Inactivation of Listeria monocytogenes and Escherichia coli by Ultrasonic Waves Under Pressure at Nonlethal (Manosonication) and Lethal Temperatures (Manothermosonication) in Acidic Fruit Juices
Küçük Resim Yok
Tarih
2014
Dergi Başlığı
Dergi ISSN
Cilt Başlığı
Yayıncı
Springer
Erişim Hakkı
info:eu-repo/semantics/closedAccess
Özet
The inactivation of Listeria monocytogenes and Escherichia coli suspended in apple and orange juices by ultrasound under pressure at nonlethal (manosonication, MS) and lethal temperatures (manothermosonication, MTS) was evaluated. Significant differences were found in the MS resistance (35 A degrees C, 110 mu m, 200 kPa) of three strains of L. monocytogenes and three of E. coli in pH 3.5 buffer, L. monocytogenes STCC 5672 and E. coli O157:H7 being the most resistant strains. Regarding the interspecific differences, L. monocytogenes showed higher MS resistance than E. coli. Although the pH and treatment medium composition did not significantly change the bacterial MS resistance, the effectiveness of ultrasound increased by both raising the amplitude of ultrasonic waves and the pressure. The energy transmitted to the fruit juices by ultrasonic waves at different combinations of amplitudes (46.5, 90, 110, and 130.5 mu m) and pressures (0, 100, and 200 kPa) was also studied, obtaining an exponential relationship between the D (MS) values and power input: an increase of 116 W increased the inactivation rate approximately 10-fold in both juices. The MS resistance of both species decreased when heat was applied jointly with ultrasound (MTS), which was more effective in inactivating L. monocytogenes and E. coli than the sum of MS and heat acting simultaneously but independently. Therefore, MTS showed a synergistic lethal effect in acidic juices, whose magnitude was dependent on the treatment conditions.
Açıklama
Anahtar Kelimeler
Listeria monocytogenes, Escherichia coli, Ultrasound, Manosonication, Manothermosonication, Acidic fruit juices
Kaynak
Food and Bioprocess Technology
WoS Q Değeri
Q1
Scopus Q Değeri
Q1
Cilt
7
Sayı
6
