Seventeen starch noodle manufacturers in Dongguan city, Guangdong Province, were ordered to stop production over the weekend after claims emerged that they had been using illegal additives.
A large quantity of starch noodles were seized and will be subjected to tests following a raid by the Guangdong provincial administration of quality and technology supervision.
The starch noodles are suspected of containing illegal additives and of being made from corn instead of sweet potato, which they were supposed to have been made from, according to the packaging.
The 17 starch noodle producers were all situated in the Daliantang Industrial Development Zone in the city's Wanjiang township.
Starch noodles are an important ingredient and a staple of Chinese cuisine. There is a great variety of noodles and they vary depending on their region of production, ingredients, shape or width, and manner of preparation.
The latest food scandal started to come to light on Thursday when more than 5.5 tons of starch noodles that were suspected of being tainted were confiscated and their producer was put under investigation for allegedly having used black ink, industrial dye and paraffin wax to produce them in Gangkou township in the province's Zhongshan city, according to Guangzhou Daily.
Workers from that company claimed that nearly 50 tons of apparently tainted starch noodles had been produced by the firm and had entered the market since it started business in February.
Workers said the unusual ingredients were used in an attempt to lower production costs and create fake noodles that appeared to be made of sweet potato, the report said.
Noodles made from sweet potato are more popular and therefore more expensive in stores.