Utjecaj ultrazvučnog predtretmana na kemijski sastav hibridno osušene hokkaido bundeve

master's thesis

• Title (english): Effect of ultrasound pretreatment on chemical composition of hybrid dried hokkaido pumpkin
• Author: Maja Šturlan
• Mentor: Antonela Ninčević Grassino (mentor)
• Committee member: Marija Badanjak Sabolović (predsjednik povjerenstva)
• Committee member: Sven Karlović (član povjerenstva)
• Committee member: Suzana Rimac Brnčić (član povjerenstva)
• Granter: University of Zagreb; Faculty of Food Technology and Biotechnology; (Department of Chemistry and Biochemistry); (Laboratory for Analytical Chemistry); Zagreb
• Defense date and country: 2023-12-20, Croatia
• Scientific / art field, discipline and subdiscipline: BIOTECHNICAL SCIENCES; Nutrition

Abstract

Pulpa i kora hokkaido bundeve osušene su kombinacijom mikrovalova i vrućeg zraka sa ili bez predtretmana ultrazvukom amplitude 60 i 90 % tijekom 15, 30 i 45 minuta. Kemijski sastav osušenih uzoraka određen je gravimetrijskim, separacijskim i spektrofotometrijskim metodama. Prema dobivenim rezultatima pulpa sadrži veći udio vlage i šećera, a kora veći udio pepela, masti, vlakana i proteina. Ultrazvučni predtretman je utjecao na smanjenja udjela vlage, masti i proteina u uzorcima kore, a predtretirani uzorci pulpe imali su znatno manji udio šećera od netretiranog uzorka. Veći udio vlakana određen je i u kori i pulpi nakon 15, 30 i 45 minuta predtretmana pri amplitudi ultrazvuka od 60 i 90 %. Visok udio masti i proteina u pulpi, odnosno šećera u kori dobiven je kod amplitude ultrazvuka od 60 % nakon 15 minuta. Zaključno, ultrazvučni predtretman svakako doprinosi smanjenju i/ili povećanju udjela određivanih analita, stoga se ovisno o željenoj nutritivnoj vrijednosti uzoraka mogu podesiti i parametri predtretmana.

Abstract (english)

Hokkaido pumpkin pulp and peel were dried by a combination of microwaves and hot air with or without pretreatment with ultrasound at 60 and 90 % amplitude for 15, 30 and 45 minutes. The chemical composition of the dried samples was determined gravimetrically, by separation analysis and spectrophotometrically. The obtained results showed higher mass fraction of moisture and sugar in pulp and higher mass fraction of ash, fat, fibre and protein in peel. Pre-treatment with ultrasound reduced the moisture, fat and protein content in the peel samples and pre-treated pulp samples had a significantly lower sugar content compared to the untreated samples. After 15, 30 and 45 minutes of pre-treatment at an ultrasound amplitude of 60 and 90 %, a higher proportion of fibre was found in both the peel and the pulp. A high content of fat and protein was achieved in the pulp and high content of sugar in the peel at an ultrasound amplitude of 60 % after 15 minutes. In summary, it can be said that ultrasonic pretreatment certainly contributes to reducing and/or increasing the mass fraction of determined analytes. Therefore, the pretreatment parameters should be adjusted depending on the desired nutritional values of the samples.

• Keywords: bundeva; kemijski sastav; predtretman; sušenje; ultrazvuk
• Keywords (english): pumpkin; chemical composition; pretreatment; drying; ultrasound
• Language: croatian
• URN:NBN: urn:nbn:hr:159:724187
• Study programme: Title: Nutrition; Study programme type: university; Study level: graduate; Academic / professional title: magistar/magistra nutricionizma (magistar/magistra nutricionizma)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2024-06-03 13:42:22