Starbucks CEO Kevin Johnson, center, said Monday he wants to add training for store managers on “unconscious bias.” Activists held more protests at a Philadelphia store where two black men were arrested when employees said they were trespassing.

NEW YORK — Starbucks, trying to tamp down a racially charged uproar over the arrest of two black men at one of its stores in Philadelphia, plans to close more than 8,000 U.S. stores for several hours next month to conduct racial-bias training for nearly 175,000 workers.

The announcement Tuesday comes after the arrests sparked protests and calls for a boycott on social media. A video shows police talking with two black men seated at a table. After a few minutes, officers handcuff the men and lead them outside as other customers say they weren’t doing anything wrong. Philadelphia-area media said the two were waiting for a friend.

Starbucks, which once urged its employees to start conversations about race with customers, found itself under fire for its treatment of black people.

The company reacted from a high level: Starbucks CEO Kevin Johnson called the arrests “reprehensible” and said he wanted to apologize to the two men face to face. The company and a lawyer for the two men said they did meet, and Johnson delivered the apology. Starbucks also said the employee who called police no longer works at the store, but declined to give details.

Johnson had also promised to revamp store management training to include the “unconscious-bias” training. Starbucks said Tuesday the company-owned stores and corporate offices will be closed on the afternoon of May 29 for the training. In addition to the company-owned stores, Starbucks had as of January about 5,700 licensed stores in the United States, such as the ones inside Target and Barnes & Noble stores.

The company said the training is “designed to address implicit bias, promote conscious inclusion, prevent discrimination and ensure everyone inside a Starbucks store feels safe and welcome.”

The episode highlights the risks large corporations run when they tie their brands so closely to social messaging. In 2015, then-CEO Howard Schultz shrugged off the ridicule that the “Race Together” message drew and pressed on with his public efforts to engage in the debate over race in America. Johnson was scrambling to keep the Philadelphia incident from shattering the message that Starbucks is a corporation that stands for something beyond profit.

“The more your brand is trying to connect emotionally to people, the more hurt people feel when these kinds of things happen,” said Jacinta Gauda, the head of the Gauda Group, a New York strategic communications firm.