Example of a timeline of the microbiological activity in a drinking water pipeline.
Blue line: the course of microbiological activity measured by the ColiMinder; yellow
dots: two manually drawn samples per day
12 · BBII 6/2020
Scientifically proven
ColiMinder has been in use since
2014 and has proven its accuracy
and reliability in many installations
worldwide. The customers of
VWMS include water suppliers,
utilities and industry, as well as numerous
research institutes, including
the Polytechnique Montreal, the
University of Tokyo, the KIT (Karlsruhe
Institute of Technology) and
New Zealand’s National Institute
for Water and Atmosphere. The
technology has already been validated
in several independent and
peer-reviewed scientific studies.
be more obvious than to use the
enzyme activity of the target organisms
as a measure of microbiological
load?
Despite the short measurement
time of 15 minutes, the detection
limit of this enzyme-based method
lies in the range of the usual culture
based methods, in many applications
even significantly below.
Due to the rapid succession of
measurements, short-term fluctuations
and peaks of the microbiological
load are visible, which
would never be detected with traditional
methods. The technology
therefore offers completely new insights
into what is actually happening
and enables a better understanding
as well as evidence-
based response.
of the water with fecal indicators
(E. coli or enterococci) or the total
microbiological activity, which, similar
to the laboratory tests for total
microbial count, records all living
organisms in the sample.
Measuring principle
The measurement principle of this
fast and fully automatic method is
based on a so-called “enzyme
assay,” a scientifically recognized
method in which the enzymatic
activity of the organisms present
in the sample is measured. Living
organisms – bacteria, but also all
other micro organisms such as
algae and fungi – need enzymes for
their metabolism – so what could
Quality Control
and Risk Management
Martin Stone, Director of
HACCP International, sees
the entire process of microbial
risk analysis in food production
in a state of upheaval:
“… if microbiological
monitoring is available in
real-time (…), the risk analysis
system in place up to
now will change completely:
locations and number of
Critical Control Points (CCPs)
will change; and critical limits
can be readjusted – up
to now, a safety margin has
generally been applied. And
if monitoring takes place
directly in the process, the
type and timing of corrective
measures can be changed:
Thus, measures can be
taken before critical limits
are exceeded. (…)” 1)
The ColiMinder at Romaqua – installed at the raw water intake of still and naturally
carbonated mineral water
Microbiology in 15 minutes
The availability of the measurement
results almost in real time now
makes it possible for the first time
to monitor the current status of
the microbiological quality in every
process step – whether at the raw
water intake, during filtration, in
the tank, directly before bottling
or in the end product.
The results for the measured microbiological
activity are displayed
in a timeline which can be called
up live and online at any time. In
addition to the information about
the level of the current microbiological
contamination, form and
course of the activity timeline