Kvaliteta polutvrdog kravljeg sira obogaćenog ekstraktom lista masline (Olea europaea L.) tijekom 60 dana zrenja

master's thesis

• Title (english): Quality of semi-hard cow's milk cheese fortified with olive leaf (Olea europaea L.) extract during a 60-day ripening period
• Author: Nicole Madunic
• Mentor: Irena Barukčić Jurina (mentor)
• Mentor: Katarina Lisak Jakopović (pomoć pri izradi, neposredni voditelj)
• Committee member: Katarina Lisak Jakopović (predsjednik povjerenstva)
• Committee member: Tomislava Vukušić Pavičić (član povjerenstva)
• Committee member: Maja Repajić (član povjerenstva)
• 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: 2024-12-20, Croatia
• Scientific / art field, discipline and subdiscipline: BIOTECHNICAL SCIENCES; Food Technology

Abstract

Iako je list masline nusprodukt proizvodnje maslinovog ulja, zahvaljujući bogatom polifenolnom sastavu, njegov dodatak u proizvodnji polutvrdog sira obogaćuje nutritivni sastav sira i tako pospješuje pozitivno djelovanje na ljudsko zdravlje. Cilj ovog rada bio je ispitati učinak dodatka ekstrakta lista masline u proizvodnji polutvrdog sira tijekom 60 dana zrenja. Proizveo se kontrolni sir, bez dodatka ekstrakta, te dva sira obogaćena različitim koncentracijama ekstrakta lista masline. Tijekom zrenja sireva praćena su fizikalna i kemijska svojstva, koncentracija ukupnih fenola i flavonoida, antioksidacijski kapacitet i aktivnost, intenzitet proteolize te mikrobiološka kvaliteta. Utvrđeno je da je dodatak ekstrakta lista masline rezultirao smanjenjem tvrdoće, gumenosti, elastičnosti i sposobnosti žvakanja sira, povećanjem intenziteta proteolize te povećanjem zelenog i žutog tona sira. Nakon 60. dana zrenja, sirevi obogaćeni ekstraktom lista masline sadržavali su veće koncentracije ukupnih fenola te su zabilježene veće vrijednosti antioksidacijskog kapaciteta određenog FRAP metodom.

Abstract (english)

Although olive leaves are a byproduct of olive oil production, their polyphenol-rich composition enhances the nutritional profile of semi-hard cheese when incorporated into its production, contributing to its positive effect on human health. The aim of this study was to evaluate the impact of incorporating olive leaf extract into semi-hard cheese production during a 60-day ripening period. A control cheese was produced, without the addition of the extract, and two cheeses fortified with different concentrations of olive leaf extract. Physical and chemical properties, total phenolic and flavonoid concentrations, antioxidant capacity and activity, proteolysis intensity, and microbiological quality of the cheeses were monitored throughout the ripening period. It was found that the addition of olive leaf extract resulted in a reduced hardness, gumminess, springiness and chewiness of the cheese, an increased proteolysis intensity, and deepened green and yellow hues of the cheese. After 60 days of ripening, the cheeses fortified with the olive leaf extract contained a higher total phenolic concentration and exhibited greater antioxidant capacity, as determined by the FRAP method.

• Keywords: polutvrdi sir; zrenje; ekstrakt lista masline; polifenolni spojevi; antioksidacijska aktivnost
• Keywords (english): semi-hard cheese; ripening; olive leaf extract; polyphenolic compounds; antioxidant capacity
• Language: croatian
• URN:NBN: urn:nbn:hr:159:823693
• Study programme: Title: Food Engineering; Study programme type: university; Study level: graduate; 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: Open access
• Created on: 2025-01-09 11:03:12