The headline of PepsiCo's (NYSE: PEP) second-quarter earnings release reads: "PepsiCo Delivers Solid Financial Results for Second Quarter 2011."

Well, there you have it, right? If they say so, we should probably just assume everything is great and there's nothing to worry about. What's that you say? You'd still like to take a closer look? Oh, all right.

Voting with the sell button
Obviously Mr. Market didn't quite agree with PepsiCo's headline. Shares ended the day down 3.4% yesterday, suggesting that investors had a different idea of what "solid financial results" would have looked like.

For the second quarter, PepsiCo reported core earnings per share of $1.21. That was up 10% from the second quarter of last year and right in line with analysts' estimates. Excluding the purchase of Wimm-Bill-Dann, revenue was up 8% year over year, and total revenue of $16.8 billion topped analysts' estimates. Again excluding WBD, worldwide beverage volume increased 2%, while snacks volume climbed 4%.

Maybe those aren't knock-your-socks-off numbers, but so far, I'm with management -- this seems like a pretty solid quarter.

A-ha, I got it!
Investors tend to get much more excited over what a company is going to do as opposed to what it's already done. So what does PepsiCo's management see ahead? In a Frito-Lay-brand nutshell, it's not nearly as tasty as the second quarter.

PepsiCo Americas Beverages, which includes the challenging, but very important U.S. market, was not a highlight of the second quarter, and it doesn't sound like there's any quick fix there. Archrival Coca-Cola (NYSE: KO) has been kicking PepsiCo's butt, and both Coke and Diet Coke now occupy higher brand spots than PepsiCo's flagship cola. As I noted in Coke's earnings round-up, PepsiCo is hoping to make up some ground through a promotional push, but that'll cost the company money and there's no guarantee that it will pay off.

It also seems that PepsiCo underestimated the impact that continued commodity pressures would have on the bottom line. This was a key reason cited for the company lowering its 2011 earnings-growth outlook. It now expects that 2011 earnings will grow "high-single-digits" versus 2010 -- and that includes a 2% benefit from foreign exchange. That compares to previous guidance of 7% to 8% growth on a constant currency basis (that is, without the foreign exchange impact).

Investors in companies like Procter & Gamble (NYSE: PG), Clorox (NYSE: CLX), and Kimberly-Clark (NYSE: KMB) may want to take particular note of PepsiCo's commodity-price struggles. These companies have yet to report and if they didn't adequately work cost pressures into their estimates, they could be telling a similar story in their earnings releases.

Please, keep selling PepsiCo!
Personally, I'd love to see the market continue to sell off PepsiCo's stock. I don't own any in my own portfolio, but if it got much cheaper that could very easily change.

The market is manic-depressive -- we Fools know that. Just last quarter, investors were bidding up shares of PepsiCo because things looked a bit better than they had expected. Now they're selling because things look worse than they thought.

PepsiCo isn't a day-trading stock -- it's the kind of stock that you can own for years and not lose sleep. Yes, there are some challenges -- particularly North America beverages and the eternal struggle with Coke -- but I don't think long-term-oriented investors should be tearing their hair out over this report.

The Motley Fool owns shares of PepsiCo, Clorox, and Coca-Cola. Motley Fool newsletter services have recommended buying shares of PepsiCo, Coca-Cola, Clorox, Kimberly-Clark, and Procter & Gamble. Motley Fool newsletter services have also recommended creating a diagonal call position in PepsiCo. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors.

Fool contributor Matt Koppenheffer does not have a financial interest in any of the companies mentioned. You can check out what Matt is keeping an eye on by visiting his CAPS portfolio, or you can follow Matt on Twitter @KoppTheFool or Facebook. The Fool's disclosure policy prefers dividends over a sharp stick in the eye.