Dairy bacteriophages isolated from whey powder: Thermal inactivation and kinetic characterisation. (May 2017)

• Record Type: Journal Article
• Authors: Wagner, Natalia; Samtlebe, Meike; Franz, Charles M.A.P.; Neve, Horst; Heller, Knut J.; Hinrichs, Jörg; Atamer, Zeynep
• Is Part Of: International dairy journal. Volume 68(2017)
• Page Start: 95
• Page End: 104
• Publication Date: 2017-05
• Subjects: Dairying -- Periodicals; Industrie laitière -- Périodiques; Electronic journals; 338.1762142
• DOI: 10.1016/j.idairyj.2016.12.017
• Languages: English
• ISSNs: 0958-6946

Abstract

Abstract: Fifty three bacteriophages of three lactic acid bacteria species (i.e., Lactococcus lactis, Leuconostoc pseudomesenteroides, Streptococcus thermophilus ) isolated from whey powders and whey powder formulations, were tested for their thermal stability. Complete inactivation of Ln. pseudomesenteroides and S. thermophilus phages required 1 min heating at 85 °C and 90 °C, respectively. L. lactis phages exhibited the highest heat resistance and 16% of them were still detectable after heat treatment at 95 °C for 1 min. The most thermo-resistant phages of L. lactis (P956), Ln. pseudomesenteroides (P973) and S. thermophilus (P1008) were selected to determinate their kinetic parameters and lines of equal effects for 9-log inactivation. High D-values of 105 min (phage P956), 74 min (P973) and 25 min (P1008) were determined for thermal treatments at 75 °C, confirming previous findings that pasteurisation conditions are insufficient for adequate inactivation of thermo-resistant dairy phages.