Alicyclobacillus spp.: Detection in soft drinks by Electronic Nose

In this paper the skill of an electronic nose to early diagnose the natural contamination by Alicyclobacillus spp. in commercial flavoured drinks is presented. The instrument was able to identify contaminated products at very low bacterial loads (tens of copies/ml), with an excellent classification rate (almost 100%). The identification of Alicyclobacillus spp. by means of the electronic nose was not based on the analysis of the secondary metabolites, as it is done by classical analytical techniques, thus allowing a surprising capability in recognising the contaminated products at early stage of growth. This study strongly suggests the use of the Electronic Noses as screening tools in industrial quality control laboratories but at the same time it underlines some limits still present in the technology.