Određivanje sastava i udjela slobodnih masnih kiselina sira iz mišine te njegova fizikalno-kemijska i senzorska svojstva

doctoral thesis

• Title (english): Characterization of cheese in a sack according to the free fatty acid profile, and physicochemical and sensory properties
• Author: Milna Tudor Kalit
• Mentor: Jasmina Havranek (mentor)
• Committee member: Nada Vahčić (predsjednik povjerenstva)
• Granter: University of Zagreb; Faculty of Food Technology and Biotechnology; Zagreb
• Defense date and country: 2012, Croatia
• Scientific / art field, discipline and subdiscipline: BIOTECHNICAL SCIENCES; Food Technology
• Universal decimal classification (UDC): 636/637 - Animal husbandry and breeding. Produce of domestic animals and game

Abstract

Ciljevi ovog istraživanja bili su utvrditi sastav, količinu, dinamiku nastajanja slobodnih masnih kiselina (SMK), omjer kratkolančanih, srednjelančanih i dugolančanih te omjer zasićenih i nezasićenih SMK, senzorske i fizikalno-kemijske značajke sira, povezanost senzorskih značajki sira sa sastavom i količinom SMK te fizikalno-kemijskim značajkama tijekom različitih faza zrenja sira iz mišine. Istraživanje je provedeno na 25 sireva iz mišine i 13 sireva u kori proizvedenih iz sirovog ovčjeg mlijeka. Rezultati su pokazali značajnu (p<0,05) razliku u fizikalno-kemijskom sastavu i sastavu hlapljivih tvari sira iz mišine i sira u kori tijekom zrenja. Ukupna količina SMK (195,41 mg/100 g sira) na kraju zrenja sira iz mišine upućuje na intenzivnu lipolizu. Tijekom zrenja količina srednjelančanih i dugolančanih SMK značajno je rasla (p<0,05), a na kraju zrenja prevladavale su dugolančane SMK, među kojima su najzastupljenije bile: palmitinska, oleinska i stearinska. Na tijek zrenja i senzorska svojstva sira iz mišine nepovoljno su utjecali veći udio masti, soli, dušičnih frakcija topljivih u vodi i u trikloroctenoj kiselini i ukupnih SMK u siru te je najveću ukupnu senzorsku ocjenu imao sir zrelosti 45 dana. Odzivi senzora elektronskog nosa za sir iz mišine bili su u skladu s fizikalno-kemijskim i lipolitičkim promjenama tijekom zrenja sira iz mišine. Sir iz mišine tijekom zrenja razvija karakterističan profil SMK i fizikalno-kemijski sastav što je rezultiralo specifičnim okusom, mirisom i teksturom sira.

Abstract (english)

The aims of this study were to determine composition, quantity and dinamic of formation of free fatty acids (FFAs), proportion of short, medium and long chain FFAs, saturated and unsaturated FFAs throughout ripening of cheese in a sack, sensory and physico-chemical properties of cheese in a sack throughout ripening, correlations between compositon and quantity of FFAs and physicochemical and sensory properties during cheese ripening. Research was conducted on 25 batches of cheese in a sack and 13 batches of cheese in a rind. The results showed significant (p<0.05) difference in physico-chemical properties and volatile compounds composition between cheese in a sack and cheese in a rind. The content of total FFAs at the end of ripening (195.41 mg/100 g of cheese) indicated intensive lypolisis. The content of mediumchain and long-chain FFAs significantly increased (p<0.05) throughout ripening and the most abundant FFAs at the end of ripening time were palmytic, oleic and stearic acid. Higher contents of fat, salt, nitrogen fraction soluble in water and trichloro-acetic acid and total FFAs in cheese have negatively affected ripening process and sensory properties of the cheese in a sack. The highest total sensory score had cheese matured for 45 days. Electronic nose sensors signals were in agreement with physico-chemical and lipolytical changes throughout the ripening of cheese in a sack. Specific taste, odour and texture of cheese in a sack is the result of its characteristic FFAs profile and physico-chemical composition.

• Keywords: sir iz mišine; zrenje; fizikalno-kemijska svojstva; slobodne masne kiseline; senzorska svojstva
• Keywords (english): cheese in a sack; ripening; physico-chemical properties; free fatty acids; sensory properties
• Language: croatian
• URN:NBN: urn:nbn:hr:159:442520
• Promotion: 2013-06-30
• Study programme: Title: Nutrition; Study programme type: university; Study level: postgraduate; Academic / professional title: doktor znanosti/doktorica znanosti (doktor znanosti/doktorica znanosti)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Access restricted to students and staff of home institution
• Created on: 2018-05-16 10:53:01