Zelene metode obrade krumpirove kore za izdvajanje bioaktivnih spojeva

master's thesis

• Title (english): Green methods of potato skin processing for the extraction of bioactive compounds
• Author: Ema Pavlović
• Mentor: Jana Šic Žlabur (mentor)
• Committee member: Jana Šic Žlabur (predsjednik povjerenstva)
• Committee member: Neven Voća (član povjerenstva)
• Committee member: Sanja Fabek Uher (član povjerenstva)
• Granter: University of Zagreb; Faculty of Agriculture; (Department of Agricultural Technology, Storage and Transport); Zagreb
• Defense date and country: 2023-09-27, Croatia
• Scientific / art field, discipline and subdiscipline: BIOTECHNICAL SCIENCES; Agronomy

Abstract

Krumpir je jedna od vodećih prehrambenih kultura u svijetu, a s obzirom da se u industriji prerade krumpir gotovo uvijek guli, nakon njegove prerade zaostaju velike količine biootpada. Upravo zbog navedenog kora krumpira predstavlja značajan problem u odlaganju i zbrinjavanju otpada, te se traže nove metode oporabe prije samog zbrinjavanja. Stoga je cilj ovog diplomskog rada bio utvrditi sadržaj specijaliziranih metabolita i antioksidacijski kapacitet ekstrakata kore krumpira tretirane ultrazvukom visokog intenziteta. Za potrebe istraživanja koristio se lički krumpir sorte 'Viktorija'. Za pripremu ekstrakata od kore krumpira odvagano je 10 g svježe kore i dodano 150 mL otapala etanola prilikom čega je varirana koncentracija istog, 50 i 80 % (v/v). Variran je i način ekstrakcije, klasično (24 h) te ultrazvukom visokog intenziteta prilikom čega je variran tip uređaja, kupelj i sonda, te vrijeme tretmana: 5, 10 i 15 min. Najviši sadržaj vitamina C (4,95 mg/100 g svježe tvari) i neflavonoida (32,18 mg GAE/100 g svježe tvari) zabilježen je kod uzoraka tretiranih ultrazvučnom sondom u trajanju tretmana od 15 minuta i 50 % etanolom kao otapalom. Najviša vrijednost ukupnih fenola zabilježena je kod klasičnog tretmana uz 50 % etanol i u ultrazvučnom tretmanu sondom (15 min) uz 50 % etanol. Najviša vrijednost ukupnih neflavonoida (32,18 mg GAE/100 g sv.t.) utvrđena je kod uzorka tretiranog ultrazvučnom sondom u trajanju od 15 minuta i otapalo 50 % etanol (v/v). Najviše vrijednosti antioksidacijskog kapaciteta prema ABTS (1556,34 μmol TE/L) i FRAP metodi (240,44 μmol TE/L) utvrđene su kod uzoraka tretiranih klasičnom metodom ekstrakcije s otapalom 50 % etanolom (v/v). Temeljem dobivenih rezultata može se istaknuti da je krumpirova kora nusproizvod sa značajnim potencijalom, sadrži nezanemarivu količinu različitih bioaktivnih spojeva visokog antioksidacijskog kapaciteta. Isto tako, ultrazvuk visokog intenziteta pokazao se učinkovitim u izolaciji bioaktivnih spojeva iz kore krumpir čime se ta zelena metoda može smatrati potencijalnom za daljnju oporabu organskog ostatka, bilo u prehrambenoj industriji ili u drugim područjima.

Abstract (english)

Potatoes are one of the most important food crops in the world, and since potatoes
are almost always peeled in the processing industry, large amounts of biowaste remain after
processing. Precisely becau se of the aforementioned potato peel, it represents a significant
problem in the disposal and removal of waste, and new methods of recovery prior to disposal
are being sought. Therefore, the aim of this work was to determine the content of specialized
meta bolites and antioxidant capacity of potato peel extracts treated with high intensity
ultrasound. Lika potatoes of the 'Viktorija' variety were used for the study. For the preparation
of potato peel extract, 10 g of fresh peels were weighed and 150 mL of et hanol was added as
solvent, varying the concentration of the same: 50 and 80% (v/v). The extraction method was
also varied, classical (24 h) and with high intensity ultrasound, varying the type of equipment,
the bath and the probe, and the treatment time: 5, 10, and 15 min. The highest content of
vitamin C (4.95 mg/100 g fresh) and non flavonoids (32.18 mg GAE /100 g fresh) was found in
samples treated with an ultrasound probe at a treatment time of 15 min and 50% ethanol as
solvent. The highest value of to tal phenols was found in the classical treatment with 50%
ethanol and in the ultrasound probe treatment (15 minutes) with 50% ethanol. The highest
value of total non flavonoids (32.18 mg GAE /100 g fw) was found in the sample treated for 15
minutes with ul trasound probe and 50% ethanol solvent (v/v). The highest values of
antioxidant capacity according to ABTS (1556.34 µmol TE /L) and FRAP method (240.44 µmol
TE /L) were obtained in samples treated with classical extraction method with solvent 50%
ethanol ( v/v). Based on the obtained results, it can be concluded that potato peel is a by
product with significant potential, as it contains a considerable amount of various bioactive
compounds with high antioxidant capacity. Similarly, high intensity ultrasound p roved to be
effective in isolating bioactive compounds from potato peel, which means that this green
method can be considered as a potential for further recovery of organic residues either in the
food industry or in other fields

• Keywords: krumpirova kora; bioaktivni spojevi; zelene metode; ultrazvuk visokog intenziteta; antioksidacijski kapacitet
• Keywords (english): potato peel; bioactive compounds; green methods; high intensity ultrasound; antioxidant capacity
• Language: croatian
• URN:NBN: urn:nbn:hr:204:529663
• Study programme: Title: Renewable energy sources in agriculture; Study programme type: university; Study level: graduate; Academic / professional title: magistar/magistra obnovljivih izvora energije u poljoprivredi (magistar/magistra obnovljivih izvora energije u poljoprivredi)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2023-09-29 06:49:36