Variability in broiler carcass bacterial load at three abattoirs, as measured by a hydrophobic grid membrane filter interpreter

• Published in: Journal of food protection Vol. 56; no. 8; pp. 700 - 705
• Main Authors: McNab, W.B, Renwick, S.A, Lowman, H.R, Clarke, R.C
• Format: Journal Article
• Language: English
• Published: United States 01.08.1993
• Subjects: ABATTOIR; BACTERIA; CARNE DE POLLO; MATADEROS; MEDICION; MEMBRANA; MEMBRANE; MESURE; VIANDE DE POULET
• ISSN: 0362-028X; 1944-9097
• DOI: 10.4315/0362-028X-56.8.700

In this observational study, the variability of broiler carcass bacterial load was investigated at three federally inspected abattoirs, using an automated hydrophobic grid membrane filter interpreter system. The measurement protocol involved: whole carcass rinses aided by a mechanical carcass shaker; filtration of rinse solutions through hydrophobic grid membrane filters (HGMF) (ISO-GRID, QA Laboratories, Ltd., Toronto, Ont.); and use of an automated HGMF interpreter (MI-100 HGMF Interpreter System, Richard Brancker Research, Ltd., Ottawa, Ont.). Carcass and lot mean bacterial loads were measured, respectively, in units of log10 most probable number (MPN) of mesophylic aerobic colony forming units per gram of carcass (LgMPN/g), and slaughter lot mean LgMPN/g (LMLgMPN/g). Whole carcass rinses were conducted on a total of 1,917 carcasses, among 96 slaughter lots from three abattoirs. Overall, the LgMPN/g ranged from 1.054 to 4.180 with a mean of 2.585 and a variance of 0.263. These corresponded to MPN/g counts from 11 to 15,135 and a geometric mean of 385 MPN/g. Statistically significant differences were observed between abattoirs and between lots within abattoirs. The intra-abattoir correlation coefficient of LgMPN/g was r = 0.180 (p 0.001). The within abattoir intralot correlation coefficient was r