As of this writing, today's leading percentage gainer on the New York Stock Exchange is American Italian Pasta (NYSE:PLB). The company's fiscal first-quarter earnings announcement is fueling the robust rise -- its stock was up by more than 20% at one point -- but I contend that the good news isn't enough to add pasta to your investment menu.

American Italian Pasta was a clear loser when Americans decided to shun carbohydrates. Before the Atkins and South Beach diets hit their peak in 2004, American Pasta had bulked up to $52.56 a share in 2002. Since then, the stock has been on a diet of its own, falling to an $18.69 low last December.

Before you decide to feed on American Italian Pasta's stock, take a long look at earnings. For the fiscal year, the company expects earnings to be between $0.80 and $1.00 a share; that prices the company at a rich 26 to 32 times forward earnings. Even using analyst-estimated earnings for the following year, the multiple is still plump at 21 times -- and that's based on a hardly outstanding 3.1% increase in sales.

And look at what the company is saying today about sales trends: "Industry-wide retail consumption of dry pasta (as measured by ACNielsen) declined in volume by approximately 2% during the 13-week period ended December 25, 2004, sequentially improving from the 4%-5% decline in the previous 13-week period." It's less of a decline, but a decline nevertheless.

So the news still isn't good for the pasta business. A humorous indication of the stigma that pasta apparently still carries in this low-carb world: Monterey Pasta changed its name in October to Monterey Gourmet Foods (NASDAQ:PSTA).

One part of American Italian Pasta's 2005 strategy is to increase prices, especially for lower-margin private label and ingredient business. Investors should note that first-quarter institutional revenue decreased 12% relative to the year-ago quarter -- an early sign that price increases might lead to sales weakness.

Stocks tend to trade at lower multiples of forward earnings than trailing earnings, but American Italian Pasta's stock price, as a multiple of 2006 estimated earnings, exceeds the trailing price-to-earnings ratio of 20 for the food industry overall. Why pay a high price for pasta when other food stocks, in general, are less expensive?

Cheaper options include former Motley Fool Stock Advisor recommendation Sanderson Farms (NASDAQ:SAFM), with a P/E ratio of 9, or current Hidden Gems pick Fresh Del Monte (NYSE:FDP), trading at 12 times earnings.

Prefer income? Take a look at two Motley Fool Income Investor recommendations. H.J. Heinz (NYSE:HNZ) sells for 17 times earnings and pays a 3.0% dividend. Or look at Sara Lee (NYSE:SLE), with its low 14 P/E ratio and a 3.2% yield.

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Fool contributor W.D. Crotty does not own stock in any of the company's mentioned.