Bioelektrička impedancijska analiza u utvrđivanju promjena kakvoće mišićja kalifornijske pastrve (Oncorhynchus mykiss) uslijed brzog smrzavanja

master's thesis

• Title (english): Bioelectrical impedance analysis in determining changes in quality of rainbow trout (Oncorhynchus mykiss) muscle due to fast freezing
• Author: Lana Jerić
• Mentor: Tomislav Petrak (mentor)
• Granter: University of Zagreb; Faculty of Food Technology and Biotechnology; (Department of Food Engineering); (Laboratory for Meat and Fish Technology); Zagreb
• Defense date and country: 2007-02-07, Croatia
• Scientific / art field, discipline and subdiscipline: BIOTECHNICAL SCIENCES; Food Technology

Abstract

Cilj rada bio je ispitati utjecaj jednostrukog i dvostrukog brzog smrzavanja mišićnog tkiva kalifornijske pastrve (Oncorhynchus mykiss) na fizikalne i električke parametre. Mjereni su fizikalni parametri: aktivitet vode, sposobnost vezanja vode, gubitak mase uzrokovan iscijeđivanjem tekućine i pH vrijednost. Elektička mjerenja vršena su u frekvencijskom rasponu od 100 Hz do 1 MHz pomoću uređaja HP RLC Meter 4284A, pri čemu su izmjerene rezistencija i reaktancija. Rezultati su pokazali da kod fizikalnih parametara (pH vrijednost i sposobnost vezanja vode) postoje razlike u vrijednostima svježih i smrznutih uzoraka, dok je gubitak na masi dobar pokazatelj i dvostrukog smrzavanja. Rezultati elekričkih mjerenja rezistencije, impedancije i faznog kuta pri srednjim i visokim frekvencijama su pokazali da postoje razlike ako se uspoređuju svježi i smrznuti uzorci, dok kod vrijednosti reaktancije postoji razlika i između jednostrukog i dvostrukog smrzavanja.

Abstract (english)

The aim of this work was to investigate the influence of single and double fast freezing on physical and electrical parameters of Rainbow trout (Oncorhynchus mykiss). Physical parametars: water activity, the ability of water binding, drip loss and pH –value were measured. The electrical measurements,resistance and reactance, were performed in the frequency range from 100 Hz to 1 MHz with HP RLC Meter 4284A instrument. The results show that physical parameters (pH-value and ability of water binding) show differences in values between fresh and frozen samples, although drip loss also show differences after first and second fast freezing. The results of electrical measurements (resistance, impedance and phase angle) show that at medium and high frequency there are differences, if fresh samples with samples after freezing are compared. The results also show differences after first and second fast freezing for values of reactance.

• Keywords: brzo smrzavanje; bioelekrička impedancija; kalifornijska pastrva (Oncorhynchus mykiss)
• Keywords (english): fast freezing; bioelectrical impedance; rainbow trout (Oncorhynchus mykiss)
• Language: croatian
• URN:NBN: urn:nbn:hr:159:546863
• Study programme: Title: Food Technology; specializations in: Food Engineering; Course: Food Engineering; Study programme type: university; Study level: graduate; Academic / professional title: diplomirani inženjer prehrambene tehnologije; smjer prehrambeno inženjerstvo (diplomirani inženjer prehrambene tehnologije; smjer prehrambeno inženjerstvo)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Access restricted to students and staff of home institution
• Created on: 2017-09-06 10:38:15