ST. LOUIS (AP) — Post Holdings will spend $1.15 billion to bulk up its presence in the cereal aisle by buying the privately held MOM Brands Co., maker of Malt-O-Meal cereals.

Post said Monday it will pay $1.05 billion in cash and give MOM Brands owners nearly 2.5 million shares of stock for the acquisition, which is expected to be completed in the third quarter.

MOM Brands' product portfolio includes branded, ready-to-eat cereals as well as hot wheat and oatmeal products. Its cereals include Golden Puffs, Frosted Mini Spooners and Cinnamon Toasters, which are similar to cereals made by competitors but generally sold in bags at lower prices. The company is based in Lakeville, Minnesota.

The deal comes at a tough time for the cereal business, as more people are looking for breakfasts they can eat on the go or avoiding carbohydrates or gluten in favor of protein.

Post has been on acquisition spree lately to diversify, adding the PowerBar and Musashi nutrition brands, which it purchased from Nestle SA, and the peanut butter maker American Blanching Co.

Last June, it completed a $2.45 billion acquisition of fellow packaged food maker Michael Foods Inc.

Post Holdings Inc. plans to finance most of the MOM Brands deal and sell about $240 million in stock, subject to market conditions.

Post, which is based in St. Louis, also makes nutrition drinks and a variety of store-brand products including pasta. It said Monday that it expects about $1.07 billion in revenue for the fiscal quarter that ended Dec. 31.

That forecast matched Wall Street expectations, according to the data firm FactSet.

Shares of Post Holdings jumped more than 12 percent, or $5.16, to $46.62 in early afternoon trading while broader indexes were largely flat. Post Holdings shares had fallen about 23 percent over the past year, as of Friday's close.