E.coli inquiry will focus on quality
Health minister Brian Gibbons reassured Assembly members that "no stone would be left unturned" in any future investigation.
He said the Assembly government's investigation would be "open and transparent", but rejected opposition calls for an immediate public inquiry.
Former GP Dr Gibbons told AMs he believed the number of cases had peaked.
As TES Cymru went to press, the total stood at 144, spread across four LEAs. Five new schools have been struck, bringing the number affected to 37.
The outbreak started almost two weeks ago, with seven pupils affected at schools in two local authorities. Some parents have reacted angrily, and said schools should have been closed to contain the spread of the bacteria.
Some are considering legal action after their children were affected by the potentially fatal food poisoning.
Education and lifelong learning minister Jane Davidson came under fire from Assembly members for not supporting the closure of schools. In a debate this week, Leighton Andrews, AM for Rhondda, said those responsible should be held accountable. He said it was vital to look at the quality of inspection of food supply chains servicing schools.
He said schools and parents in his constituency were struggling to come to terms with the outbreak. Jenny Randerson, Lib Dem AM for Cardiff Central, said an inquiry must address how contracts are awarded for school-food supplies, especially meat.
Jonathan Morgan, Tory AM for south Wales central, said: "The authorities knew on the Sunday about the outbreak but parents still went to school on the Monday oblivious to the fact - they should have had the right not to send their children."
He said the role of school staff needed to be examined. Plaid leader Ieuan Wyn Jones said more locally-sourced food should be used in schools after the outbreak and "lessons learned".
The debate came as LEAs and schools became increasingly reluctant to divulge information under the threat of legal action. At least one of the four LEAs affected by the outbreak has instructed schools not to talk to the press.
School canteens were being ruled out as a source of the infection as early as last Tuesday. John Tudor and Son, a Bridgend meat suppliers named last week as a possible link to the outbreak, is still being investigated.
The four LEAs with E.coli cases - Caerphilly, Bridgend, Merthyr Tydfil and Rhondda Cynon Taf - are all members of a consortium, led by RCT, which bought supplies from John Tudor. A spokesman for Caerphilly council said it was satisfied all measures to ensure quality and value were being adhered to by the firm and the Bridgend environmental health authority.