In preparation for oshogatsu – the new year, traditionally the most important holiday for Japanese American families, with abundant feasting and large family gatherings – 79-year-old Lillian Matsuoka of Walnut Grove has been cooking.

And cooking. And cooking.

She's made ozoni, the special soup that's sipped first thing on New Year's Day to ensure good luck, good fortune and good health in the coming year; a half-dozen varieties of sushi; seaweed salad; cucumber salad with miso and ground sesame seeds; chicken teriyaki – and more.

"I know a lot of people don't do all this anymore," said Matsuoka. "I'm ready to retire from New Year's.

"I keep telling my kids to learn the food preparation, so then I won't have to cook. And every year, they tell me, 'No, you have to do it.' "

As her generation – the Nisei, the second generation in this country – fades away, the centuries-old tradition of the Japanese new year is shifting for the Japanese American community.

In many ways, the change is an inevitable part of the American story, a transition similar to those that other immigrant communities have undergone through the decades. Simply put, experts say, the further removed generations are from the immigrants who first came to America, the less likely they are to keep alive the cultural traditions of the immigrants' home country.

Life gets busier. The threads of connection are lost.

"With everybody working, you don't spend that much time cooking with the mother or the grandmother," said 45-year-old Tallie Matsuoka Pagano, Lillian's daughter, who lives in Walnut Grove and works for Sacramento County.

"And with mixed marriages, you don't have both sides of the culture in the family at the same time. We're more Americanized and more mixed. The culture isn't there anymore."

Studies show that more than 60 percent of American-born people of Japanese descent intermarry with people from other ethnic backgrounds.

Largely on the strength of their multiracial offspring, the population of people identifying themselves as Japanese American increased by more than 155,000 in the decade ending in 2010, according to U.S. census figures. But the number of people claiming Japanese American heritage alone dropped by more than 33,000 during that period.

"I have some families who are six generations deep here," said the Rev. Bob Oshita of the Buddhist Church of Sacramento. "I don't know how long the traditions will continue. As we become fifth and sixth generation, things will change."

As 2011 wound to a close, Oto's Marketplace in Sacramento was jammed with customers carefully selecting packages of mochi and ordering platters of sashimi and sushi for New Year's feasts.

Store manager Russell Oto said the market has adapted to the demands of baby boomers – the Sansei, children of the Nisei – while still accommodating his strongest customer base, the Nisei themselves.

"The traditional foods are being weeded out," he said. "The older generation makes everything from scratch for New Year's, but now the Nisei aren't cooking much anymore. The younger ones, everything's to go."

Strictly speaking, the oshogatsu celebration is Buddhist in origin and involves ringing out the 108 sins of the old year at church, then welcoming the new year with ozoni and sake at another service the next morning.

Then comes the visiting.

"Very much a part of Japanese culture is visiting others, going house to house," said Oshita. "You just stop and toast the new year and wish each other well and have New Year's food."

Some Nisei, such as Kiyo Sato-Nunnelly, 88, who lives in Rosemont, dropped most of the traditions of oshogatsu many decades ago.

"You know, it is work," she said. "And it's all women's work. The women cook for weeks, and then they stay home while the men go out drinking and eating. It's exhausting."

Some Japanese American families instead meet for dinner in restaurants, keeping alive the importance of gathering the generations together but discarding the days of intense cooking and preparation ahead of time.

These days, Tallie Pagano and her sisters help their mother make the New Year's sushi, learning as they go, because they want to keep the tradition alive.

"I like the tradition of it," Pagano said. "There's a lot of history and a lot of good memories for me. It's time for family to get together.

"We do a whole day of it, and it's always good memories."

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