Hanoi police say they busted up a ring of fake monosodium glutamate producers on Saturday.
Bui Dac Chien, 31, was arrested and charged with purchasing MSG of dubious origins and selling it in small packets featuring the logos of trusted brands like Ajinomoto and Miwon.
Chien began the operation in September, buying thousands of empty packs at the Chinese border, VnExpress reported.
Police allege that Chien sold around 125 kilograms of the powder every month.
Many retailers knew that the packs were fake but still bought them due to Chien's low prices.
Police say their investigation began when they stopped a car transporting the questionable packets. They say the driver claimed to be coming from the home of Nguyen Thi Huong, Chien's mother-in-law, and was transporting the cargo for sale in nearby Hoa Binh Province, before it is sold to people of minority groups in the area.
A search at Huong's house revealed hundreds of Ajinomoto and Miwon packs.
Police allege that a large truck arrived at Huong's house every week to distribute the MSG packs. They also claim a team of motorbike drivers helped Chien distribute the powder.