Effect of temperature and pH value on the UV-C sensitivity of Escherichia coli and Lactobacillus plantarum. Issue 2 (December 2015)

• Record Type: Journal Article
• Authors: Müller, Alexandra; Pietsch, Valerie L.; Schneele, Jasmin S.; Stahl, Mario R.; Greiner, Ralf; Posten, Clemens
• Is Part Of: Lebensmittel-Wissenschaft + Technologie =. Volume 64:Issue 2(2015:Dec.)
• Page Start: 699
• Page End: 705
• Publication Date: 2015-12
• Subjects: Food industry and trade -- Periodicals; Food -- Composition -- Periodicals; Microbiology -- Periodicals; Nutrition -- Periodicals; 664.005
• DOI: 10.1016/j.lwt.2015.06.013
• Languages: English
• ISSNs: 0023-6438

Abstract

<abstract xml:lang="en" abstract-type="author" id="abs0010"> <title id="sectitle0010">Abstract</title> <sec> <p id="abspara0010">The genetic disposition, the influencing factors of the environment as well as the development status affect the resilience of microorganisms and consequently may influence the inactivation efficiency of an UV-C pasteurization process. In this study, the effect of different growth conditions on the reduction rate of <italic>Escherichia coli</italic> DH5α and <italic>Lactobacillus plantarum</italic> BFE 5092 in Quarter-strength Ringer's solution (QSRS) was investigated. For <italic>E. coli</italic> DH5α, the temperatures below the optimum growth temperature led to higher UV-C resistant cells, whereas incubation at 45 °C facilitated the UV-C inactivation of <italic>E. coli</italic> DH5α. However, no considerably difference in UV-C sensitivity could be observed for <italic>L. plantarum</italic> BFE 5092 incubated at the different growth temperatures applied. In addition, <italic>L. plantarum</italic> BFE 5092, being more sensitive in stationary phase, was more resistant to UV-C than <italic>E. coli</italic> DH5α. No considerably effect on the inactivation efficiency could be observed for both species with regards to the initial pH value of the growth media. The effect of various temperatures and pH values on the inactivation behavior of <italic>L. plantarum</italic> BFE 5092 was also tested and no difference in reduction rates could be observed in the range of 2–40 °C and pH 4.5–7.</p> </sec> </abstract>