Inactivation mechanisms of radio frequency pasteurisation for food preservation.

 Radio frequency (RF) processing is a novel thermal food preservation technology, which results in enhanced product qualities and processing efficiencies in comparison to traditional thermal methods. However, a major knowledge gap concerns knowledge of the inactivation mechanisms of the technique. This lack of knowledge is caused by exclusively conducting RF pasteurisation studies in real food products. Therefore, we will use artificial food model systems and a small-scale RF set-up to gain fundamental knowledge about RF pasteurisation of food products. Our research will consist of three main parts. First, we will characterise the direct effect of RF on the bacterial cells by focussing on three different inactivation mechanisms, i.e., effects on (i) cell morphology, (ii) the (outer) cell membrane, and (iii) the DNA. We will also investigate whether a part of the inactivation is accomplished by non-thermal effects. Secondly, we will identify and quantify (protective) effects caused by different food microstructural aspects, both on a macroscopic and microscopic scale. Finally, we will characterise the behaviour of cells resistant to RF treatments. The fundamental knowledge obtained in this project will lead to the development of more effective RF treatments.