Electronic nose investigation of Alicyclobacillus acidoterrestris inoculated apple and orange juice treated by high hydrostatic pressure

Abstract

There is an increasing consumer demand for fresh, shelf stable and healthy products with the favourable sensory properties of the original material food. In the beverage industry the appearance of Alicyclobacillus acidoterrestris spp. presents a problem which has to be solved. In this study the effectiveness of combined high hydrostatic pressure and heat treatment was investigated to examine its microbiological reducing ability regarding the A. acidoterrestris DSMZ 2498 in commercial pasteurized apple- and orange juice. In addition it was studied whether the electronic nose is able to show the differences during the 4 weeks storage time regarding the decreasing number of microorganisms which is in connection with aroma changes.It was established that the combined heat- and high pressure treatment caused microbial inactivation of acidoterrestris at different levels dependent on the combination of applied treatment parameters. These differences could be followed also by the electronic nose.