Utjecaj tehnologije ultrazvuka visoke snage na stabilnost fenolnih spojeva u sokovima od jagode

undergraduate thesis

• Title (english): The influence of high-power ultrasound technology on the stability of phenolic compounds in strawberry juices
• Author: Paula Bičanić
• Mentor: Danijela Bursać Kovačević (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: 2022-07-18, Croatia
• Scientific / art field, discipline and subdiscipline: BIOTECHNICAL SCIENCES; Food Technology

Abstract

Cilj ovog rada bio je ispitati utjecaj tehnologije ultrazvuka visoke snage (engl. High Power Ultrasound, HPU) na stabilnost fenolnih spojeva u sokovima od jagode prije i nakon sedmodnevnog skladištenja pri 4 °C. Sokovi su pripremljeni od prethodno odmrznutih jagoda (Fragaria x ananassa Duch.) sorte 'Albion', različitih stupnjeva zrelosti (75 % i 100%). Ispitivan je utjecaj parametara HPU tretmana – amplitude (25, 50, 75 i 100 %), pulsa (50 i 100%) te vremena obrade (5 i 10 minuta) na udio ukupnih fenola u uzorcima. U tretiranim i netretiranim uzorcima uočen je veći udio ukupnih fenola kod nižeg stupnja zrelosti jagoda. Skladištenjem netretiranih sokova nije došlo do značajne promjene kon-centracije ukupnih fenola u uzorcima, za razliku od HPU tretiranih sokova kod kojih je uočen pad iste. Povećanjem amplitude kod HPU tretmana koncentracija ukupnih fenola se smanjila, dok puls i vrijeme obrade nisu pokazali značajan utjecaj na njihovu stabilnost.

Abstract (english)

The aim of this study was to investigate the effect of the high-power ultrasound treatment (HPU) on polyphenolic stability in strawberry juice before and after 7-day storage at 4 °C. Juices were made of unfrozen strawberries (Fragaria x ananassa Duch.) cultivar 'Albion', which were harvested at different ripeness stage (75 % and 100 %). The effect of HPU treatment parameters - amplitude (25, 50, 75 and 100 %), pulse (50 and 100 %) and the treatment time (5 and 10 minutes) on total phenolic composition was investigated. In both treated and untreated samples concentration of total phenolics was higher at lower ripeness stage of strawberries. The decrease of total phenolics in treated samples was noticed after storage, while there was no significant difference in the phenolic composition of untreated juice. Increasing amplitude caused a decrease in total phenolics level. Pulse and treatment time did not affect total phenolic stability.

• Keywords: HPU; polifenoli; sok od jagode; stupanj zrelosti
• Keywords (english): HPU; polyphenolics; strawberry juice; ripeness stage
• Language: croatian
• URN:NBN: urn:nbn:hr:159:462763
• Study programme: Title: Food Technology; Study programme type: university; Study level: undergraduate; Academic / professional title: sveučilišni/a prvostupnik/prvostupnica (baccalaureus/baccalaurea) inženjer/inženjerka prehrambene tehnologije (sveučilišni/a prvostupnik/prvostupnica (baccalaureus/baccalaurea) inženjer/inženjerka prehrambene tehnologije)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2022-10-20 09:03:08