At ambient temperature and pressure, ultrasonication has little lethal effect on microorganisms. High treatment intensities may cause some microbial inactivation, but simultaneously produce adverse sensory changes in the food. A much more gentle yet effective treatment, termed manosonication (MS), utilizes moderate doses of ultrasonication under mild pressure. Manothermosonication (MTS) describes an MS process that is carried out at elevated temperatures.
studied the inactivation of Y. enterocolitica by combining ultrasonication, pressure and heat. The lethal effect of ultrasonication (20 kHz, 150 Am) increased with rising pressure until an optimum pressure of 400 kPa was reached, when maximum inactivation occurred. Levels of destruction of B. subtilis spores using MTS (20 kHz, 117 Am) followed a similar trend under increasing pressure, with maximum inactivation reached at a pressure of 500 kPa. In both studies, the
lethal effect of pressurization was significantly more pronounced when the amplitude of ultrasonic waves was increased.
also found that the ultrasonic (20 kHz, 117Am) inactivation of L. monocytogenes increased dramatically when the pressure was raised from ambient to 200 kPa. The increase in the inactivation rate became progressively smaller, however, as the pressure was raised from 200 to 400 kPa. The authors theorized that the higher lethality of ultrasound under moderate pressure was due to the higher intensity of cavitation. It should be clarified that the pressures applied during manosonication (e.g. 200 – 600 kPa) are not in the lethal range of pressures applied during HHP treatment.
found the lethality of MTS treatments for bacterial cells, spores and yeast to be 6 – 30 times greater than thermal treatments of equal temperature and concluded that the combined effects of ultrasonication, pressure and heat were synergistic.and also noted enhanced microbial inactivation when MS was combined with temperatures above 50 jC. Unlike the synergism between ultrasound and pressure, however, the lethality of MS plus heat was additive only and appeared to be due to two different mechanisms acting independently.
At ambient temperature and pressure, ultrasonication has little lethal effect on microorganisms. High treatment intensities may cause some microbial inactivation, but simultaneously produce adverse sensory changes in the food. A much more gentle yet effective treatment, termed manosonication (MS), utilizes moderate doses of ultrasonication under mild pressure. Manothermosonication (MTS) describes an MS process that is carried out at elevated temperatures.
studied the inactivation of Y. enterocolitica by combining ultrasonication, pressure and heat. The lethal effect of ultrasonication (20 kHz, 150 Am) increased with rising pressure until an optimum pressure of 400 kPa was reached, when maximum inactivation occurred. Levels of destruction of B. subtilis spores using MTS (20 kHz, 117 Am) followed a similar trend under increasing pressure, with maximum inactivation reached at a pressure of 500 kPa. In both studies, the
lethal effect of pressurization was significantly more pronounced when the amplitude of ultrasonic waves was increased.
also found that the ultrasonic (20 kHz, 117Am) inactivation of L. monocytogenes increased dramatically when the pressure was raised from ambient to 200 kPa. The increase in the inactivation rate became progressively smaller, however, as the pressure was raised from 200 to 400 kPa. The authors theorized that the higher lethality of ultrasound under moderate pressure was due to the higher intensity of cavitation. It should be clarified that the pressures applied during manosonication (e.g. 200 – 600 kPa) are not in the lethal range of pressures applied during HHP treatment.
found the lethality of MTS treatments for bacterial cells, spores and yeast to be 6 – 30 times greater than thermal treatments of equal temperature and concluded that the combined effects of ultrasonication, pressure and heat were synergistic.and also noted enhanced microbial inactivation when MS was combined with temperatures above 50 jC. Unlike the synergism between ultrasound and pressure, however, the lethality of MS plus heat was additive only and appeared to be due to two different mechanisms acting independently.
การแปล กรุณารอสักครู่..