The deal, which includes the sale of brands such as Hartley's jams and spreads and Sun-Pat peanut butter, sent shares of Hain Celestial up 10% in extended trading.
The deal, expected to close by the end of October, would help the company supply packaged groceries that do not require cold storage to major retailers in the U.K. such as Sainsbury's, Tesco and Marks & Spencer.
The U.S. organic products company, known for its Earth's Best and Celestial Seasonings Brands, expects sales from the Premier Foods business during the eight-month period from closing to June 30 to be about $180 million.
The transaction will consist of 170 million pounds in cash and 30 million pounds in Hain Celestial shares.
The Premier Foods brands that Hain will acquire generated over $250 million in sales in its last fiscal year.
Premier Foods has been trying to reduce its debt pile and meet bankers' sell-off demands after the company was weighed down by the acquisition of Hovis and Mr Kipling group RHM in March 2007.
Separately, the company reported a fourth-quarter profit that beat Wall Street estimates on the back of higher demand for its products in the U.S., and forecast strong full-year earnings.