Local authorities in central China's Henan Province have vowed to investigate after salt from a major producer in a county known as the “capital of rock salt” was found to have an unusual, unpleasant odor.

The case has triggered public outrage after reports of the smelly seasoning in provinces including Anhui, Shandong, Jiangsu and Guangdong.

The producer in question is Shenying Salt Industry Ltd. in Yexian county, Pingdingshan city. Yexian has a storage capacity of about 330 billion tons of salt.

The salt administration of Henan Province said at a meeting on Saturday that it would trace the accountability of supervisory departments and personnel in the case.

Local authorities have suspended production at Shenying Salt Industry Ltd. and ordered the company to recall at least 7,000 tons of salt sold across the country within 10 days.

Analysis of samples by the Chinese Academy of Sciences and Zhengzhou University found that the odor came from fatty acid contained in the salt. The analysts said even though the substances would do no harm to human health, they would still bar the salt from sale due to its disturbing smell.

Henan's salt administration also said it has launched province-wide inspections of factories, supermarkets and retail stores in order to ensure food security.