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Simple test for Enterobacteriaceae gives results in one - seven hours
The MicroSnap product range - a simple, rapid test for bacteria giving results in the same shift - has been extended to include Enterobacteriaceae.
The measurement of Enterobacteriaceae is a useful indicator of surface hygiene and product quality in the manufacture of heat processed food. Simple, rapid tests such as the specific ATP test system (MicroSnap EB) provides results in a working shift.
The test can be applied to solid surfaces for environmental monitoring as well as raw material or finished product testing. It has an excellent agreement with cultural plate count methods and has a huge dynamic range of 1 to 10,000 bacteria in a single test device, such that it can be used for presence / absence test or enumeration purposes. This means that less sample preparation or dilution is required; thus saving time, labour and material costs as well as minimising the requirements for laboratory facilities.
MicroSnap EB (Enterobacteriaceae) is a simple two-step test procedure with a total time to result of seven hours 15 seconds.
The sample can be either a surface swab or 1ml liquid sample or food suspension that is mixed with a proprietary enrichment broth in an all-in-one device and incubated for seven hours at 37°C, after which a 0.1ml aliquot is transferred (using the device itself) to a specific end detection device for measurement in the EnSURE luminometer; giving results in 15 seconds. The specificity of MicroSnap EB was determined by measuring its ability to detect 39 different bacteria in pure culture (22 Entero and 17 Non-Entero bacteria). Both the inclusivity and exclusivity were measured at 95%.
The output of MicroSnap EB is directly related to inoculum size such that greater the number of bacteria to shorter the time to detection. Table 1 shows a typical result (i.e. E. coli) in that ~10 Enterobacteriaceae were detected after the recommended seven hour incubation. The dynamic range of the single test device is 10 - 10,000 bacteria per ml (or swab) thus negating the need for serial dilutions saving labour, materials and time. Conversely a shorter detection time can be set according to the desired specification e.g. 100 Enterobacteriaceae can be detected in five hours. Similar results were obtained for other key organisms including Cronobacter sakazakii.
23rd October 2014