Kvaliteta kuhanog sira uz dodatak začinskog bilja

master's thesis

• Title (english): Quality of cooked cheese with the addition of spices
• Author: Iva Vaskić
• Mentor: Milna Tudor Kalit (mentor)
• Committee member: Milna Tudor Kalit (predsjednik povjerenstva)
• Committee member: Mirna Mrkonjić Fuka (član povjerenstva)
• Committee member: Iva Dolenčić Špehar (član povjerenstva)
• Granter: University of Zagreb; Faculty of Agriculture; (Department of Dairy Science); Zagreb
• Defense date and country: 2023-09-15, Croatia
• Scientific / art field, discipline and subdiscipline: BIOTECHNICAL SCIENCES; Agronomy

Abstract

Kemijski konzervansi i antimikrobne tvari uobičajeno se koriste u mljekarskoj industriji, posebice u proizvodnji sireva no njihova primjena u novije vrijeme nije dobro prihvaćena od strane potrošača. U tom smislu, dodatak začinskog bilja može biti alternativa. Cilj ovog rada bio je istražiti utjecaj dodatka začinskog bilja (bosiljak i vlasac) na fizikalno-kemijska i senzorna svojstva kuhanog sira te na njegovu mikrobiološku kvalitetu. Kuhani sir proizveden je od punomasnog kravljeg mlijeka u 3 šarže te su proizvedeni sirevi iste šarže podijeljeni u 3 skupine: kuhani sir bez začinskog bilja (kontrolni), kuhani sir s dodatkom vlasca i kuhani sir s dodatkom bosiljka. Fizikalno-kemijske analize sira obuhvatile su određivanje sadržaja suhe tvari, mliječne masti, proteina, soli i pH. U svrhu utvrđivanja mikrobiološke kvalitete začina i sireva provedene su mikrobiološke analize na prisutnost Salmonella spp., sulfitoreducirajuće klostridije, Escherichia coli, Listeria monocytogenes, kvasaca, plijesni, kao i ukupan broj aerobnih bakterija. Uzorkovanje sira za mikrobiološke analize provedeno je odmah po proizvodnji te nakon 45 dana pohrane u hladnjaku. Panel od 5 stručnih ocjenjivača ocijenio senzorna svojstva sira koristeći sustav bodovanja s maksimalnom ocjenom 20. Dodatak začina nije utjecao na fizikalno-kemijska svojstva sira, te je pozitivno utjecalo na senzorna svojstva sira. Mikrobiološka kvaliteta začina izravno je utjecala na mikrobiološku kvalitetu sireva. Uvjeti tijekom pohrane sira u hladnjaku pogodni su za rast i razmnožavanje kvasaca i plijesni.

Abstract (english)

Chemical preservatives and antimicrobial substances are widely used in the dairy industry, especially in the production of cheese, but their use has not been well received by consumers recently. In this sense, the addition of spices can be an alternative. The aim of this work was to investigate the influence of the addition of spices (basil and chive) on the physico-chemical and sensory properties of cooked cheese and on its microbiological quality. The cooked cheese was produced from full-fat cow's milk in 3 batches, and the produced cheeses of the same batch were divided into 3 groups: cooked cheese without spices (control), cooked cheese with the addition of chive and cooked cheese with the addition of basil. The physico-chemical analyzes of the cheese included the determination of the content of dry matter, milk fat, protein, salt and pH value. To determine the microbiological quality of spices and cheeses, microbiological analyses were carried out for the presence of Salmonella spp., sulphite-reducing clostridia, Escherichia coli, Listeria monocytogenes, yeasts, molds, as well as the total number of aerobic bacteria. Sampling of cheese for microbiological analyzes was carried out immediately after production and after 45 days of storage in the refrigerator. A panel of 5 expert evaluators evaluated the sensory properties of the cheese using a scoring system with a maximum score of 20. The addition of spices had no influence on the physico-chemical properties of the cheese, but it had a positive effect on the sensory properties of the cheese. The microbiological quality of the spices directly affected the microbiological quality of cheeses. The conditions during cheese storage in the refrigerator are suitable for the growth and multiplication of yeasts and molds.

• Keywords: kuhani sir; začinsko bilje; fizikalno-kemijska svojstva; mikrobiološka kvaliteta; senzorna svojstva
• Keywords (english): cooked cheese; spices; physical-chemical properties; microbiological quality; sensory properties
• Language: croatian
• URN:NBN: urn:nbn:hr:204:649176
• Study programme: Title: Agroecology; Study programme type: university; Study level: graduate; Academic / professional title: magistar/ magistra inženjer/inženjerka agroekologije (magistar/ magistra inženjer/inženjerka agroekologije)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Access restricted to students and staff of home institution
• Created on: 2023-09-22 11:05:24