PORTLAND — Alpenrose, a longtime Portland dairy and community institution, could be in jeopardy as family members face off in court over the future of the 128-year-old business.

Established in 1891 by Florian Cadonau, Alpenrose today produces a variety of conventional and organic dairy products such as fluid milk, cottage cheese and sour cream. The company also hosts numerous events at its 52-acre property, which includes three baseball fields, a velodrome track, 4-H Discovery Farm and “Dairyville,” a replica frontier town.

All that could disappear, according to a lawsuit filed March 4 in Multnomah County Circuit Court by Carl Cadonau III, Tracey Cadonau McKinnon and Cary Cadonau, the youngest generation of family owners and the great-great grandchildren of Florian Cadonau.

The siblings allege their aunts, Barbara Deeming and Anita Cadonau-Huseby, are working through a series of family trusts to sell Alpenrose to an unnamed third-party, which would immediately stop community activities on the land and close the dairy after one to two years.

If the sale goes through, the plaintiffs allege Deeming and Cadonau-Huseby intend to liquidate assets worth in excess of $35 million.

“Deeming and Huseby intend to destroy a legacy, community and an historical family business for their own material benefit,” the lawsuit states. The plaintiffs are suing to stop a sale, which they say violates the spirit of the Cadonau Legacy Plan and would impact more than 150 Alpenrose employees.

Calls and emails to Carl Cadonau III, who is vice president of operations at Alpenrose, were not returned. Barb Bradshaw, whose public relations agency represents Alpenrose, also did not return a call for comment.

Josh Thomas, a spokesman for the Oregon Dairy and Nutrition Council, said Alpenrose is part of a diverse industry in Oregon that includes 210 dairy farms and more than 30 processors statewide.

Just last year, Portland lost another dairy company, Sunshine Dairy, which sold part of its operations to Alpenrose and part to Kite Hill, which makes plant-based, non-dairy cheese and yogurt.

Thomas said there are three primary concerns with the potential loss of any dairy processor, including the impact on jobs, industry and community.

“It’s just another area where we want to see that processing capacity stay in Oregon, along with the economic benefits, brands and products those companies provide,” Thomas said.

Dairy products support 12,000 jobs in Oregon, with an economic impact of $2.7 billion, according to the Dairy and Nutrition Council.

While Alpenrose no longer milks its own cows, Thomas said the company does buy raw milk from other local farmers. Fewer processors means fewer options for farms, which can depress prices.

Whenever a processor goes out of business, it takes time for the market to find equilibrium, Thomas said — as happened with the closing of Sunshine Dairy. The question, Thomas said, is how long farmers can bridge the gap until they find another market, especially with milk prices already at historic lows.

“For any farms selling to any specific processor, that would be a concern,” he said.

Then there is the impact on community. As a fixture of the Portland scene, Alpenrose has played host to the Little League Softball World Series for more than 25 years, and for more than 60 years the dairy has held an annual Easter egg hunt and Christmas celebration at Dairyville.

“They are part of a diverse dairy community that is really something we celebrate here in Oregon,” Thomas said.

Lisbeth Goddik, a dairy processing specialist at Oregon State University Extension Service, said that diversity is unique in Oregon, with so many mid-size dairy processors such as Alpenrose in Portland, Umpqua Dairy in Roseburg, Lochmead Dairy near Eugene and Eberhard’s Dairy in Redmond.

The trend in other states is moving toward fewer, larger specialty processors, Goddik said. Alpenrose cannot compete in terms of mass production and price, so it focuses more on process and product quality to earn a loyal customer base.

“It’s an attention to detail, making products the more authentic way, and certainly having good quality raw milk that you turn into dairy product very quickly,” she said.

Goddik currently serves as interim head of the Department of Food Science and Technology at OSU. She said the university places a lot of students in the dairy industry every year, and as more mid-size processors close, those jobs are shifted out of state.

Goddik said Alpenrose is a great company, and she hopes it can continue operating.

“I would just hate for Oregon to lose them,” she said. “We would gain nothing, and lose a lot.”