Under pressure from animal rights advocates, two soft drink giants, Coca-Cola and PepsiCo, have agreed to stop directly financing research that uses animals to test or develop their products, except where such testing is required by law.

Researchers at People for the Ethical Treatment of Animals sought the assurances after discovering studies financed by the companies that used animals like rats and chimpanzees to test taste perception and, in some cases, to bolster support for promotional health claims.

PepsiCo said that it would stop directly financing animal experiments, including some it had financed through grants given to graduate students through its Gatorade Sports Science Institute.

Elaine Palmer, a spokeswoman for PepsiCo, said that while the company had never supported the idea of animal testing, “We had not been policing it, so that part is new.”

Coca-Cola and PepsiCo are the largest largest manufacturers to agree to the ban.

Coca-Cola also said that it would discontinue a grant given to a researcher at Virginia Commonwealth University who has been studying taste perception in rats, which share certain taste pathways with humans.

Representatives of Coca-Cola and the university declined to say how much financing the company was providing or to elaborate on what the ultimate application of the research might be.

A research associate at PETA, Shalin G. Gala, said, “We see these statements from Coke and Pepsi, massive global conglomerates, as the beginning of the end of all animal tests on food.”

Scientists conducting basic research in animal models have cautioned against PETA’s hard line, saying their work, which may have medical benefits, would not be possible in many cases without help from corporate sponsors.

“It’s very easy to characterize scientific research like this in a bad light,” said Dr. John A. DeSimone, a professor at Virginia Commonwealth University who had been working under the Coca-Cola grant. “To do medical research, you sometimes need an animal model.”

Not everyone agrees with Dr. DeSimone’s thinking, particularly when it involves tests on highly intelligent animals, as did a study involving a Coca-Cola scientist, financed by Nutrasweet, that cut open the faces of chimpanzees to study nerve impulses used in the perception of sweet tastes.

“I have never found chimpanzee work justifiable,” said Dr. Alan Goldberg, director of the Center for Alternatives to Animal Testing at Johns Hopkins University.

Dr. Goldberg said that over the last 30 years, advances in alternatives to animal models, many of which are usually more scientifically precise, have already reduced the number of lab animals in use by 50 percent.

“The bottom line for me is that I’d love to see animal studies disappear entirely,” Dr. Goldberg said. “In vitro models are cleaner.”

The two soft drink giants are the latest companies to respond to scrutiny by PETA, which has mounted a campaign to denounce animal testing practices in the beverage industry, an industry that, unlike cosmetics or pharmaceuticals, had largely been unpublicized in the animal testing arena.

In January, Roll International, the company that makes Pom Wonderful pomegranate juice, agreed to cease tests on animals after PETA disclosed a 2005 study financed by the company that tested the juice to see if it might relieve artificially induced erectile dysfunction in rabbits.

(Published by The New York times, May 31, 2007)