BUENOS AIRES, May 13 (Reuters) - The once-mighty but now cash-strapped Argentine soy crusher Vicentin said on Thursday it is starting talks to sell a majority stake to export firms Viterra, Molinos Agro and Argentine cooperative ACA.

Argentina is the world's No. 1 supplier of soymeal feed, used to fatten hogs and poultry from Europe to Southeast Asia. And family-owned Vicentin was the country's top exporter of soy byproducts before falling into bankruptcy in 2019.

"A majority group of Vicentin shareholders have accepted a non-binding expression of interest presented by three companies, with extensive experience in the industry, to evaluate the possibility of acquiring a majority stake," Vicentin said in a statement.

It added that the three parties had jointly expressed their interest in a possible acquisition.

Last year the government proposed taking the company over, but dropped the plan after an outcry from the local farm sector.

The purchase by Viterra, ACA and Molinos would involve months of due diligence with a deal needing approval by shareholders, Vicentin's bankruptcy judge and the company's creditors. When it ran out of cash, Vicentin left farmers and banks holding more than $1 billion in bad debts.

Creditors accused Vicentin of having used credits destined for the purchase of grains to finance other businesses. Vicentin denies any wrongdoing.

Viterra, a unit of Glencore Agriculture, owns 67% of crushing plant Renova. Located on the banks of the Parana River, near the Argentine grains port hub of Rosario, Renova is one of the biggest soymeal and soyoil manufacturing facilities in the world. The rest of the Renova plant is owned by Vicentin.

The other major asset Vicentin is selling is its San Lorenzo plant, which has a crushing capacity of 4.5 million tonnes of soybeans per year.

(Reporting by Hugh Bronstein; Editing by Leslie Adler, Alistair Bell and Richard Chang)