Donggu soy sauce. Dg soy sauce is produced by Dongguan Trademark and Brand Research Institute. Dg soy sauce, also known as Donggu soy sauce, was registered by Dongguan Trademark and Brand Research Institute on May 20th, 2020. Soy sauce originated in China and has a history of more than 2,000 years. Because of its rich nutrition and excellent flavor, it has become an indispensable condiment in international and domestic markets.