Primjena visokonaponskog električnog pražnjenja pri inaktivaciji kvasca Rhodotorula spp.74

undergraduate thesis

• Title (english): Application of high voltage electrical discharge plasmas for inactivation of yeast Rhodotorula spp.74
• Author: Petra Mišković
• Mentor: Zoran Herceg (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: 2016-09-20, Croatia
• Scientific / art field, discipline and subdiscipline: BIOTECHNICAL SCIENCES; Food Technology

Abstract

U ovom radu ispitivan je utjecaj visokonaponskog električnog pražnjenja pri inaktivaciji kvasca Rhodotorula u soku od jabuke. Praćena je promjena pH, temperature, električne vodljivosti i boje soka, te su određivani metali i broj stanica kvasca prije i nakon tretiranja hladnom plazmom. Tretmani su se provodili u trajanju od 5 i 10 minuta pri frekvenciji od 120 Hz. Primjenjivale su se dvije vrste hladne plazme, tekućinska i plinska, s upuhivanjem zraka i s upuhivanjem argona. Ispitivanjem utjecaja hladne plazme pri inaktivaciji kvasca Rhodotorula utvrđeno je da nema znatnog utjecaja na fizikalno-kemijska svojstva (pH, temperatura, električna vodljivost). Tretiranje hladnom plazmom ne utječe znatno na promjenu boje soka od jabuke. U soku tretiranom hladnom plazmom nema opasnosti od prisustva metala. Na temelju rezultata može se zaključiti da se primjenjenom metodom može ostvariti inaktivacija kvasca Rhodotorula, te se najveća inaktivacija postiže primjenom hladne tekućinske plazme s upuhivanjem argona.

Abstract (english)

The aim of this thesis was to examine the effect of high voltage electrical discharge for inactivation of the yeast Rhodotorula in apple juice. Parameters that were monitored before and after the treatment are pH, temperature, electrical conductivity and the color of apple juice, as well as metals and the number of living yeast cells. The treatments lasted for 5 and 10 minutes at the frequency of 120 Hz. Two different methods were applied, using gas and liquid cold plasma, with argon or air blowed into. The study of the effect of cold plasma in the inactivation of yeast Rhodotorula showed that it doesn't have a major influence on physical-chemical features (pH, temperature, electrical conductivity). The treatment doesn't have a major influence on changing the color of apple juice. There is no danger of presence of metals in apple juice after the treatment. Considering the results it can be concluded that the Rhodotorula inactivation can be achieved, and the best results were given when cold liquid plasma with argon was applied.

• Keywords: hladna plazma; pH-vrijednost; električna vodljivost; temperatura; boja; metali; kvasac; argon
• Keywords (english): cold plasma; pH; temperature; electrical conductivity; temperature; color; metals; yeast; argon
• Language: croatian
• URN:NBN: urn:nbn:hr:159:379020
• 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: 2017-04-24 13:31:02