The principal trial of those involved in the collapse of Parmalat, the Italian food and dairy giant, began in Parma yesterday, but without Calisto Tanzi, the group's 70-year-old founder, appearing in court.

Fifty-five defendants face charges of bankruptcy fraud, false accounting and criminal association. Mr Tanzi, his brother Giovanni and Fausto Tonna, the bankrupted company's former finance director, are among 24 former executives who face charges that carry a maximum 15 years in prison. All deny the charges against them.

The collapse of Parmalat in late 2003 cost 100,000 small shareholders their savings after 14 billion (£10.8 billion) - eight times the amount admitted previously - was found to be missing from the group's accounts.

The bankruptcy, dubbed “Europe's Enron”, has already given rise to a series of trials in Milan involving lesser defendants. They include Mr Tanzi's children, Francesca and Stefano, who held posts in Parmalat subsidiaries, including Parma football club and the Parmatours travel company.

Lawyers for Mr Tanzi, who turned a small family food firm in Parma into a global conglomerate, said that he had “assumed his responsibilities” and “offered his apologies”, but added that “all those who contributed to making savers the victims must be held accountable”. The lawyers said that Mr Tanzi would appear for later hearings even though his health was “precarious”.

Gianpiero Biancolella, one of the defence lawyers, said that Mr Tanzi was “at home, being a grandfather”. Under Italian law, defendants are not obliged to attend their trials. A three-year investigation and a year-long pre-trial hearing have generated six million pages of legal documents, so far.

In one of the parallel Milan trials, five foreign banks - Citigroup, Morgan Stanley, Bank of America, UBS and Deutsche Bank - are accused of share-price manipulation. Similar charges have been brought in another trial in Milan involving Italian banks and auditors. Mr Tanzi accuses the various banks of financing Parmalat while knowing that it was insolvent, a charge that they deny.

The trial, which merges five smaller trials into one “maxi trial”, is expected to last up to three years because of its complexity. Yesterday it was adjourned until May.

In addition to the prosecution's 250 witnesses, Mr Tanzi's defence lawyers have listed 35,000 small shareholders who they hope will testify that they were persuaded to buy bonds by “irresponsible” banks and not by the company.

At its height Parmalat employed 36,000 people in 30 countries. Parmalat milk and yoghurt products reappeared in Italian shops three years ago after it resumed dairy operations under Enrico Bondi, its new chief executive, who has recouped €1.3 billion from banks. Last year it made net profit of €673 million.

Notes on a scandal

December 2003: Hole in accounts found

January 2004: Auditors questioned; Carlo Tanzi arrested; lawsuit filed against Citigroup

March: Parmalat agrees loan deal

August: Parmalat sues UBS, Bank of America and Citigroup

October: Citigroup sues Italian Government

June 2005: Eleven Parmalat executives and lawyer convicted of market-rigging

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