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What: Shares of dairy giant Dean Foods (NYSE: DF) were flying high today, gaining as much as 13% in intraday trading after the company reported first-quarter results.

So what: Growth across the business along with tight expense controls led Dean to a quarter that has investors jumping for joy today. Total sales were up 6.7% from a year ago as the company's WhiteWave-Alpro segment chipped in a 13% year-over-year, top-line gain. The profit performance was even better, as adjusted operating income jumped 42% and earnings per share more than doubled to $0.31. Both revenue and earnings topped analysts' expectations.

Now what: According to Dean's management, the good times are set to continue. In the company's press release, CEO Gregg Engles quipped, "Given our significant momentum in the first quarter, the cautious optimism that we expressed last quarter has turned less cautious." That more optimistic view led Dean's management team to boost its full-year, earnings-per-share outlook to a range of $1.10-$1.20 from a previous range of $0.87-$0.95. Analysts had been looking for 2012 EPS of $0.95.

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