In the pint-size kitchen of his San Francisco home, chef, restaurateur and cookbook author Carlo Middione hunches over a counter, methodically rolling veal meatballs as tiny as necklace beads to add to a pot of simmering chicken broth.

At the dining table, he ladles the soup into bowls, adding a shower of freshly grated Parmigiano to each. Then he digs in, lifting a spoonful to his mouth.

The soup, a favorite recipe of his mother's, is one he's made countless times. But these days, he can no longer taste it. The distinctive flavors of garlic, parsley, sage and rosemary in the meatballs are elusive. The savoriness of the broth is undetectable. If he concentrates, he can he pick up a trace of salt. That's it.

Three years ago, Middione's palate went from Technicolor to black. After a car accident in which his small sedan was rear-ended by a Toyota Tundra, Middione lost his ability to smell and taste.

For a man whose senses were once so acute he could sniff a vinaigrette and tell if it was balanced, or determine whether a pot of boiling pasta water was salted just by smelling it, the loss was devastating.

It led to him closing his 29-year-old Fillmore Street restaurant, Vivande Porta Via, on New Year's Eve 2009, and to relearning how to cook and eat when the senses he once relied on could no longer be fully trusted.

"When I see a strawberry now, I can verbally describe what it tastes like," he says. "But if I tasted it, I might not taste anything. I get phantom tastes and smells now. Some people think that's a good sign. It's like if the phone rings, and it turns out to be a wrong number. At least you know the phone is working."

Middione has some company in the professional chef world. Most notably, chef Grant Achatz of Alinea in Chicago lost his sense of taste after undergoing chemotherapy for tongue cancer. And Kirk Webber, chef-owner of Cafe Kati in San Francisco, lost his sense of taste after suffering two concussions in a mugging in 2003.

These chefs eventually regained their ability to taste, although they are considerably younger than Middione, who's in his mid-70s.

When taste disappears, it's often because of the loss of the sense of smell, says Barb Stuckey, an executive at Mattson, a large food-development firm in Foster City, who is writing a book on the subject that features Middione. Anyone who's ever tried to figure out the flavor of a jelly bean while chewing it with pinched nostrils knows that all too well.

Loss of smell, and thus taste, also occurs naturally with age, but Middione suffered head trauma. The impact not only cracked Middione's sternum, ribs and several teeth, but he says it also jostled his brain so severely that it sheared the neurons that connect to his olfactory nerve, which is instrumental in the sense of smell.

Generally, those neurons regrow and reconnect. Sometimes they reconnect perfectly; sometimes they don't ever rejoin; and other times they form wrong connections that result in phantom smells.

On painkillers for a month and able to eat only chicken broth and soda crackers, it took awhile for Middione to realize that something was wrong. But when he started to eat normally again, nothing tasted right.

Then he started experiencing faux odors as foul as rotting meat.

"I used to love coldwater mussels. But I had to leave the restaurant when we were cooking them," he says. "That lasted for two years. At one point, I couldn't take the smell of chicken stock, either. Or chocolate. Or salmon."

Finally, after cooking a batch of minestrone soup so salty it had to be thrown out, he decided to close his restaurant.

It was crushing for Middione, who is of Sicilian heritage and the son of a chef, but the only one of his 12 siblings to cook professionally.

He hasn't worked since closing the restaurant, but he doesn't want to retire. He's considering restaurant consulting or even becoming a prep cook. He'll be the first to tell you that he can still skin a fish or bone a chicken faster than almost anyone.

And he's still passionate about cooking, preparing almost all the meals at home for himself and Lisa, his wife of 44 years and his chief taster.

"Texture was always important, but now even more so," he says. "I like the crunch of lettuce and the creaminess of beans. That gives me pleasure now."

Inside: Review of the Gold Mirror, plus more on Michelin in The Inside Scoop. E3

Sunday: Timothy Mondavi's next act. Food & Wine