Utjecaj interakcije procesnih parametara ultrazvuka visokog intenziteta na fizikalna svojstva ovčjeg mlijeka

master's thesis

• Title (english): Influence of high intensity ultrasound process parameters interactions on phisical properties of sheep milk
• Author: Zinka Pirija
• Mentor: Mladen Brnĉić (mentor)
• Granter: University of Zagreb; Faculty of Food Technology and Biotechnology; (Department of Process Engineering); (Laboratory for Unit Operations); Zagreb
• Defense date and country: 2010-07-16, Croatia
• Scientific / art field, discipline and subdiscipline: BIOTECHNICAL SCIENCES; Food Technology

Abstract

Cilj ovog istraţivanja bio je ispitati utjecaj interakcije parametara ultrazvuka visokog intenziteta konstantnih frekvencija od 30 i 24 kHz, i nominalnih snaga od 100 i 200W na fizikalna svojstva ovčjeg mlijeka. Praćen je utjecaj sljedećih parametara ultrazvuka: amplitude A (20%, 60% i 100%), promjera sondi d (7, 10 i 14 mm), ciklusa c (0,6; 0,8 i 1) i vremena obrade mlijeka t (2, 6, 10 i 15 min) na promjenu temperature, pH-vrijednosti i gustoće, kao i njihov utjecaj u intrakciji. Rezultati istraživanja statistički su obrađeni pomoću programskog paketa „Statistica 9“. Jačina i raspored utjecaja procesnih parametara (c, A, t i d) i međudjelovanja tih procesnih parametara na pojedina fizikalna svojstva, prikazani su dijagramima vjerojatnosti (Probability Plot). Probability Plot na apscisi ima vrijednosti standardiziranog koeficijenta utjecaja, a na ordinati odstupanja od očekivane vrijednosti, unutar intervala pouzdanosti. Individualan utjecaj parametara prikazan je preko p – vrijednosti i standardiziranog koeficijenta utjecaja β dobivenih linearnom i kvadratnom metodom, dok su β i p – vrijednosti za parametre u interakciji dobivene linearnom i linearno-kvadratnom metodom ANOVA-e. Usporedbom dobivenih rezultata zaključujemo koji model bolje opisuje utjecaje parametara. Dobiveni rezultati pokazali su da je linearni model pogodniji za interpretaciju utjecaja procesnih parametara na promjenu temperature, dok je za interpretaciju promjene pH i gustoće pogodniji kvadratni model.

Abstract (english)

Main goal of this research was to examine the influence of high intensity ultrasound process parameters, with constant frequency of 30 and 24 kHz, and nominal power of 100 and 200W, on phyisical properties of sheep's milk. Changes in temperature, pH and density were measured under following conditions: amplitude A (20, 60 and 100%), probe radius d, processing time t (2, 6, 10 and 15 minutes) and applied cycle c (0,6; 0,8 and 1). Obtained results were processed in Statistica 9 Software. Strenght and disposition of process parameter influence (A, t, c), as well as influence of process parameter interactions on each phyisical property (T, pH, ρ) are presented by Probability Plot. On x-axis of Probability plot there are standardized effect estimate values (β), and on y-axis there are expected normal values. p and β- value (standardized effect estimate), calculated using linear and quadrate model, represent individual parameter influence. Influence of parameter interactions are presented by p and β- values that are calculated using linear and linear/quadrate two-way ANOVA. By comparing those models we can see which model describes the results better. Obtained results indicated that linear model interpretes better the influcence of parameters on temperature, and quadrate model interpretes better the influcence of parameters on pH and density.

• Keywords: ultrazvuk; fizikalna svojstva; ovčje mlijeko; interakcije
• Keywords (english): ultrasound; phyisical properties; sheep's milk; interactions
• Language: croatian
• URN:NBN: urn:nbn:hr:159:425203
• Study programme: Title: Biotechnology; specializations in: Biochemical Engineering; Course: Biochemical Engineering; Study programme type: university; Study level: graduate; Academic / professional title: diplomirani inženjer biotehnologije; smjer biokemijsko inženjerstvo (diplomirani inženjer biotehnologije; smjer biokemijsko inženjerstvo)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Access restricted to students and staff of home institution
• Created on: 2017-08-25 12:18:59