REAL-TIME DETECTION OF BACTERIA IN FOOD INDUSTRY PROCESSED WATER

Many natural resources, e.g., water, energy, and minerals in fertilizers, are used in crop cultivation and food processing. It is estimated that in addition to the significant water and energy losses due to inefficient farming practices and processing, 30–50% (or 1.2–2 billion tonnes) of all food produced worldwide is lost and wasted. These figures combined with recent estimations that water requirements to meet food demand in 2050 could reach between 10-13.5tn cubic metres per year (about triple of the current annual amount) reveal the urgent need in saving and recovery of water in both horticulture and food industry. Reuse of water in the food industry, with the help of innovative new technologies for water treatment, decontamination and detection, may lead to profound changes in current practices and improve sustainability.

In the framework of RESFOOD project, we develop a novel biosensing platform for rapid detection and identification of microbial contamination in water lines. Our study focuses on the design and fabrication of a prototype device based on porous silicon optical biosensors for bacteria detection. The optical label-free biosensing platform is based on nanostructured oxidized porous silicon (PSiO₂) films, designed to directly capture the target bacteria cells on its surface with no prior sample processing. Exposure of these nanostructured films to the target bacteria results in “direct cell capture” onto the biosensor surface, while these specific binding events induce predictable changes in the thin-film optical interference spectrum of the biosensor. Our biosensing experiments, with “real” processed-water, from different food industries, demonstrate promising results in terms of speed and sensitivity in comparison to conventional microbiological techniques.

Acknowledgement: RESFOOD (Nov. 2012 - Oct. 2015) is a project funded by the 7th Framework Programme of the European Commission.