Fast flow-through non-thermal pasteurization using constant radiofrequency electric fields

Abstract

Abstract Pulsed electric field technologies have captured the attention of researchers on food pasteurization because of their non-thermal inactivation mechanism, which results in fresh-like products. Nevertheless, high voltage pulsing required by these technologies implies complex and costly generators. Here, as an alternative, it is proposed a method, partially inherited from research on cell electroporation for gene transfection, in which the liquid to be treated flows at high speed through a miniature chamber where the electric field is permanently applied. In particular, it is proposed that the constantly applied electric field consists of an AC signal (> 100 kHz) so that electrochemical by-products are minimized. The method, while being compatible with batch processing, will allow use of lower voltages and will avoid the pulsation requirement. The proposal is accompanied by a numerical study and an in vitro study which demonstrate its feasibility. Industrial relevance This paper describes an electroporation based method for non-thermal pasteurization of liquids that, in comparison to existing pulsed electric field technologies, does not require high voltage pulsed generators. The method consists in circulating the liquid at high speed through a miniature chamber where an AC electric field of moderate magnitude is permanently applied. By combining several miniature chambers in parallel and in series batch processing will be possible. Here it is analyzed and demonstrated the performance of a single miniature chamber.