Utjecaj ultrazvuka visokog intenziteta na emulgirajuća svojstva kozjeg i ovčjeg mlijeka

master's thesis

• Title (english): Influence of high intensity ultrasound on emulsifying properties in goat and sheep milk
• Author: Željka Šipek
• Mentor: Suzana Rimac Brnčić (mentor)
• Granter: University of Zagreb; Faculty of Food Technology and Biotechnology; (Department of Process Engineering); (Laboratory for Unit Operations); Zagreb
• Defense date and country: 2011-04-07, Croatia
• Scientific / art field, discipline and subdiscipline: BIOTECHNICAL SCIENCES; Food Technology

Abstract

Cilj ovog istraživanja bio je ispitati utjecaj parametara ultrazvuka visokog intenziteta konstantne frekvencije od 24 kHz na stabilnost emulzija kozjeg i ovčjeg mlijeka izraženog preko Indeksa stabilnosti emulzije (ISE). Praćen je utjecaj ultrazvuka visokog intenziteta snage 400 W na mutnoću, gustoću i viskoznost pri sljedećim procesnim parametrima ultrazvuka: amplituda (A = 37,5; 50; 62,5; 75; 87,5; 100 %); vrijeme obrade (t = 2, 6, 10, 15 minuta); primijenjeni ciklus (c = 0,6; 0,8; 1). Dobiveni rezultati statistički su obrađeni pomoću programskog paketa „Statistica 8“. Vrijednosti ISE izračunate su preko izmjerenih vrijednosti apsorbancija kozjeg i ovčjeg mlijeka. Na povećanje vrijednosti Indeksa stabilnosti emulzije kozjeg i ovčjeg mlijeka podjednako utječu vrijeme obrade i primijenjeni ciklus, dok primijenjena amplituda nema utjecaj. U kozjem i ovčjem mlijeku dolazi do povećanja gustoće i viskoznosti.

Abstract (english)

Main purpose of this research was to explore the influence of high-intensity ultrasound with constant frequency of 24 kHz on the stability of emulsions in goat and sheep milk expressed by the emulsion stability index (ESI). The influence of high-intensity ultrasound (power 400 W) on turbidity, density and viscosity was observed under following conditions: amplitude (A = 37,5; 50; 62,5; 75; 87,5; 100 %); processing time (t = 2, 6, 10, 15 minutes); applied cycle (c = 0,6; 0,8; 1). Obtained results are processed in the „Statistica 8“ software. Values of the ESI were calculated over measured values of absorbance of goat and sheep milk. Processing time and the applied cycle equally influence on the increase of ESI of goat and sheep milk, while the applied amplitude has no effect. It was observed that density and viscosity increases in goat and sheep milk.

• Keywords: ultrazvuk; emulgiranje; kozje mlijeko; ovčje mlijeko
• Keywords (english): ultrasound; emulsification; goat's milk; sheep's milk
• Language: croatian
• URN:NBN: urn:nbn:hr:159:750702
• 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: 2017-05-30 11:47:37