Decrease in optical density as a results of germination of Alicyclobacillus acidoterrestris spores under high hydrostatic pressure

† This paper was presented at the 8th International Conference on High Pressure Bioscience & Biotechnology (HPBB 2014) in Nantes (France) 15–18 July 2014.

Abstract

Alicyclobacillus acidoterrestris is a spore-forming bacterium, causing spoilage of juices. The spores of these bacteria have the ability to survive in the typical conditions used for thermal pasteurization. Therefore, the use of other techniques such as high hydrostatic pressure is considered for their inactivation. The effect of hydrostatic pressure of 200–500 MPa, at temperatures 4–50 °C for 15 min, on the dynamics of germination of A. acidoterrestris spores in apple juice and pH 4 buffer was studied. To estimate the share of germinated spores, the method of determining the optical density at a wavelength of 660 nm (OD₆₆₀) was used. Parameters of hydrostatic pressure treatment used in this work affected the dynamics of germination of A. acidoterrestris spores in apple juice, and the temperature had the greatest effect. The results indicate that nutrients present in apple juice can promote the germination of A. acidoterrestris spores.

Keywords:

• Alicyclobacillus acidoterrestris
• high hydrostatic pressure
• spores germination
• optical density

Disclosure statement

No potential conflict of interest was reported by the authors.

Notes

† This paper was presented at the 8th International Conference on High Pressure Bioscience & Biotechnology (HPBB 2014) in Nantes (France) 15–18 July 2014.