Changing a 22-year-old policy on police uniforms, Police Commissioner William J. Bratton announced yesterday that the department would require beat officers to replace their powder blue shirts with navy blue shirts by next October.

"We're getting rid of the Mr. Goodwrench look," Mr. Bratton said.

The department switched from navy to powder blue in 1972 to give the force a softer look after race riots that broke out in cities around the country. But police officials said they found that the light blue shirts all too often showed stains from the jelly doughnuts officers ate for breakfast and the pizza they ate between patrols.

A report recommending the changes that Mr. Bratton approved this week said the uniform change would "send a message to the public of authority, competence and professionalism, while making our officers look trimmer and cleaner."

The report also said: "The corporate culture of our uniform force does not value a clean, well-groomed appearance. Our uniformed officers are often observed by the public in a slovenly condition. This undermines the public's confidence in us."