Stabilnost napitka od lista masline tijekom skladištenja pri sniženoj temperaturi

undergraduate thesis

• Title (english): The stability of olive leaf drink during storage at low temperature
• Author: Monika Ivanković
• Mentor: Branka Levaj (mentor)
• Granter: University of Zagreb; Faculty of Food Technology and Biotechnology; (Department of Food Engineering); (Laboratory for Technology of Fruits and Vegetables Preservation and Processing); Zagreb
• Defense date and country: 2017-09-18, Croatia
• Scientific / art field, discipline and subdiscipline: BIOTECHNICAL SCIENCES; Food Technology

Abstract

U ovome radu cilj je bio ispitati stabilnost napitka od lista masline tijekom 12 tjedana skladištenja pri temperaturi od 8 ⁰C. Svojstva koja su se pratila i analize koje su se provodile su: boja (CIELAB metodom), senzorska svojstva (kvalitativnom deskriptivnom analizom), koncentracija ukupnih fenola (pomoću Folin-Ciocalteu reagensa), antioksidacijski kapacitet (DPPH metodom) te mikrobiološka svojstva. Rezultati pokazuju da se povećanje a, b, C i ΔE vrijednosti te smanjenje L i H⁰ vrijednosti. Koncentracija fenola se vremenom nije značajnije smanjila, kao ni antioksidacijski kapacitet. Skladištenjem su se senzorska svojstva mijenjala i to tako da su se smanjili intenzitet žute boje, miris na list masline, trpki okus, strani miris, a povećao se intenzitet smeđe boje te harmoničnost okusa. Mikrobiološka ispitivanja ukazuju na prihvatljivu stabilnost napitka tijekom skladištenja.

Abstract (english)

In this study, the purpose was to examine the stability of olive leaf drink during 12 weeks of storage at 8 ⁰C. Properties and analyses which were carried out are: color (CIELAB method), sensory properties (qualitative descriptive analysis), concentration of total phenol (with Folin-Ciocalteu reagent), antioxidant capacity (DPPH method) and microbiological properties. Results show that a, b, C and ΔE values were incresed, while L and H⁰ values were decreased. Concentration of total phenol was not significantly reduced and neither was antioxidant capacity. During storage sensory properties changed and showed reduction of yellow color, smell of olive leaf, olive leaf taste, sourness, bitterness, olive leaf aroma and green aroma, while brown color and harmonious taste increased. Microbiological tests indicate satisfactory stability of drink during storage.

• Keywords: antioksidacijski kapacitet; list masline; napitak; skladištenje; ukupni fenoli
• Keywords (english): antioxidant capacity; olive leaf; drink; storage; total phenol
• Language: croatian
• URN:NBN: urn:nbn:hr:159:516211
• Study programme: Title: Nutrition; Study programme type: university; Study level: undergraduate; Academic / professional title: sveučilišni/a prvostupnik/prvostupnica (baccalaureus/baccalaurea) nutricionizma (sveučilišni/a prvostupnik/prvostupnica (baccalaureus/baccalaurea) nutricionizma)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2017-10-05 12:00:24