Impact of high intensity ultrasound on the quality of skim milk

master's thesis

• Title: Utjecaj ultrazvuka visokog inteziteta na kvalitetu obranog mlijeka
• Author: Ivan Mihaljević
• Mentor: Rajka Božanić (mentor)
• Granter: University of Zagreb; Faculty of Food Technology and Biotechnology; (Department of Food Engineering); (Laboratory for Technology of Milk and Milk Products); Zagreb
• Defense date and country: 2014-09-23, Croatia
• Scientific / art field, discipline and subdiscipline: BIOTECHNICAL SCIENCES; Food Technology

Abstract

Svrha ovog rada bila je ispitati utjecaj ultrazvuka visokog intenziteta na fizikalna i senzorska svojstva obranog mlijeka te utjecaj na mikrobiološku kvalitetu obranog mlijeka. Uzorci mlijeka su tretirani ultrazvukom sa ciklusom od 100% i 80% kroz 10, 15 i 20 minuta. U ispitivanjima je korišten ultrazvuk visokog intenziteta i sonda promjera 12,7 mm. Mikrobiološka kvaliteta mlijeka određivana je mjerenjem ukupnog broja bakterija, koliformnih bakterija te kvasaca i plijesni. Svi dobiveni rezultati su uspoređivani sa rezultatima pasteriziranog mlijeka. Rezultati nisu pokazali visoku djelotvornost ultrazvuka na inaktivaciju mikroorganizama. Svi uzorci tretirani ultrazvukom su bili lošije senzorski ocijenjeni od netretiranog i pasteriziranog mlijeka.

Abstract (english)

The aim of this study was to examine the impact of high intensity ultrasound on the physical and sensory properties of skim milk and the impact on the microbiological quality of the milk. Milk samples were sonicated with a cycle of 100 % and 50 % for 10,15 and 20 minutes. The tests used the high intensity ultrasound and probe diameters of 12,7 mm. The microbiological quality of the milk was determined by measureing the total bacterial count, coliform bacteria and yeasts and molds. All the results obtained were compared with the results of pasteurized milk. Results did not show high performance ultrasound to inactivate microorganisms. All samples were treated with ultrasound were rated worse than untreated and pasteurized milk.

• Keywords: ultrazvuk; mlijeko; kvaliteta
• Keywords (english): ultrasound; milk; quality
• Language: croatian
• URN:NBN: urn:nbn:hr:159:643422
• Study programme: Title: Prehrambeno inženjerstvo; Study programme type: sveučilišni; Study level: diplomski; Academic / professional title: magistar/magistra inženjer/inženjerka prehrambenog inženjerstva (magistar/magistra inženjer/inženjerka prehrambenog inženjerstva)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Restricted access
• Created on: 2017-05-02 10:26:08