Image source: The Motley Fool. 

What: Shares of Flowers Foods, Inc. (FLO 1.38%) were taking a dive today after the owner of brands including Wonder Bread and TastyKake said second-quarter profit fell, and it lowered its full-year guidance. As of 10:44 a.m. EDT, the stock was down 10.7%.

So what: Net income fell 1.2% in the quarter, but adjusted earnings per share increased by a penny to $0.26, matching estimates. On the top line, sales grew 5.2% to $935 million, though that was short of expectations at $949 million.

CEO Allen Shiver credited the recent acquisitions of Dave's Killer Bread and Alpine Valley Bread for driving growth in the quarter, but said sales declined in core markets "due to competitive pressures." As a sign of the company's struggles, it introduced Project Centennial, a comprehensive operational review of the business to streamline costs and grow revenues.

Now what: Like other legacy food makers, Flowers has struggled with the rise of organic and alternative brands, though its recent acquisitions give it a stake in the growing segment. Looking ahead, the company lowered its guidance for the full year. It now sees revenue of $3.93 billion to $3.986 billion, representing growth of 4% to 5.5%, down from a prior range of $3.986 billion to $4.08 billion. Projected EPS is now at $0.90 to $0.95, compared to $0.92 a year ago and earlier guidance of $1.00 to $1.06.

Shiver said he was confident that the company would be able to increase shareholder value through Project Centennial, but a return to growth won't come without challenges. Shares are now at their lowest point since 2012.