Read The Story of Sushi Online
Authors: Trevor Corson
T
he next morning, Kate was on rice duty. She arrived at school early. After half an hour, on her eighth rinse, the rinse water was still cloudy. She worked her hands through the frigid water, mixing and rubbing the rice. She lifted the heavy bowl and poured the water out again. Her hands were turning numb.
This is going to give me arthritis,
Kate thought. Sushi apprentices in Japan did this every day for two years before they were even allowed to touch fish? Maybe the California Sushi Academy wasn’t so bad. Kate put the rice on to cook just as Zoran took roll. She rushed to the classroom.
“Today, salmon,” Zoran was saying. “In Japanese it’s called
sake,
or
shake
to distinguish it from sake.” In Japanese the two words are written with different characters—one for salmon, another for rice liquor—but they are pronounced the same. Sushi chefs had fiddled a little with the language to avoid confusing themselves behind the sushi bar.
“Now,” he went on, “I have some news for you. The Japanese don’t usually use salmon for sushi. When I was in Tokyo with Toshi, some tourists asked a sushi chef for salmon, and he stood looking at them as if they were crazy. You know why?”
No one did.
“Parasites. Salmon are susceptible to parasites.”
In fact, they’re worse than mackerel. A study in the 1980s found anisakis larvae in every one of the fifty wild salmon the researchers took from Puget Sound. And because salmon swim in freshwater as well as the ocean, they can carry the larvae of tapeworms, too. In 1981, the Centers for Disease Control issued a warning after a tapeworm outbreak in California was traced to salmon sushi. Tapeworms are a primary reason why traditional sushi chefs seldom serve freshwater fish raw. Once a tapeworm takes up residence in a human, it can grow to a length of several feet. A museum in Tokyo dedicated to parasites houses a tapeworm that was extracted from a man who’d eaten a raw trout, a freshwater relative of salmon. The worm in the museum is nearly 30 feet long.
Unlike bacteria, parasites are complex, multi-celled organisms. Cooking will kill them, but so will cold enough temperatures. The solution for raw salmon, Zoran explained, was to freeze the fish in the restaurant’s industrial freezer. Some people consider unfrozen fish a requirement for high-quality sushi, but unfrozen salmon are a very bad idea. The chefs at Hama Hermosa froze their salmon for a minimum of seventy-two hours before thawing and serving it. Most sushi chefs are less strict about freezing mackerel because they salt and vinegar it.
The lower the temperature, the more quickly the parasites die. In the United States, the FDA recommends that distributors or restaurants freeze
all
fish that will be served raw for eighteen hours at -31°F, a temperature that only a high-powered blast freezer can achieve. At the more conventional temperature of -4°F, the FDA points out that the fish has to be kept frozen for an entire week to destroy parasites. Most home freezers don’t go much below 0°F.
The FDA simply issues recommendations. Individual states must implement their own regulations, and many have. As of the summer of 2006, California still had no statewide codes to enforce fish freezing. Fish suppliers are supposed to track any health risks, and local health inspectors do visit sushi restaurants regularly and hand out scorecards that must be posted at the entrance. People
do not generally get sick from eating salmon sushi. Nevertheless the “Kids Page” on the California Food and Drug Web site puts it this way: Eating sushi “may not be very safe for you.”
Salmon belong to one of the oldest families of fish in existence. Along with freshwater trout, salmon go back 100 million years.
There is evidence that the group of creatures we generally think of as fish did not first evolve in the ocean. Like salmon and trout, all fish may have their origins in freshwater. Between about 350 and 400 million years ago the earth exploded with new life forms. In the ocean, the wormlike fishes evolved into new species. Some of these moved into freshwater. There they developed skeletons made of hard bone. Subsequently, many of them returned to the ocean with their new equipment and recolonized the sea. These may well have been the ancestors of the ocean fish we know today. Many others stayed behind. Forty percent of all species of bony fish still live in freshwater.
Salmon live in both worlds. Salmon are born in freshwater, spend from one to five years in the sea, and return to freshwater and fight their way up raging rivers to spawn in the streams of their birth. Why go to such trouble?
In the relatively cold climates at higher latitudes, where salmon live, the ocean provides a richer buffet of nourishing food than freshwater. But freshwater streams are safer places for babies to grow up. By taking advantage of both environments, salmon eat well, and their eggs and young have high survival rates.
