While electronic nose (e.nose) systems have been available for several years, the food industry has been slow to exploit the technology as part of real time quality assurance systems. The EU-funded project - e-nose- found the new tech can be used to quickly detect bacteria, yeasts, filamentous fungi and off-odours.
Researchers, led by Professor Naresh Magan at Cranfield University in the UK, used different types of e.nose systems - based on conducting polymer sensor arrays or metal oxide sensor arrays - for the 'rapid and early cost effective' detection of undesirable, harmful contaminants, toxins and taints in the dairy and bakery product industries.
Magan and his team are now in the final stages of completing e.nose trials in the food industry together with a cost-benefit analysis in areas of the dairy and bakery industries.
One aspect of the project compared the aroma changes of a Danish blue cheese at different stages of ripening, using e.nose, gas chromatography-mass spectrometry (GC-MS) and panel sensory analysis.
"Results showed that the e.nose system was successful in defining the ripening stage of Danish blue cheese, with the same precision as the sensorial analysis and GC-MS analysis," report the researchers.
They found that it is possible to differentiate and detect fungal contaminants in different cheese matrices and that fungal volatile production profiles can discriminate between mycotoxigenic and non-mycotoxigenic strains of some spoilage moulds. In addition, metal oxide sensor arrays were effective in detecting and discriminating between bacterial and mould contamination within 24-48 hours, prior to visible spoilage in bread.
Electronic noses, launched commercially in 1995, are computerised tabletop units with sensors that detect odour molecules. An expensive technology the uptake by the food industry has been slow but in recent years researchers on both sides of the Atlantic have revealed that the noses can be useful tools to save costs through their ability to detect the quality of products.
Areas to date touched on by the electronic noses include detecting the flavours of different kinds of cheese, sniffing the quality of wine and coffee, and detecting fishy seafood before it gets to the consumer.