Factors which affect retention ofSalmonellaby chicken muscle fascia

Retention of Salmonella lyphimurium and Salmonella Singapore by chicken muscle fascia after immersion in bacterial suspensions was directly dependent on the concentration of bacteria in suspension. However, more bacteria were retained by tissue immersed in suspensions for 30 min compared with tissue immersed only transiently (ca 15 s) and no significant difference in retention of either test strain used was noted for suspensions prepared in distilled water or physiological saline. Differences in numbers of bacteria retained were correlated with water induced changes in tissue microtopography. By comparison, addition of sodium or magnesium ions (present as chlorides) in concentrations greater than 0.2mol.l‐1, caused significant reductions in retention. Furthermore, optimal retention of both strains occurred at a pH of ca 7. Cells of the test strains used did not attach to collagen fibres associated with fascia when suspension media other than distilled water were used. Treatment of tissue with cetyl pyridinium chloride prevented water induced changes in fascia microtopography and also reduced the number of bacteria retained. On the basis of the experimental data it was concluded that retention is probably a function of the amount of water loosely bound by the connective tissue of fascia.