Salmon smell their way back to their birthplace. As they begin their trek upstream from the ocean, they eat the last meal of their lives. From then on they will survive by burning their own fat and digesting the proteins in their own muscles.
As they head upriver they also undergo astonishing anatomical changes, not unlike Dr. David Banner’s transforming into the Incredible Hulk. At sea, salmon are handsome and respectable-looking silver fish. By the time they return to their home streams, depending on the species, they have developed green heads, bright-red skin, bizarre color patterns, beaked jaws with nasty teeth, and hunched backs.
These monstrous fish flail around in streams that are much too small for them, the males ramming and biting each other and the females attacking everything that moves. The females turn on their sides and whack their tails into the gravel, digging depressions to lay their eggs. The toughest males duke it out for the right to spray sperm on the eggs. The violent orgy ends in death for all the salmon.
Meanwhile, bears swipe salmon from the water by the fistful. Bears are finicky sashimi eaters. They eat only a few bites of each salmon before tossing it aside and ambling back into the water to catch another. They leave lacerated salmon strewn across the forest floor.
At a sushi bar this behavior would merit eviction, but in a forest it’s welcome. Plants living near salmon streams contain large amounts of nourishing nitrogen, and tests have shown that up to 70 percent of it came from the ocean, via salmon. Tree growth near salmon streams is three times greater than near comparable streams without salmon.
“Now, to farming,” Zoran said. He explained that most salmon served in sushi is farmed salmon.
Industrial pollution began killing off wild salmon in major rivers around the world as early as the nineteenth century. In England, the last salmon in the Thames were caught in 1833. The construction of dams destroyed many salmon runs as well.
Norway pioneered the farming of salmon in the 1970s, followed by Scotland. The Europeans expanded salmon farming into Canada, the United States, and Chile. Today, a handful of multinational corporations control much of the industry, and farmed salmon account for half of all salmon sold. Fishermen who catch high-quality wild salmon have trouble staying in business because cheap farmed salmon glut the markets.
Salmon farming has made salmon more plentiful, but in a sense it has also created a new kind of fish. And for sushi, most Americans prefer this new kind of fish. The reason is simple. As Zoran liked to put it to his customers at the sushi bar, “Farmed salmon don’t work for a living.”
Wild salmon work hard. In the wilds of the Pacific Northwest and Alaska, free-swimming salmon continue to throw themselves year after year into the grueling marathons that return them to the streams of their birth. To fortify themselves for the trip, they hunt a variety of wild prey, including miniature shrimp called krill.
Krill eat algae. As a result, they are full of a photosynthetic pigment called astaxathin, similar to the carotenoid that makes carrots orange. Many kinds of fish absorb this pigment, giving their skin a red tint, but only salmon absorb it into their flesh, which is why salmon meat has a unique, orangey pink color. Flamingos eat small crustaceans similar to krill and are pink for the same reason.
To a sushi chef, salmon doesn’t qualify as a red fish. It’s a white fish because the color doesn’t belong to the fish. Salmon farming operations must add pigment to the feed or their farmed salmon will turn out white and disappoint the consumer.
In the wild, salmon gain flavor as well as color from their prey. As they hunt, they swim hundreds of miles to return to the mouths of their native rivers. By the time the fish are caught, they’re well-exercised.
By contrast, farmed salmon are couch potatoes. They mill around in pens, gorging themselves on rich, oily fish meal. Companies manufacture the meal by grinding up fatty fish such as mackerel, herring, sardines, and anchovies in giant industrial blenders.
Sometimes Zoran would serve his customers two different
nigiri,
one topped with wild salmon, one topped with farmed salmon. The flesh of the wild fish was usually dark, pungent, and—depending on when and where it had been caught—relatively lean. It didn’t melt in your mouth; you had to chew it. The taste was strong and the flesh had texture.
The farmed fish was soft, pale, and striped with thick streaks of fat. And, by comparison, it tasted bland.
The recent popularity of fatty tuna in sushi has led people to value a rich, fatty, melt-in-your-mouth sensation over flavor and texture. The aquaculture companies have been happy to oblige. Fat, lazy salmon are what they do best.
