The main objective is the development of rapid and reliable electrical and electromagnetic methods for detection in sterile milk of the total spoilage microflora in less than 8 hours compared with 5 days (including incubation time) by the actual and traditional resazurin test. The consortium is a vertical grouping of 5 organisations (including the two SME subcontractors) from 4 European Union countries, combining organisation with a good track record in European RTD. The skills and backgrounds are complementary and technical and management capabilities are high.
The main objective of this innovative RDT project is the development of more effective physical methods to translate consumer criteria of microbiological quality of sterilised milk into well defined, measurable parameters, including sensors and apparatus for measuring these parameters.
There is a need for more rapid, sensitive, reliable methods that will facilitate product release, and identify hygiene and safety problems more rapidly, so that, corrective action can be taken. These new physical methods easily to be fully automated, will enable and assure quality management and tractability throughout the food chain. It is also essential to control the growth, and survival of micro-organisms that may limit the shelf life of sterilised milk. One of the specific objectives of this project is to design a new generation of predictive model able to forecast the behaviour of micro-organisms in sterilised milk to assure food safety by anticipating risks, offering the possibility to trace the source of contamination throughout the complete food chain, and finally quantify risk factors.
Another specific main technological objective is to reduce the duration of the bacteriological test on sterilised milk, taking the resazurin method and the official incubation test of sterilised milk during 15 days at 30°C (according 91/180/EEG) as the normalised reference method, from several days (including incubation time) to only 8 hours, although 4 hours, whilst optimistic is not unattainable. In the dairy industry, the production of sterilised milk requires that end product contains zero organisms/litre to guarantee its shelf-life of the product.
The expected results are:
- to develop and define two optimum bacterial growths medium to improve the sensibility of detection of spoilage bacteria by different rapid detection techniques developed in the project,
- to design a new generation predictive model to forecast the behaviour of micro-organisms in sterilised milk by performing multifactorial experiments by electrical impedance measurement using the RABIT equipment,
- to develop innovative magnetic methods for concentration and recovery of micro-organisms from a clearer liquor,
- to develop and test other new methods for concentration, and recovery of micro-organisms from a clearer liquor. We want to make a comparison and select the more efficient technology, to achieve at least the same performance as magnetic method, but to reduce this task at only 2 operations (adsorption and desorption stages),
- to develop rapid, reliable and sensitive methods, sensors and apparatus for the early detection of the total spoilage microflora. To assure the complete success of the project, 3 technologies will be examined and compared (in terms of sensitivity, reliability, economic aspect, rapidity etc.) to reach the realistic objective of 8 hours and the optimistic objective of 4 hours. We aim with this multifunction electromagnetic biosensor, to perform simultaneously the amplification of bacterial numbers by incubation, the agglutination of bacteria onto adsorption medium and at the end the early detection of bacteria by an electromagnetic system.
- to do demonstration trials in laboratory, and then directly on a pilot food chain for selection and qualification of the best technique.
We expect this project to lead to proposals to CEN with a view to replacing the resazurin test with this new attractive method.
It is expected, after the end of the project, about two years of additional on site tests at the premises of end-users, and further developments will be needed to make the measurement equipment sufficiently reliable, and user friendly to function in a production environment. Full scale introduction of the system in the market will therefore start about two years after the end of the project.