Comparison of LST + MUG broth technique and conventional method for the enumeration of Escherichia coli in foods.
OBJECTIVE
To reduce the analysis time needed for the enumeration of Escherichia coli, a rapid fluorogenic method (MUG) which takes only 48 h was compared with the standard most probable number (MPN) method which takes 6 days as described in the International Standards Organization (ISO). This study provides reliability data for the fluorogenic method applied to certain foods.


RESULTS
Both methods were applied to 500 food samples which were analysed for E. coli enumeration. Agreement between the two methods was found in 409 (81 x 8%) samples; 81 (16 x 2%) samples gave higher values by the fluorogenic method, and only 10 (2 x 0%) samples were more effectively assayed by the ISO method. According to statistical analysis, the reliability between the methods was r = 0 x 9706, r(2) = 0 x 9421 and Cronbach's alpha = 0 x 9851. While all three values showed a high degree of correlation (P < 0 x 0001) between the two methods, McNemar's test demonstrated a significant difference between them, indicating that the MUG method was more reliable than the ISO method.


CONCLUSIONS
The data suggest that the fluorogenic method is more reliable and shorter to perform than the standard ISO method.


CONCLUSIONS
Comparison of the two methods may provide a rapid and more reliable alternative for the enumeration of E. coli in food samples.
Dogan
H B
HB
Department of Food Engineering, Faculty of Agriculture, Ankara University, Turkey.
Cakir
I
I
Baspinar
E
E
Halkman
A K
AK
D001431:Bacteriological Techniques / Q000379:methods / Q000592:standards; D003470:Culture Media; D004926:Escherichia coli / Q000302:isolation & purification*; D005456:Fluorescent Dyes / Q000737:chemistry; D005470:Fluorometry / Q000379:methods*; D005516:Food Microbiology; D008461:Meat Products / Q000382:microbiology; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
D003470:Culture Media; D005456:Fluorescent Dyes