TY - JOUR
T1 - Validation of the microbiological methods hygicult dipslide, contact plate, and swabbing in surface hygiene control
T2 - A Nordic collaborative study
AU - Salo, Satu
AU - Laine, Annikki
AU - Alanko, Timo
AU - Sjöberg, Anna-Maija
AU - Wirtanen, Gun
PY - 2000
Y1 - 2000
N2 - A collaborative study on total aerobic bacterial count was conducted to validate the Hygicult®
TPC dipslide against contact plates and swabbing, using stainless-steel
surfaces artificially contaminated with different microbes at various
levels. Twelve laboratories took
part in the validation procedure. The total number of collaborative
samples was 108. The microbial level in each sample was assessed in
triplicate using the 3 above-mentioned methods under 3 different
incubation conditions (at 25 ± 1°C for 48 and 72 h and at 30 ± 1°C
for 48 h). Surface sampling methods detached 25–30% at the lowest
(theoretical yield, 1.4 cfu/cm2), 18–20% at the middle (theoretical yield, 10.7 cfu/cm2), and 16–21% at the highest (theoretical yield, 43.6 cfu/cm2)
levels of microbes from
the test surfaces. The percentage of acceptable results after removing
outliers was 89%. Repeatability standard deviations ranged from 27.2 to
74.6% and reproducibility standard deviations ranged from 42.1 to 97.5%.
There were no significant differences between results obtained at
different
incubation temperatures (25 and 30°C) or incubation times (48 and 72 h)
for all 3 methods. The Hygicult TPC dipslide, contact plate, and
swabbing methods gave similar results at all 3 microbial levels tested:
0.35–0.43 cfu/cm2 at the lowest level, 1.9–2.2 cfu/cm2
at the middle level, and 7.1–9.1 cfu/cm2 at the highest level.
AB - A collaborative study on total aerobic bacterial count was conducted to validate the Hygicult®
TPC dipslide against contact plates and swabbing, using stainless-steel
surfaces artificially contaminated with different microbes at various
levels. Twelve laboratories took
part in the validation procedure. The total number of collaborative
samples was 108. The microbial level in each sample was assessed in
triplicate using the 3 above-mentioned methods under 3 different
incubation conditions (at 25 ± 1°C for 48 and 72 h and at 30 ± 1°C
for 48 h). Surface sampling methods detached 25–30% at the lowest
(theoretical yield, 1.4 cfu/cm2), 18–20% at the middle (theoretical yield, 10.7 cfu/cm2), and 16–21% at the highest (theoretical yield, 43.6 cfu/cm2)
levels of microbes from
the test surfaces. The percentage of acceptable results after removing
outliers was 89%. Repeatability standard deviations ranged from 27.2 to
74.6% and reproducibility standard deviations ranged from 42.1 to 97.5%.
There were no significant differences between results obtained at
different
incubation temperatures (25 and 30°C) or incubation times (48 and 72 h)
for all 3 methods. The Hygicult TPC dipslide, contact plate, and
swabbing methods gave similar results at all 3 microbial levels tested:
0.35–0.43 cfu/cm2 at the lowest level, 1.9–2.2 cfu/cm2
at the middle level, and 7.1–9.1 cfu/cm2 at the highest level.
UR - http://fooddiagnostics.dk/upload/files/Brochurer/Orion/Validatio_of_the_Microbiological_Methods_Hygicult_Dipslide_Contact_Plate.pdf
M3 - Article
VL - 83
SP - 1357
EP - 1365
JO - Journal of AOAC International
JF - Journal of AOAC International
SN - 1060-3271
IS - 6
ER -