Utjecaj netoplinskih tehnologija na fizikalna i mikrobiološka svojstva smoothieja kao alternativa konvencionalnom postupku obrade

master's thesis

• Title (english): The effect of nonthermal technologies on physical and microbiological properties of smoothie as an alternative to conventional processing procedure
• Author: Ema Jambrović
• Mentor: Tomislav Bosiljkov (mentor)
• Committee member: Sven Karlović (član povjerenstva)
• Granter: University of Zagreb; Faculty of Food Technology and Biotechnology; (Department of Process Engineering); (Laboratory for Unit Operations); Zagreb
• Defense date and country: 2020-12-17, Croatia
• Scientific / art field, discipline and subdiscipline: BIOTECHNICAL SCIENCES; Food Technology

Abstract

Konzumacija smoothieja porasla je u posljednje vrijeme jer je sve više znanstvene literature na temu nutritivno vrijednog prehrambenog proizvoda. Cilj ovog diplomskog rada je ispitati utjecaj netoplinskih tehnologija ultrazvuka visokog intenziteta i visokog hidrostatskog tlaka na fizikalna (apsorbancija, boja, gustoća, viskoznost i pH) i mikrobiološka svojstva smoothieja (jabuka, mrkva i cikla) s dodatkom sezamovog ulja. Radi usporedbe učinkovitosti, proveden je i toplinski postupak pasterizacije (85 °C/5 '). Temelj ovog rada je praćenje utjecaja ultrazvuka visokog intenziteta na smoothie pri vrijednostima amplituda 60 i 100 %, u periodima od 2, 6 i 10 minuta i promjerima sonde od 6 i 10 mm, kao i praćenje utjecaja obrade visokim hidrostatskim tlakom pri tlakovima od 150, 300 i 450 MPa u periodima od 3, 9 i 15 minuta. Kod obrade ultrazvukom najveći utjecaj na promjenu fizikalnih svojstava ima promjer sonde, dok kod visokog hidrostatskog tlaka je to vrijeme obrade. Obrada visokim hidrostatskim tlakom pokazala je bolji utjecaj na inaktivaciju mikroorganizama od ultrazvuka. Netoplinskim tehnologijama dobivene su znatno bolje vrijednosti apsorbancije u odnosu na toplinsku obradu, pasterizaciju.

Abstract (english)

The consumption of smoothies has increased substantially since scientific literature reported its nutritional value. This thesis aimed to examine the impact of non-thermal technologies, density, viscosity, and pH) and microbiological characteristic of smoothies (apple, carrot & beetroot) with the addition of sesame oil. To compare the efficiency, a thermal pasteurization process (85 °C/5 ‘) was performed. The influence of the high-intensity ultrasound was observed under the following conditions: amplitude 60 and 100 %, time of treatment 2, 6 and 10 minutes, probe diameter 6 and 10 mm, while the influence of the high-hydrostatic pressure was observed under the pressure of 150, 300 and 450 MPa, processing time 3, 9 and 15 minutes. During ultrasound treatments, the biggest impact on the physical properties of the smoothie has a probe diameter, while in high-hydrostatic pressure treatments this is the processing time. Regarding microbiological properties, high-hydrostatic pressure has shown a better influence on the inactivation of microorganisms than ultrasound. Nonthermal technologies have obtained much better absorbance values compared to heat treatment, pasteurization.

• Keywords: ultrazvuk visokog intenziteta; visoki hidrostatski tlak; pasterizacija; smoothie; fizikalna svojstva; mikrobiološka svojstva
• Keywords (english): high intensity ultrasound; high hydrostatic pressure; pasteurization; smoothie; physical properties; microbiological properties
• Language: croatian
• URN:NBN: urn:nbn:hr:159:014688
• Study programme: Title: Food Safety Management; Study programme type: university; Study level: graduate; Academic / professional title: magistar/magistra inženjer/inženjerka upravljanja sigurnošću hrane (magistar/magistra inženjer/inženjerka upravljanja sigurnošću hrane)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2021-01-20 10:33:16