Utjecaj hladne plazme na kvalitetu nektra soka jabuke tijekom skladištenja

undergraduate thesis

• Title (english): The effect of cold plasma tretament on the quality of apple nectar during the process of storage
• Author: Matea Modec
• 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: 2015-09-09, Croatia
• Scientific / art field, discipline and subdiscipline: BIOTECHNICAL SCIENCES; Interdisciplinary Technical Sciences

Abstract

Cilj ovog rada je bio utvrditi utjecaj hladne plazme na fiziološka ( pH, boju, vitamin C) i mikrobiološka svojstva 50%-tnog nektra soka jabuke tijekom skladištenja te zaključiti može li se tretmanom hladne plazme produžiti rok trajnosti voćnih sokova. Korišten je uređaj za generiranje hladne plazme pri tri različite frekvencije (60, 90, 120 Hz) te su uzorci zagrijani na tri različite temperature (30, 40, 50 ˚C). Na temelju rezultata iz rasta mikrobnih kultura, došlo se do zaključka da hladna plazma je dobar način za produženje roka trajnosti, ponajviše ako se uzorak tretira pri višoj temperaturi i višoj frekvenciji, ali ako se želi zadržat što veća koncentracija vitamina C u nektru jabuke, potrebno je tretirati uzorak pri nižim temperaturama i frekvenciji. Također hladna plazma nije imala značajan utjecaj na promjenu boje nektra jabuke, nego proces skladištenja u kojem su svi uzorci postali svjetliji što se duže skladište zbog razaranja obojenih komponenata soka.

Abstract (english)

The aim of this work was to examine the effect of cold plasma on physiological (value of pH, vitamin C and colour) and microbiological properties of the 50% apple nectar and also determine will the cold plasma tretament prolong shelf-life of fruit juices. Cold plasma was generated in three different frequencies (60, 90, 120 Hz) and the samples were heated in three different temperatures (30, 40, 50 ˚C). The conclusion based on the results of the qrowth of microbiological cultures was that cold plasma is a good way for prolonging shelf-life, mostly for samples treated on higher frequencies and higher temperatures, but for perservation of higher concentration of vitamin C in apple nectar, it was necessary to treat the sample on lower frequencies and temperatures. Also, cold plasma tretament didn't have a considerable effect on the change of colour in apple nectar. Significant effect on the change of colour had storage process in which all the samples became lighter in colour, because of degradation of coloured compounds in the juice.

• Keywords: nektar jabuke; hladna plazma; vitamin C; boja; mikroorganizmi
• Keywords (english): apple nectar; cold plasma; colour; microorganisms
• Language: croatian
• URN:NBN: urn:nbn:hr:159:204532
• 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: 2015-12-14 13:54:36