpachi
is a closely related species to
hamachi.
“If someone wants yellowtail, but not as fishy and not as fatty, you can serve them
kanpachi.
”

But aquaculture companies have begun producing fatty farmed versions of
kanpachi,
too. Before long, the words
lean
and
wild
may not apply to fish at all.

“Today we have three fish,” Zoran said, smiling. “Three
big
fish. One of the fish is from Japan and we can eat it raw. The other two we can just practice hacking up.” The farmed fish that had arrived by plane from Japan was fresher than the fish from southern California.

Zoran pulled the fresher, Japanese
hamachi
from the walk-in. It had lost its head and organs. Its tail remained intact, though it wasn’t especially yellow. Zoran told the students that most yellowtail was shipped headless to save weight. The body was two feet long.

He laid the fish gently on a towel on his cutting board and wiped it with another towel. Kate admired its lustrous surface. It was amazing to her that it could look so fresh and have come all the way from Japan.

“A lot of American customers eat
hamachi,
” Zoran said, “but say they don’t want mackerel. It doesn’t make sense to me. I think this is more fishy-tasting than a mackerel.” He ran his hand across the surface of the fish. “First thing, take off the scales, right?”

He rubbed his scaler across the fish. Kate braced herself for the horrible scraping sound. It didn’t come. The scaler just slid smoothly back and forth. Zoran looked up at the students and smirked. “The scales are so small that this won’t work. We have to
cut
them off.”

Yellowtail scales aren’t as tiny as mackerel scales, and for a chef, that means they are inconvenient—too big to eat, too small to scrape off. Zoran used his willow-leaf knife to saw lightly across the surface of the fish, as if he were skinning a big mango. The outer skin and scales came off in strips.

“Okay, let me show you the other fish.” He led the students into the kitchen. He set a pair of oversized polyethylene cutting boards on the kitchen table, then disappeared into the walk-in.

When Zoran reemerged, he had a whole fish in his arms. The thing was three feet long. It still had everything, including its head. Zoran dumped it on one of the cutting boards with a thud and returned for a second one just like it. The tail fins on these fish were distinctly yellow.

“These are cheap,” Zoran said. “Two dollars a pound—and you get what you pay for.” He waved his hand in front of his nose. “Wow, they stink!”

Takumi laughed, and nodded.

“You can’t do anything,” Zoran said, “until the scales are off. Good luck!”

Good luck?
That was it? Kate stared at the enormous fish, and made the mistake of breathing through her nose. One of Kate’s classmates started sawing sideways, cutting off scales. The surface of the fish was curved so steeply that he could slice only one narrow section off at a time.

He stepped aside to let Kate try. She used her willow-leaf blade, but she had trouble getting it to go where she wanted it. The knife had dulled since yesterday. She pushed too hard and cut into flesh. She recoiled and stepped away, leaving a gash. Skinning such a big creature seemed more like skinning a person than a fish. Her classmate kept sawing. It took fifteen minutes just to complete one side. Kate watched.

“What are scales for?” she asked.

It was a good question.

Hundreds of millions of years ago, ocean worms burrowed in the mud for safety, but when they evolved toward fishdom they began to swim out in the open. They developed body armor for protection. The earliest fishes were called placoderms, from the Greek for “plate skin,” and they had big bony plates on their heads and necks.

The problem with armor plating is that it’s cumbersome. Scales evolved as a less protective but more liberating compromise. What the fish lost in safety they gained several times over in speed and agility. Scales are so useful that they appear all over in nature. The bodies of snakes are covered in scales. Sharks evolved their own version of scales separately from fish. So did insects, for use on their wings.

Some fish have unusual scales, or none at all, or they lose or gain scales depending on their life stage. These fish are generally off-limits to kosher eaters. According to the Torah, for example, eels are not kosher. Some rabbis consider swordfish not to be kosher because they lose their scales at a young age, in order to swim as fast as possible.

Zoran watched the students slicing scales off the yellowtail with their hand-forged blades. It was laborious work.

“Can you believe it’s 2005,” Zoran said, “and we’re still using this technology?”

He walked to the sink and came back with a steel scouring pad.

“This isn’t the Japanese way,” Zoran said, “but you can actually use this. Most restaurants that sell a lot of
hamachi,
they don’t have time, so they use this.” He looked at the pad in his hands. “It works.” Then he put it away. Zoran’s students did things the Japanese way.

Zoran surveyed the room and put his hands on his hips. “Oooh, I am
not
looking forward to taking the guts out. It’s going to smell.” He turned to Kate. “Come on, Kate, I haven’t seen you doing any.”

Kate moved tentatively toward the big yellowtail. She sawed across the surface again. She progressed 2 inches with her dull knife, then cut too deeply again and exposed flesh. She glanced up but Zoran had left the room. One of her classmates stepped in to bring the scaling line back to the surface. She tried again. This time she progressed 4 inches and stopped. She turned to the student next to her.

“Your turn,” she said.

Other students weren’t faring much better on the other fish. It looked like a burn victim.

Zoran reappeared with a Magic Marker.

“Look out, fish. Tattoo time!” He drew a dotted line behind the head, indicating the best path for decapitating the beast. He stepped out of the way. Kate’s classmate sawed down into the neck along the line, opening a deep gash. He turned to Kate. “Want to take a peek? Put your hand inside?”

In spite of herself, Kate peered into the gash. Her hand flew to her mouth. She pulled away. Her classmate kept sawing, making crunching sounds. Kate shook her head.

“It’s the cracking into the bones that gets me,” she said.

He couldn’t get the knife all the way through the thick spine. He gave up and cut along the belly. Bloated organs popped out like salamis. A sack of eggs slid into view, encased in a net of purple veins. The stench was overpowering.

Kate grabbed her nose. “Dis-
gust
-ing!”

Zoran laughed.

Kate’s classmate ran his fingers delicately along the guts, trying to determine the best way to remove them. Zoran butted in and simply ripped the organs out in handfuls and dumped them in the trash, spattering blood and globs of tissue all over the cutting board.

Now it was time to fillet. A large tubular fish like a yellowtail requires a more complex fillet plan than the “three-piece breakdown.”

With a fillet knife, Zoran traced long incisions around the edges of the fish, then deepened the cuts. He removed an entire side of the fish. Then, he divided it lengthwise with two new incisions on either side of the pin bones.

Zoran had produced two long blocks of flesh, roughly triangular in cross section and tapered at the tail end. Each long block contained about a quarter of the fish’s muscle mass. A busy sushi bar might go through one or two of these blocks a day.

This fillet plan was called
go-mai oroshi,
or the “five-piece breakdown.” It produced four quarters of meat, plus the carcass. The students tried their hand at filleting the other side, and then the other fish. When they had finished, Zoran grabbed one of the carcasses and dangled it over the trash can by its tail.