This article is part of our Rising Star Portfolio series.

Given my love of socially responsible investing, you might wonder how I could even remotely like McDonald's (NYSE: MCD) stock.

The fast-food chain has no shortage of critics. Corporate Accountability International recently called for a "National Day of Action to retire Ronald McDonald," and many activists condemn Mickey D's Happy Meals as wicked tools to market unhealthy food to impressionable children. The documentary Supersize Me, where a dude basically loaded himself up on more McDonald's food than any relatively sane person would regard as good or safe, also gave fast food a bad rap.

Still, some of these stains on the company's image might be historical leftovers from bygone days, even though the company has long since cleaned up its act. In at least a few notable ways, McDonald's can actually be a good corporate citizen.

Making green and going green
Despite the low opinions of its opponents, McDonald's does have major sustainability initiatives under its belt. In fact, in Newsweek's ranking of the 500 Greenest Companies in the U.S. last fall, Mickey D's showed up at No. 79.

McDonald's corporate office employs people who are solely responsible for greening the Golden Arches. In 2009, Fast Company profiled the company's head of corporate social responsibility, Bob Langert, who worked on such goals as eliminating CFCs, recycling polystyrene, buying from sustainable fisheries, and recycling U.K. frying oil into biodiesel.

In addition, Langert was at the helm when McDonald's faced flak from Greenpeace over the company's use of Amazonian soybeans. McDonald's and Cargill made up with Greenpeace by instituting a ban on soybeans from recently deforested areas.

The Golden Arches' dark side
Although McDonald's has done a lot to green up its image, it hasn't completely silenced its critics. Despite the healthier options now available on its kids' menus, the company recently caught flak from the city of San Francisco, which banned its Happy Meals.

And while McDonald's has been trying to improve its environmental reputation, it's hard to ignore cattle's role as a major, flatulent contributor to greenhouse gases. Environmentally minded folks also consider big-business cattle farming a wasteful use of land and water -- a pretty big beef for Mickey D's and its burger-slinging ilk, like Burger King and Wendy's/Arby's (NYSE: WEN), to overcome.

Although the Humane Society of America recently honored companies like Burger King, Subway, and Unilever (NYSE: UL) with Corporate Progress awards, McDonald's remains a high-profile hold-out on making the switch to cage-free eggs. (Its stubbornness only extends to the U.S.; McDonald's already uses cage-free eggs in Europe.)

And while the 2009 documentary Food, Inc. certainly boosted "food with integrity" supporter Chipotle (NYSE: CMG), which helped promote the film, it wasn't so kind to McDonald's, portraying the latter company as a major innovator in mass-produced, factory farmed meat.

No for now
Overall, I believe McDonald's is a rock-solid blue-chip stock. It has made major headways in the way it does business, and if people don't choose the healthier options on its menus (or elect to eat less beef), that's their choice, not McDonald's. The company merely responds to consumers' preferences, as its years of excellent performance prove.

Will things change when Wal-Mart (NYSE: WMT) begins to make good on its vow to provide cheaper healthy foods like fresh produce in its stores? If enough Americans reject Big Macs to eat healthfully and inexpensively, their choices could put a damper on McDonald's consistently robust sales gains.

McDonald's won't show up in my Rising Star portfolio anytime soon; it just doesn't meet the high standard that I want my socially responsible portfolio's holdings to reflect. Despite its significant and admirable positive steps in improving its corporate citizenship, the company presents too much of a mixed bag to earn my full endorsement.

For investors who don't give a flying McNugget about socially responsible investing, this stock's occasional sins don't mean it's not also a winner. But the blemishes on its image do saddle the company with added reputational and competitive risks.

Am I unfairly tarnishing McDonald's halo -- or not being harsh enough? Take our poll and tell me whether McDonald's is a winner or a sinner. If you have further thoughts, share them in the comments box below.

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