Comparison of spindle and stomacher efficacy for detaching biofilms from stainless steel, PVC, and green leafy vegetable surfaces

Abstract

Purpose Biofilms are bacterial communities embedded in exopolysaccharide, enhancing the difficulty of detaching bacterial cells from surfaces. Due to structural properties, it is difficult to detach biofilms. Many removal methods have been developed, but there are still some limitations such as sample size and reproducibility. “Spindle” was developed, producing a higher quality suspension which can be used for further study. The paper aims to discuss these issues. Design/methodology/approach The authors compared the enumeration of biofilm-forming cells detached from the spindle and stomacher in various surfaces. First, the authors chose stainless steel and polyvinyl chloride to attach biofilms and to be subjected to stomacher and spindle for up to 2 min. Also, the authors evaluated the efficiency of detachment from vegetable surfaces. Findings In a comparative experiment of abiotic surfaces, the spindle showed identical effectiveness for detaching biofilm-forming cells compared to the stomacher, recovering the population by 8-log for Escherichia coli O157:H7, Salmonella Typhimurium and Listeria monocytogenes. The spindle also showed no significant difference from the stomacher in the number of recovered cells which is 4-log from vegetable surfaces. However, turbidity after spinach was subjected to spindle was 4.37 NTU, while it was 99 NTU for stomacher, which was in accord with visual result about clearance. Originality/value This study demonstrated that the spindle is a useful to separate biofilms from surfaces without destructing structure, and thus it can be used for analysis in food laboratories as well as utilized for vegetable washing step in the food industry.