Resistance of vegetative cells and ascospores of heat resistant mould Talaromyces avellaneus to the high pressure treatment in apple juice Original Research Article

Thermoresistant moulds including Talaromyces avellaneus are frequent microbial contamination of fruit juices and purees, which are supposed as food products suitable for pressure pasteurisation. The effect of high pressure treatment on survival of vegetative cells and ascospores of T. avellaneus was studied. The vegetative cells T. avellaneus were very sensitive to high pressure, the sufficient pressure treatment for the reduction by six orders was 200 MPa at 17 °C for 60 min or 300 MPa at 17 °C for 5 min. In apple juice the ascospores of T. avellaneus were relatively resistant to the high pressure treatment, the treatment of 600 MPa at 17 or 25 °C for 60 min reduced their concentration by two or three orders, respectively. Sufficient inactivation rate was obtained when the combination of pressurisation and gentle heating was used, the total reduction (by six orders) was reached at 600 MPa and 60 °C after 60 min.