Biološki aktivni sastojci višnje Maraske tijekom pripreme sirupa

undergraduate thesis

• Title (english): Biological active compounds of sour cherry Maraska during syrup preparation
• Author: Marija Majstorović
• Mentor: Branka Levaj (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: 2013-07-10, Croatia
• Scientific / art field, discipline and subdiscipline: BIOTECHNICAL SCIENCES; Food Technology

Abstract

Zadatak rada je bio odrediti fizikalno-kemijske parametre (suha tvar, pH vrijednost, ukupna kiselost i boja) i biološki aktivne spojeve (ukupne fenole, flavonoide, neflavonoide, antocijane i antioksidacijski kapacitet) u višnji maraski (Prunus cerasus var. marasca) tijekom pripreme sirupa. Sirup je pripremljen na tradicionalan način koji se primjenjuje u kućanstvima stajanjem višnje maraske tijekom jednog mjeseca na suncu u zatvorenoj posudi uz dodatak konzumnog šećera. Uslijed otapanja šećera i izlaženja soka iz stanica ploda, dobije se sirup i djelomično dehidratirani plod višnje. Analizirano je pet uzoraka: svježa višnja kao početna sirovina, plod višnje i sirup nakon dva tjedna, te plod višnje i sirup nakon četiri tjedna. Ukupna suha tvar je izmjerena digitalnim refraktometrom, pH vrijednost pH-metrom, a ukupna kiselost titracijom s otopinom NaOH. Ukupni fenoli i flavonoidi su određeni spektrofotometrijski, antocijani pH diferencijalnom metodom, a antioksidacijski kapacitet DPPH metodom. Prema dobivenim rezultatima, stajanjem na suncu uz dodatak šećera, povećava se udio biološki aktivnih sastojaka u plodu i sirupu višnje, iako je njihova najveća vrijednost zabilježena u kontrolnom uzorku svježe višnje. Najveći udio suhe tvari ima višnja i sirup nakon dva tjedna.

Abstract (english)

Purpose of this work was determination of physicochemical composition (dry matter, pH value, total acidity and color parameters) and biologically active compounds in sour cherry marasca (Prunus cerasus var.marasca) during preparation of sour cherry syrup. There is a traditional way for home made preparation of sour cherry syrup.Sour cherry marasca samples were treated by adding sugar and keeping on the sun in closed jar, for one month. While sugar was melting, juice flew out of fruit, and the product is sour cherry syrup and partially dehydrated sour cherry fruit. Five samples were analized: fresh sour cherry as control sample, sour cherry fruit and juice after two weeks, sour cherry fruit and juice after four weeks. Dry matter is measured by digital refractometar, pH value by pH-meter, and total acidity by titration with NaOH solution. Total phenols and flavonoids were determined by spectrophotometric method, total anthocyanins by pH –differential method, and antioxidant capacity by DPPH method. According to the obtained results, adding sugar and keeping the samples on the sun, results with increasing of content of biologically active compounds in sour cherry marasca, althought the highest values are significant for the control sample. The sour cherry fruit and the juice after two weeks have the highest dry matter values.

• Keywords: višnja maraska; biološki aktivni sastojci; antocijani; ukupna boja; stajanje na suncu; dodatak šećera
• Keywords (english): sour cherry marasca; biologically active compounds; anthocyanins; keeping on the sun; adding sugar
• Language: croatian
• URN:NBN: urn:nbn:hr:159:871627
• 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: Access restricted to students and staff of home institution
• Created on: 2017-05-03 11:50:10