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item Flores, Rolando

Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 12/1/2003
Publication Date: 12/1/2003
Citation: Flores, R.A. 2003. Transfer coefficients for aerobic bacterial flora among surfaces of beef trim, cutting boards, knives and gloves. Meeting Abstract. p.66.

Interpretive Summary:

Technical Abstract: Microbial risk analyses have identified data gaps in the transfer of pathogenic microorganisms between surfaces and products during the processing steps. These data gaps need to be researched to decrease the uncertainty in process risk analyses. The objective of this study was to determine transfer coefficients of microbial loads between surfaces that simulate a beef fabrication process. Total microflora transfer between beef trim and a hard density polyethylene (HDPE) cutting board, a stainless steel knife and a latex gloved hand were investigated. Beef trims were placed on a HDPE cutting board and each beef trim was crosscut into four pieces with a stainless steel knife. The initial and final microflora levels of the surfaces in contact with the beef trim, cutting board, knife and glove were determined by sponge swabbing. The sponge swabbing efficiency was 81% with a 24% coefficient of variability. To determine the cumulative effect of multiple contacts among the surfaces, the transfer coefficients were calculated at four contact frequencies between the number of trims processed and the contacted surface (1, 5, 10, and 20 trims in contact prior to enumeration). The aerobic load detected on the HDPE board after the first contact with the beef trim was 97% of the load detected on the original beef trim. After five consecutive contacts the load transferred to the HDPE board, knife and glove was 1.22, 0.87 and 0.95 times the original detected load on the beef trim, respectively. The change in the load after five consecutive contacts between the trim and the board, knife, and glove did not vary significantly, indicating that the total load detected was uniform as a consequence of the beef trim material transferred during the contacts. The coefficients determined herein could be applied in studies where the transfer of the total microbial load by contact between the materials studied is needed. However, due to the lack of information about transfer coefficients for pathogenic organisms, the transfer coefficients determined in this study could be applied in risk analyses where there is a need to estimate the pathogenic load transferred among beef trims and HDPE boards and stainless steel knives when processing beef trims.