Effect of Ohmic Heating on Alicyclobacillus acidoterrestris in Orange Juice

Abstract

To study the sterilization mechanism of ohmic heating on Alicyclobacillus acidoterrestris, the microbe was treated by self-made ohmic heating installation. The sterilization effect of ohmic heating on the microbe was observed by environmental scanning electron microscope (ESEM). Conductometer and ultraviolet spectrophotometer was used to detect the variation of bacterial suspension. ESEM photographs of treated Alicyclobacillus acidoterrestris showed that pitting and damage appeared on Alicyclobacillus acidoterrestris’ surface, which resulted from the ohmic heating. And the increase of the electrical conductivity and the OD value indicate the precipitation of the intracellular contents. Results showed that ohmic heating results in the electroporation phenomenon of Alicyclobacillus acidoterrestris.