Izolacija i karakterizacija prirodne mikroflore i kemijski parametri u svježem siru

master's thesis

• Title (english): Isolation and characterization of natural microflora and chemical parameters in fresh cheese
• Author: Valerija Radošević
• Mentor: Ksenija Markov (mentor)
• Granter: University of Zagreb; Faculty of Food Technology and Biotechnology; (Department of Biochemical Engineering); (Laboratory for General Microbiology and Food Microbiology); Zagreb
• Defense date and country: 2011-09-30, Croatia
• Scientific / art field, discipline and subdiscipline: BIOTECHNICAL SCIENCES; Food Technology

Abstract

Domaći svježi sir proizvodi se od spontano ukiseljenog, sirovog mlijeka. Svrha ovog rada bila je izolirati prirodnu mikrobnu populaciju te odrediti mikrobiološke i kemijske parametre kakvoće u svježim sirevima proizvedenim na obiteljskim gospodarstvima. Istraživanje je provedeno na 17 uzoraka domaćih svježih sireva prikupljenih na zagrebačkim i varaždinskim tržnicama. Iz uzoraka su izolirane bakterije mliječne kiseline, BMK, L. plantarum A, L. casei A i L. delbrueckii A. Izolati BMK su pokazali antimikrobno djelovanje prema patogenim test mikroorganizmima kroz proizvodnju visokih koncentracija mliječne kiseline. Biokemijskim API testovima u uzorcima nisu dokazane patogene bakterije E. coli, S. aureus i L. monocytogenes, ali su uzorci bili mikrobiološki neispravni zbog kontaminacije kvascima i plijesnima. Kemijski parametri su pokazali da prema prosječnom udjelu vode od 79,7%, svi uzorci pripadaju skupini svježih sireva.

Abstract (english)

Fresh domestic cheese is produced from spontaneously soured, raw milk. The aim of this study was to isolate natural microbial population in the domestic cottage cheese and to determine its microbiological and chemical quality parameters. The study was carried out on 17 samples taken from Zagreb and Varaţdin markets. Isolated Lactic acid bacteria, L. plantarum A, L. casei A and L. Delbrueckii A showed significant antimicrobial activity against pathogen test microorganisms seen through production of high concentration of lactic acid. The presence of pathogen bacteria, E. coli, S. aureus and L. monocytogenes, has not been proven by biochemical API tests. However, the samples were microbiologically defective due to contamination by yeast and moulds. According to the water content of 79.66%, all tested samples belong to the group of fresh cheeses.

• Keywords: domaći svježi sir; kemijski parametri kakvoće; mikrobna populacija; mikrobiološki parametri
• Keywords (english): fresh domestic cheese; chemical quality parameters; microbial population; microbiological parameters
• Language: croatian
• URN:NBN: urn:nbn:hr:159:074258
• Study programme: Title: Food Safety Management; Study programme type: university; Study level: graduate; Academic / professional title: magistar/magistra inženjer/inženjerka upravljanja sigurnošću hrane (magistar/magistra inženjer/inženjerka upravljanja sigurnošću hrane)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Access restricted to students and staff of home institution
• Created on: 2017-05-31 12:05:00