Although we don't believe in timing the market or panicking over market movements, we do like to keep an eye on big changes -- just in case they're material to our investing thesis.

What: Shares of dairy king Dean Foods (NYSE: DF) were drowned today, losing nearly 18% in intraday trading as investors spit up the company's third-quarter earnings.

So what: Dean Foods' headline earnings per share for the third quarter clocked in at $0.13, down 61% from last year and well short of the $0.21 that Wall Street analysts' were looking for. Revenue for the quarter was up from last year, but much of the increase was from passing on higher input costs to customers. Dean's Fresh Dairy Direct-Morningstar business -- which sells milk and other dairy products -- has been getting squeezed from both sides recently, with input costs rising while consumer frugality is crimping sales prices. Further exacerbating the dour investor sentiment, Dean also announced that its CFO resigned today.

Now what: There was actually some good news hiding out in Dean's results. The company's WhiteWave-Alpro segment, which sells products like Horizon Organic milk and Silk soymilk, saw strong year-over-year gains in both sales and profits. Looking ahead, the company expects that the segment will continue to perform well in the fourth quarter. Unfortunately, management also sees continued pressure on the Fresh Dairy Direct-Morningstar segment, so it's likely that the overall fourth-quarter numbers will still end up smelling a bit sour.

Want to keep up to date on Dean Foods? Add it to your watchlist by clicking here.

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 own shares of 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 on his RSS feed. The Fool's disclosure policy assures you no Wookiees were harmed in the making of this article.