According to Sky News, potential investors include HIG Europe, Sun European Partners, and PAI Partners.
French buy-out firm PAI Partners owns United Biscuits, alongside US private equity group Blackstone, after it bought the company back in 2006 for £1.7bn.
Last month, parent company Premier Foods bowed down to rumours, and confirmed that it had appointed Ondra Partners, a private equity group, to look at its options for investment.
The company has spent £28m on restructuring its bread business this year after closing two mills and three bakeries, and losing several contracts.
Last month Premier reported sales were down in its bread business by 1.5% year-on-year, for the three months to 30 September 2013.