Principles of Food Sanitation

ATP. An automated luminometer can detect
the presence of yeast, mold, or bacterial cells
in liquid samples in 3 minutes (Figures 3–3
and 3–4). A computer-interfaced luminome-
ter, which employs customized software, a
printer, and an automatic sampler, can ana-
lyze samples with a sensitivity of 1 microor-
ganism per 200 mL. Use of this method has
increased because of the need for more rapid
results from product testing. It requires
approximately 12 days for products to flow
from microbial testing to the distribution
center and out to retailers. Use of a rapid
method, such as bioluminescence, acceler-
ates product release to less than 24 hours. A
surface contamination test that requires 2 or

3 days using agar based testing methods can

be reduced to 30 seconds. The incorporation

of new, highly sensitive biochemical reagents

that emit light when in contact with ATP

molecules has permitted rapid microbial

screening to detect extremely low levels of

microorganisms.

Benefits of rapid methods testing and the

reduced risk of contamination have enhanced

the evolution of bioluminescence technol-

ogy as a reliable rapid test for microbial

contamination. Although agar plate-based

The Relationship of Microorganisms to Sanitation 59

Figure 3–3Swab for a rapid hygiene test. (Courtesy
of Ecolab Inc., St. Paul, Minnesota.)

Figure 3–4Device for the rapid determination of

hygienic conditions.