Premium
A selective medium for the rapid detection by an impedance technique of Pseudomonas spp. associated with poultry meat
Author(s) -
Salvat G.,
Rudelle S.,
Humbert F.,
Colin P.,
Lahellec C.
Publication year - 1997
Publication title -
journal of applied microbiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.889
H-Index - 156
eISSN - 1365-2672
pISSN - 1364-5072
DOI - 10.1046/j.1365-2672.1997.00256.x
Subject(s) - pseudomonas , food science , food spoilage , biology , microbiology and biotechnology , pseudomonas aeruginosa , food microbiology , bacteria , genetics
A new medium for detecting and enumerating Pseudomonas spp. associated withpoultry meat spoilage by a rapid impedance technique was developed, after testing potentialgrowth promoters for eight Pseudomonas strains and inhibitors against eight competingstrains (Enterobacteriaceae) able to grow on the medium of Mead and Adams (1977). Four basalmedia (brain heart infusion, brucella broth, Shaedler broth and Whitley impedance broth (WIB))and a synthetic medium were evaluated. Whitley impedance broth was the best basal medium fordetecting variations in impedance in relation to Pseudomonas growth. The efficiency ofWIB was improved by adding compounds which enhanced the growth of Pseudomonas onthe synthetic medium. Among the incubation temperatures tested, 22°C proved to be the bestcompromise between growth of Pseudomonas associated with poultry meat spoilage andinhibition of competitors. Among the 15 inhibitory substances evaluated against Pseudomonas competitors, five were chosen for inclusion in the final medium : metronidazole,carbenicilline, cetrimide, cycloheximide and diamide (MCCCD medium). Preliminary resultsobtained from experiments with beef and pork meat showed that this medium could also be usedwithout diamide and at an incubation temperature of 25°C. The impedance technique usingMCCCD medium was then compared with an official method which uses the medium of Meadand Adams (1977) on 106 samples of poultry neck skin. The linear regression coefficient betweenthe two techniques was approximately r = 0·85. Impedance was able to detect 10 3 Pseudomonas g −1 within less than 19 h making it a promisingtechnique for predicting poultry meat spoilage.