SHANGHAI - Trading of Hong Kong-listed Japanese-style fast food chain operator Ajisen (China) Holding Ltd (ACHL) resumed on Monday, with the share price slumping some 7.24 percent.

Trading was suspended from Aug 5, after the company became involved in a controversy over the ingredients in its noodle soup.

Media reports in late July said that the restaurant chain used concentrated ingredients, even though it claimed the dish was made with fresh ingredients.