Utjecaj pulsirajućeg električnog polja na inaktivaciju mikroorganizama

undergraduate thesis

• Title (english): Influence of pulsed electric field on inactivation of microorganisms
• Author: Petra Kalčić
• Mentor: Višnja Stulić (mentor)
• Granter: University of Zagreb; Faculty of Food Technology and Biotechnology; (Department of Food Engineering); (Laboratory for Food Processes Engineering); Zagreb
• Defense date and country: 2022-06-14, Croatia
• Scientific / art field, discipline and subdiscipline: BIOTECHNICAL SCIENCES; Food Technology

Abstract

Cilj ovog rada bio je istražiti utjecaj pulsirajućeg električnog polja na inaktivaciju kvasca Saccharomyces cerevisiae ATCC 204508 i gram pozitivne bakterije Lactobacillus plantarum 74. Uzorci su tretirani pri naponima od 30, 40 i 50 kV cmˉ¹, frekvencijama od 100 i 200 Hz, trajanju pulsa od 0,5 i 1 μs te vremenu tretiranja od 60 i 300 s. Najviša inaktivacija (1,8 log10 broj stanica mLˉ¹) za kvasac S. cerevisiae očitana je pri naponu od 50 kV cmˉ¹, frekvenciji od 200 Hz, vremenu trajanja pulsa od 0,5 μs te nakon 60 s trajanja procesa. Potpuna inaktivacija (7,69 log10 broj stanica mLˉ¹) bakterije L. plantarum postignuta je pri naponu od 50 kV cmˉ¹, frekvenciji od 200 Hz, vremenu trajanja pulsa od 0,5 μs te nakon 300 s trajanja procesa. Maksimalan utrošak energije za kvasac S. cerevisiae iznosio je 834 kJ Lˉ¹, a za bakteriju L. plantarum 894 kJ Lˉ¹.

Abstract (english)

This study aimed to investigate the effect of pulsed electric field on the inactivation of yeast Saccharomyces cerevisiae ATCC 204508 and gram-positive bacteria Lactobacillus plantarum 74. Samples were treated at voltages of 30, 40, and 50 kV cmˉ¹, frequencies of 100 and 200 Hz, pulse duration of 0,5 and 1 μs, and treatment times of 60 and 300 s. The highest inactivation (1,8 log10 CFU mLˉ¹) for yeast S. cerevisiae was obtained at a voltage of 50 kV cmˉ¹, frequency of 200 Hz, pulse duration of 0,5 μs, and after 60 s of treatment time. Complete inactivation (7,69 log10 CFU mLˉ¹) of bacteria L. plantarum was achieved at a voltage of 50 kV cmˉ¹, frequency of 200 Hz, pulse duration of 0,5 μs, and after 300 s of the treatment process. The maximum energy consumption for the yeast S. cerevisiae was 834 kJ Lˉ¹ and for the bacteria, L. plantarum was 894 kJ Lˉ¹.

• Keywords: pulsirajuće električno polje; inaktivacija; S. cerevisiae; L. plantarum
• Keywords (english): pulsed electric field; inactivation; S. cerevisiae; L. plantarum
• Language: croatian
• URN:NBN: urn:nbn:hr:159:941729
• Study programme: Title: Food Technology; Study programme type: university; Study level: undergraduate; Academic / professional title: sveučilišni/a prvostupnik/prvostupnica (baccalaureus/baccalaurea) inženjer/inženjerka prehrambene tehnologije (sveučilišni/a prvostupnik/prvostupnica (baccalaureus/baccalaurea) inženjer/inženjerka prehrambene tehnologije)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2022-10-06 08:43:10