Oliver, who is paid £1.2m a year to front Sainsbury's advertising, said he was shocked when the supermarket's bosses refused his invitation to debate the way battery-farmed chickens are treated.
Oliver said: "I am really upset. The question is why didn't they come. What is there to hide? It is shocking that the people I work for didn't turn up on the day. I don't know why."
His comments have been widely reported, and featured on the Daily Mirror's front page today.
In the documentary, to be screened on Channel 4 on Friday, Oliver reveals that supermarkets pay farmers as little as 3p per bird.
The celebrity chef also asked bosses of Tesco, Asda and Morrisons to take part in the debate but all failed to show up.
A spokesperson for Sainsbury's said that the supermarket did participate in the making of the show, because its head of branding gave a full interview to Oliver, thereby making "a significant contribution to the show".
Oliver has appeared in more than 100 Sainsbury's ads over the past seven years. The latest of which was its Christmas campaign, by Abbott Mead Vickers BBDO, featuring Oliver visiting the food elves and offering tips on making Christmas food.
Oliver's contract with Sainsbury's is up for renewal in April, but he was expected to continue until 2009.
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