Official announcements have confirmed that Bright Food Group's bid to takeover CSR's sugar and renewable energy business, a deal which valued the unit at $1.5 Billion, has been formally rejected by the giant American firm.

On the news, CSR shares climbed by 1.5%, to trade at $1.975.

As confirmed by CSR in a statement to the Australian Securities Exchange, the company said that while it had seriously considered the Chinese group's offer, it would still prefer to go ahead with the planned de-merger for its sugar and energy division.

"CSR remains focused on maximizing shareholder value....(The) Board is of the opinion that the demerger is in the best interests of shareholders", the company said.

Experts, however, feel that this could just be a move in order to attract bids from larger overseas food companies like Brazil's Consan, Bunge and Cargill.

"(CSR's) statement is a tactic which, rather than discourage buyers, will cause them to be more forthright in putting forward both a stronger offer and a more formal offer", said White Funds Management portfolio manager Angus Gluskie.