Shares in US food group Ralcorp Holdings tumbled today (21 June) after the owner of Post cereals said its third-quarter profits would be lower than a year earlier.

Ralcorp shares were down by 5.8% in early trading after the company forecast third-quarter diluted earnings per share of US$1.00 compared to the $1.31 it earned a year ago.

The company, which announced three acquisitions on a day of significant expansion for the business, including a $1.2bn deal for American Italian Pasta Co., blamed lower returns from promoting its Post cereal brands.

Ralcorp said competitive activity from other US cereal brands had weighed on its private-label cereal business within its Ralston Foods division.