Licking the spoon for a couple tastes of raw cookie dough is an added bonus to the baking process, especially at holiday time, but the risk of falling ill from the batter might be greater than once thought.

New research published in the journal Clinical Infectious Disease found that the culprit of a 2009 multi-state E. coli outbreak was none other than the ready-to-bake prepackaged cookie dough found in most grocery stores. At the time of the outbreak, 77 people from 30 states became ill from the bad batter. About half of those people got so sick they had to be hospitalized.

After a thorough investigation, researchers at the Centers for Disease Control still have yet to fully pinpoint the ingredient in the cookie dough that caused the outbreak, but CDC study author Dr. Karen Neil said researchers believe the problem was in the flour. Raw flour does not go through the same rigorous process to kill pathogens the way in which eggs, molasses and sugar do in commercial products.

"You should not consume raw cookie dough or any other raw product that's intended to be baked or cooked, and food should always be prepared according to the recipe or instructions," Neil told ABCNews.com.

Because eating raw cookie dough is such a popular pastime (during the investigation, several people noted that they bought the uncooked batter with the intention to eat it as is), CDC researchers recommended manufacturers make the product safer as a ready-to-eat product. They also noted that more consumer education should be available about the risks of eating raw products such as cookie dough.

But Dr. William Schaffner, chairman of the department of preventive medicine at Vanderbilt University School of Medicine in Nashville, said characterizing eating cookie dough as a risky behavior might be a bit of a stretch. It's similar to eating a hamburger or steak rare or medium rare, he said.

"Eating cookie dough is part of growing up," Schaffner said. "We know people are going to do it. It's too delicious. It's too much of a habit. To ask people not to do it is like whistling in a graveyard."

Nevertheless, Schaffner did note that commercial cookie dough companies should heed the CDC's advice by making sure its raw products are safe to consume as is.

"In the modern world, we have the potential to distribute a tainted product to a lot of people, so manufacturers should process the materials safely and expect that it could be eaten raw," Schaffner said.

As you bake up a storm this holiday season, Neil recommended to visit www.foodsafety.gov to learn about the best ways to handle raw and uncooked foods to keep you and your family safe and healthy.