Unfortunately, lack of flavor and texture isn’t the only downside. All that fat in farmed salmon is loaded with around seven times the PCBs—polychlorinated biphenyls, likely a cause of can
cer—that wild salmon contain. Since 3 pounds of smaller fish are necessary to produce 1 pound of salmon, the salmon “bio-accumulate” more of the toxic PCBs from eating the smaller fish than they would from eating krill directly.
Many farming operations also pump their salmon full of antibiotics, as disease can run rampant in the crowded pens. On the other hand, farmed salmon are less likely to transmit parasites to humans.
Traditionally, the favorite sushi toppings in Japan were lean, firm fish like snapper and flounder. In the past, Japanese fishmongers sliced off the fatty portions of their fish and tossed them on the floor for their cats. When an entire fish had a high fat content—mackerel, for example—they salted it and marinated it with vinegar to cut through the oil, just as Kate and her classmates had learned to do. But after Western food became popular in Japan, the Japanese started to include the fatty cuts of fish in sushi, too. That said, Japanese chefs tend to consider farmed fish inferior.
In the United States, the preference of diners for bland fatty salmon has been a bonanza not just for aquaculture but for sushi chefs as well.
“If you want to open a restaurant,” Zoran said, “salmon is your moneymaker. Very cheap to buy.” He meant farmed salmon, of course. “You can make a lot of sushi from a big salmon fillet.
“Now,” Zoran said, “I have a problem. I ordered salmon with the head on, but I got salmon fillets. Sorry.”
No fish heads? Kate was not upset by this news. Zoran unwrapped a green cellophane package.
Most fish are either fairly thin or fairly plump. For example, a snapper is a tall, narrow fish, while a tuna is a wide, tubular fish. Both extremes cause complications when breaking fish down into
neta
blocks that can be sliced easily for sushi. But a salmon is just right—a relatively big fish, thick enough in cross section, but not round. So cutting salmon is simple—another reason sushi chefs like it.
Zoran laid his palm on the featureless orange slab of salmon
flesh and sliced off a rectangle the width of his hand. The resulting block was ready to be wrapped in plastic wrap and stored in the fish case at the sushi bar.
Zoran laid his palm on the fillet and cut off another large rectangle. “See, four finger wide.” He looked around at the students. “Got it?”
They nodded. Zoran distributed several fillets around the table and the students paired up. First, they felt the flesh for pin bones to extract with their tweezers. Bent over the stainless-steel table in their white coats, with their steel blades and instruments, they looked like surgeons.
Kate had crossed over to work with one of her classmates. He took his Western-style chef’s knife from his case and cut the fins off the fillet, then handed the knife to Kate.
Kate laid her palm on the fillet. It was slimy. She sawed through the flesh to create a hand-sized block. When the knife hit the skin on the underside of the fillet, it stopped cutting. She gave up and handed the knife back to her classmate.
He couldn’t get his knife to cut through the skin, either. Zoran noticed. He grabbed the knife and tested it on his thumbnail.
“Whose knife is this?” Zoran asked, looking at Kate.
“Mine,” the other student said.
Zoran stifled a laugh. “It’s not sharp!” He tapped the blade theatrically on the flesh of his palm. Kate winced, but the knife drew no blood. Zoran glared at the man and shook his head. “You
can’t cut fish
if your knife
isn’t sharp.
” He strode away.
Kate jogged back to her station and fetched one of the knives she hadn’t used since they’d been sharpened. It cut through the skin with one quick slice. They broke the rest of the fillet down into blocks and wrapped them in plastic wrap.
“Think about what flavors go well with salmon,” Zoran instructed them. “Because now I want you to come up with salmon sushi of your own. Your own style. Fusion is okay. Whatever you want.”
The students frowned.
“Come on!” Zoran yelled. “Let’s go. Salmon sushi, your style!”
Zoran burst into action. He squeezed out six quick salmon
nigiri
. He topped one with sesame seeds and an ultra-thin wedge of lemon. On another he sprinkled bonito flakes over a sliver of rinsed
white onion. Another he topped with a dash of teriyaki sauce, and another with creamy sesame dressing. The fifth he painted with sweet miso and egg yolk, then he seared it with a blowtorch. He peeled up the last slice of salmon and slipped half a perilla leaf between the fish and the rice.