Content analysis of dehydroacetic acid in rice flour products in different quarters from Guangdong and Guangxi

Objective To understand the content of dehydroacetic acid in rice flour products in different quarters and preliminarily evaluate its exposure.

Methods A high-performance liquid chromatography (HPLC) method was developed for the determination of dehydroacetic acid content in rice flour products in Guangdong and Guangxi, China. The content of dehydroacetic acid in 230 batches of rice flour product samples from Guangdong and Guangxi was determined and compared.

Results The content of dehydroacetic acid in wet rice noodles was significantly higher than that in dry rice noodles. There was no significant difference in the content of dehydroacetic acid in dry rice noodles across different quarters, with a mean dehydroacetic acid content of 0.016 g/kg. The content of dehydroacetic acid in wet rice noodles varied significantly across different quarters, being 0.216, 0.261, 0.424, and 0.361 g/kg, respectively, with a mean level of 0.322 g/kg. In the dry rice noodle samples, wet rice noodle samples, and dried rice flour product samples, 38.8%, 54.0%, and 44.3% had the content of dehydroacetic acid exceeding the limit, respectively. The daily exposure to dehydroacetic acid ingested from rice flour products was 20.54 mg/d among the residents in Guangdong and Guangxi.

Conclusion The content of dehydroacetic acid in dry rice noodles is low in both Guangdong and Guangxi and the content of dehydroacetic acid in wet rice noodles is significantly higher than that in dry rice noodles.