O. Erkmen, ANTIMICROBIAL EFFECT OF PRESSURIZED CARBON-DIOXIDE ON STAPHYLOCOCCUS-AUREUS IN BROTH AND MILK, Lebensmittel-Wissenschaft + Technologie, 30(8), 1997, pp. 826-829
Studies were carried out to assess the use of high pressure CO2 treatm
ent to inhibit Staphylococcus aureus in broth and raw cow's milk at 25
degrees C. Two phases in the survival curves were observed. The early
stage was characterized by a slow rate of decrease in number of S. au
reus; this rate increased sharply at the later stage. Staphylococcus a
ureus suspended in broth was completely inactivated after CO2 treatmen
t at 7 MPa for 100 min and 8 MPa for 60 min. The sterilization effects
of CO2 on both S. aureus and aerobic bacteria were observed at 14.6 M
Pa for 5 h and 9 MPa for 2 h in whole and skim milk, respectively. Sta
phylococcus aureus and aerobic bacteria were more difficult to inactiv
ate when they were suspended in whole milk that may have protected the
cell from penetration by CO2. Reduction rates of S. aureus and aerobi
c bacteria were sensitive to pressure, exposure time and the suspendin
g medium. (C) 1997 Academic Press Limited.