Utjecaj visokoga hidrostatskoga tlaka na kakvoću funkcionalnih napitaka i primjena kemometrije u procjeni njihove kakvoće

doctoral thesis

• Title (english): Effect of high hydrostatic pressure on the quality of functional smoothies and application of chemometry in assessing their quality
• Author: Marko Škegro
• Mentor: Damir Ježek (mentor)
• Committee member: Sven Karlović (predsjednik povjerenstva)
• Committee member: Danijela Bursać Kovačević (član povjerenstva)
• Committee member: Sandra Voća (član povjerenstva)
• Committee member: Mladen Brnčić (član povjerenstva)
• Granter: University of Zagreb; Faculty of Food Technology and Biotechnology; (Department of Food Engineering); (Laboratory for Food Processes Engineering); Zagreb
• Defense date and country: 2022-03-23, Croatia
• Scientific / art field, discipline and subdiscipline: BIOTECHNICAL SCIENCES; Food Technology
• Universal decimal classification (UDC): 578/579 - Virology. Microbiology

Abstract

Smoothie napitci su funkcionalna hrana s velikim potencijalom koji doprinose željenim pozitivnim zdravstvenim učincima, no kratkog su roka valjanosti. Toplinska obrada nepovoljno utječe na izvornu kakvoću, pa se u prehrambenoj industriji sve više koriste netermalne tehnologije obrade poput visokog hidrostatskog tlaka (VHT), s brojnim prednostima u vidu očuvanja kakvoće i zdravstvene ispravnosti tijekom skladištenja. Stoga je cilj ovog rada istražiti učinak VHT na kakvoću smoothie napitka pripremljenih od jabuke, mrkve, aronije, indijanske banane i bademovog napitka tijekom skladištenja (7,14,21 dan/4 °C). Radi usporedbe s toplinskom obradom, uzorci su podvrgnuti pasterizaciji (85 ℃/7 min). U svim ispitivanim uzorcima utvrđeni su slijedeći parametri kakvoće: (i) fizikalno kemijsksa svojstva, (ii) mikrobiološka stabilnost, (iii) stabilnost biološki aktivnih spojeva i (iv) senzorska obilježja. Pored usporedbe učinkovitosti primijenjenih tehnologija obrade u svrhu očuvanja kakvoće funkcionalnih napitaka tijekom skladištenja, uspješno su primjenjene kemometrijske metode za ispitivanje povezanosti analiziranih parametara kakvoće i tehnologija obrade funkcionalnih napitaka (VHT vs. pasterizacija) tijekom skladištenja s ciljem unaprjeđenja kontrole procesa te moguću industrijsku primjenu.

Abstract (english)

Smoothies are functional foods with a great potential to contribute to desired positive health effects, but have a short shelf life. Heat treatment adversely affects the original quality, teherefore non-thermal processing technologies such as high hydrostatic pressure (VHT) are increasingly used in the food industry, offering numerous advantages in terms of maintaining quality during storage. Therefore, the aim of this study was to investigate the effect of VHT on the quality of smoothies prepared from apple, carrot, chokeberry, paw-paw and almond drink during storage (7,14,21 days / 4°C). For comparison with heat treatment, the samples were subjected to pasteurization (85 ℃ / 7 min). The following quality parameters were determined for all tested samples: (i) physicochemical properties, (ii) microbiological stability, (iii) stability of biologically active compounds, and (iv) sensory properties. Besides comparing the efficiency of the applied processing technologies to maintain the quality of functional beverages during storage, chemometric methods were successfully applied to test the relationship between the analyzed quality parameters and the processing technologies for functional beverages (VHT vs. pasteurization) during storage to improve process control and possible industrial application.

• Keywords: visoki hidrostatski tlak; pasterizacija; funkcionalna hrana; smoothie napitak; parametri kakvoće; kemometrija
• Keywords (english): high hydrostatic pressure; pasteurization; functional food; smoothie; quality parameters; chemometrics
• Language: croatian
• URN:NBN: urn:nbn:hr:159:053386
• Promotion: 2022
• Study programme: Title: Postgraduate PhD Study in Nutrition; Study programme type: university; Study level: postgraduate; Academic / professional title: doktor/doktorica znanosti, područje biotehničkih znanosti, polje nutricionizam (doktor/doktorica znanosti, područje biotehničkih znanosti, polje nutricionizam)
• Type of resource: Text
• Extent: 155 str ; 30 cm
• File origin: Born digital
• Access conditions: Open access
• Created on: 2022-11-08 11:09:08