ARS | Publication request: Effect of stomaching on numbers of bacteria recovered from chicken skin

Submitted to: Southern Poultry Science Society Meeting Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: October 10, 2008
Publication Date: January 26, 2009
Citation: Hannah, J.F., Cason Jr, J.A., Richardson, L.J., Cox Jr, N.A., Hinton Jr, A., Buhr, R.J., Smith, D.P. 2009. Effect of stomaching on numbers of bacteria recovered from chicken skin [abstract]. Southern Poultry Science Society Meeting Abstracts. 88(S1):p. 218:206.

Technical Abstract: Compared to rinsing, stomaching releases only a few more bacteria from a skin sample, but successive rinses continue to remove almost as many bacteria as the first rinse. One hypothesis to explain this observation is that relatively violent treatment of skin generates smaller pieces of skin thus increasing surface area and effectively sequestering bacteria so that fewer are suspended in the rinse liquid. An experiment was conducted to determine whether inoculated marker bacteria disappear from rinse liquid as skin pieces are stomached and naturally occurring bacteria are released. In each of 4 replications, 5 pre-chill broiler carcasses were collected from a commercial processing plant. Two 5 g pieces (n=40) of breast skin were removed from each carcass and placed in a stomacher bag. Thirty mL of 0.85% saline solution containing 104 Salmonella Typhimurium per mL was added to each sample. Skin samples were hand massaged for 30 s to mix the inoculum, after which a 1 mL aliquot was removed for counting bacteria. A similar sample was taken after 4 min of vigorous stomaching of the skin sample. Bacterial counts recovered from the 30 second hand massage were 4.3, 2.7, 2.6, and 3.7 log10 cfu/mL of rinsate for APC, coliforms, E. coli, and Salmonella, respectively. After stomaching, counts were 4.3, 2.9, 2.8, and 3.8, respectively. There was no difference in APC, but mean coliform and E. coli counts were significantly higher (P<0.05) after stomaching. Numbers of inoculated Salmonella did not decrease. Breaking up skin into smaller pieces by stomaching did not remove bacteria from the suspension.