Budweiser finally reveals what's in its beer

Anheuser-Busch (BUD) has disclosed the ingredients for Budweiser and Bud Light after decades of keeping that information private.

What changed? A popular blogger known as the "food babe" started a petition asking major brewers to list their ingredients. The petition picked up steam, gathering more than 40,000 signatures in 24 hours.

The company responded surprisingly fast, listing its ingredients on the website tapintoyourbeer.com. It turns out Bud and Bud Light have only five ingredients: water, barley malt, rice, yeast and hops.

The blogger, Vani Hari, wrote on foodbabe.com that she was thrilled with the response. "It's pretty amazing that making your voice heard can change the policies of a multibillion-dollar company overnight," she said. One Twitter user called it a smart move. "It's going to happen, might as well lead the way," he wrote.

Hari wrote that she created the petition because her husband drinks beer and she wanted to know what was in the brews. The Treasury Department regulates beer, she said, not the Food and Drug Administration, and as a result brewers aren't required to list their ingredients.

Hari has emerged as a powerful online voice when it comes to food and sourcing of ingredients, and recently persuaded restaurant chain Subway to stop using a food additive in its bread that is also found in some yoga mats and shoe soles. She also pressured Kraft (KRFT) to remove an orange dye from some macaroni and cheese products.

Anheuser-Busch said it will also list the ingredients for its other beers, including Beck's, Busch and Michelob, soon, according to The Associated Press.

The Center for Science in the Public Interest has been trying to get beer companies to list their ingredients for decades, Salon reports, and even lobbied the government to require the disclosure from brewers. Turns out all you had to do was ask -- and have 40,000 people asking with you.

The issue speaks to the growing power of the consumer in influencing how restaurants and food companies source and develop their products. Now more than ever, people want to know what exactly is in the beer, bread and other items they consume. They want restaurants to use fresh ingredients from local providers. They question the necessity of chemicals and other artificial additives.

Now the focus could turn to other brewers to see if they will also list ingredients. Hari specifically called on MillerCoors to disclose next. "We know more about what's in a bottle of Windex and Coca-Cola than we do about one of the world's most popular drinks -- beer," she said.