Investigation and analysis of Burkholderia gladioli contamination in the whole process of production and sales of fresh wet rice noodles

Abstract

ObjectiveTo analyze the main causes and sources of contamination， the continuous monitoring of Burkholderia gladioli contamination in the whole process of fresh wet rice noodles production and sales was monitored.MethodsThree rice noodle production enterprises were selected and all raw materials， semi-finished products， finished products and environmental samples were collected according to the process. Strain identification and cluster analysis were performed according to GB 4789.29—2020 combined with VITEK 2 COMPACT biochemical detection， PCR， and MALDI-TOF MS techniques. The bongkrekic acid in food samples， environmental samples， the enrichment fluid and venom were detected by LC-MS/MS.ResultsBurkholderia gladioli was separated and identified in 22 food samples with a detection rate of 31.9% （22/69）. After toxigenic culture， 10 strains produced bongkrekic acid. Among 67 environmental samples， only one Burkholderia gladioli toxic strain was isolated from the inner surface sample of the rice slurry pipeline. The samples with the top three detection rate were 71.4% （10/14） of rice， 66.7% （2/3） of soaked rice and 50% （6/12） of selling products. According to the regional distribution of positive samples， the raw material storage area accounted for 43.5% （10/23）， sales place for 26.1% （6/23），raw material processing area for 21.7% （5/23）， finished product packing area for 8.7% （2/23）， and no positive samples were detected in hot-cure molding area. The cluster analysis showed that positive strain from the rice slurry pipeline were highly homologous to the strains from the same batch of rice slurry.ConclusionRice may be the source of contamination in fresh wet rice noodles products enterprises. Open packaging and room temperature storage and transportation of products may be important reasons for cross-contamination， reproduction and toxicogenesis of Burkholderia gladioli. The raw materials should be separated from other production workshops to prevent the secondary pollution of the finished products. The cleaning and disinfection of the production and sales sites should be strengthened to effectively prevent and control the risk of Burkholderia gladioli contamination.

Keywords

• fresh wet rice noodles
• burkholderia gladioli
• bongkrekic acid
• food safety
• cluster analysis