At IMP Foods, ice is everywhere. As fish get moved, unpacked, checked, and repackaged, ice is involved every step of the way. You see ice and you hear ice—the crash of ice chips dumped on metal surfaces, the sloshing of slush, the soft noises made by shaved ice getting shoved around.
HOW FRESH IS YOUR FISH?
Left: A fresh three-foot-long king salmon. Middle: A cloudy eye
(above) is a sign of deterioration; a clear eye (below) is a sign
of freshness. Right: A thin film of mucus contributes to the
glimmer and sheen of a fresh fish.
We end the morning in the fish market’s kitchen, where it’s warm. Sakata has good news. He has located an ayu.
The fish, though flown in from Japan, is still so firm, clear-eyed, and gleaming fresh, it appears lacquered. “It looks just caught,” says McGee. “Its mucus layer is completely intact. Let’s see if I can get the gills to open up a little bit,” he says, gently lifting the gill flap. “The gills are often the first part of a fish to go. Their red turns brown with oxidation. And since gills are full of bacteria, because that’s where the water is filtered, they can generate unpleasant aromas. So let’s take a sniff.”
He puts his nose to the gills, which are a healthy bright red.
“Ah, I think I smell the melon!” he exclaims. “Can you smell it? I’ve been reading about this fish for years, in the abstract, because I’ve never seen it in a market,” he says in a rush. “In Japan, they’ve analyzed the aroma, because that’s what people say they value most about this fish, and they’ve found some of its compounds are exactly the compounds you find in melons and cucumbers.”
“He knows more about this fish than me,” Sakata says.
“That’s what’s so cool,” says McGee. “Once somebody points out to you that this fish smells like watermelon, all of a sudden there’s another dimension to the experience of eating it.”
Which we do then and there—the fish is simply sprinkled with sea salt and grilled whole. Glenn Sakata splits the fish open like a book, and we go at its mild, surprisingly soft white flesh with chopsticks, enjoying every last sweet morsel. Ayu, the sweetfish. “Who could ask for anything more?” says Harold McGee.
On Food and Cooking: The Science and Lore of the Kitchen
An excerpt from the newly revised book by Harold McGee
Copyright 1984, 2004.
To be published by Scribner, a division of Simon & Schuster.
Harold McGee proudly displays a
king salmon while visiting IMP
Foods in San Mateo, California.
“One of the great things about
living in northern California is
there’s a lot of local king salmon,”
McGee says.
People in many parts of the world enjoy eating ocean fish and shellfish raw. Unlike meats, fish have the advantage of relatively tender muscle and a naturally savory taste, and are easier and more interesting to eat raw. They offer the experience of a kind of primal freshness. The cook may simply provide a few accompanying ingredients with complementary flavors and textures, or firm the fish’s texture by means of light acidification (ceviche), salting (poke), or both (anchovies briefly cured in salt and lemon juice). And raw preparations don’t require the use of fuel, which is often scarce on islands and coastlines.
Probably the commonest form of raw fish is sushi, whose popularity spread remarkably in the late 20th century from its home in Japan. The original sushi seems to have been the fermented preparation narezushi; sushi means “salted” and now applies more to the flavored rice, not the fish. (The familiar bite-sized morsels of raw fish and lightly salted and acidified rice are nigiri sushi, meaning “grasped” or “squeezed,” since the rice portion is usually molded by hand. The mass-produced version of sushi found in supermarkets is formed by industrial robots.)
Many cultures from the Arctic to the tropics have recruited microbes to grow on fish and transform their texture and flavor. But the world center of fish fermentation is eastern Asia, where it has served two important purposes: to preserve and put to use the large numbers of small fish that inhabit the coastal and inland waters; and to provide a concentrated source of appetite-stimulating flavors—above all the savory monosodium glutamate and other amino acids—for a diet dominated by bland rice.
Fish fermentation apparently arose several thousand years ago in the freshwaters of southwest China and the Mekong River region. It then spread to the coastal deltas and was applied to ocean fish. Two broadly different techniques evolved: simply salting a mass of small fish or fish parts and allowing it to ferment; and salting larger fish lightly, then embedding them in a fermenting mass of rice or other grains, vegetables, or fruits. In the simple fermentation, the proportion of salt is usually enough by itself to preserve the fish from spoilage, and bacteria are important mainly as flavor modifiers. But in the mixed fermentation, a smaller dose of salt preserves the fish for just a few weeks while the plant-based ingredients feed the same microbes that sour milk or turn grape juice into wine. The fish is then preserved by the microbes’ acids or alcohol, and flavored by the many byproducts of their growth.
Of the many Asian fermentations that mix fish and grains, one of the most influential has been the Japanese narezushi, the original form of modern sushi. The best-known version is funa-zushi, made with rice and goldfish carp (Carassius auratus) from Lake Biwa, north of Kyoto. Various bacteria consume the rice carbohydrates and produce a range of organic acids that protect against spoilage, soften the head and backbone, and contribute to the characteristic tart and rich flavor, which has vinegary, buttery, and cheesy notes. In modern sushi, made with pristinely fresh raw fish, the tartness of narezushi survives through the addition of vinegar to the rice.
