Antioksidacijska svojstva čokolada obogaćenih probioticima

undergraduate thesis

• Title (english): Antioxidant properties of chocolate enriched with probiotic
• Author: Mirna Dora
• Mentor: Draženka Komes (mentor)
• Granter: University of Zagreb; Faculty of Food Technology and Biotechnology; (Department of Food Engineering); (Laboratory for Chemistry and Technology of Carbohydrates and Confectionery Products); Zagreb
• Defense date and country: 2011-07-22, Croatia
• Scientific / art field, discipline and subdiscipline: BIOTECHNICAL SCIENCES; Nutrition

Abstract

Posljednjih je godina zanimanje znanstvenika posebno usmjereno prema prirodnim antioksidansima i njihovoj ulozi u zaštiti ljudskog zdravlja. Čokolada je prema mnogim istraživanjima bogata antioksidansima i to polifenolima [(-)epikatehin, (+)- katehin i procijanidini]. Osim toga, sve je veća potražnja za čokoladama obogaćenim začinima, ljekovitim biljem, eteričnim uljima, probioticima i drugim sastojcima koji doprinose njihovom poboljšanom nutritivnom sastavu i antioksidacijskom kapacitetu. Cilj ovog rada bio je odrediti udio ukupnih fenola i flavonoida te antioksidacijski kapacitet tri vrste čokolada različitiog udjela kakaovih dijelova (30%, 40%, 70%) koje su obogaćene različitim probiotičkim kulturama Lactobacillus sp. Udjel ukupnih fenola i flavonoida određen je reakcijom s Folin-Ciocalteu reagensom. Antioksidacijski kapacitet određen je reakcijama sa željezo(III)-tripiridiltriazina (FRAP) te pomoću radikala 2,2'-azinobis (3–etilbenzotiazolin-6-sulfonske kiseline) (ABTS). Najveći udio ukupnih fenola određen je u tamnoj čokoladi (70% suhe tvari kakaovih dijelova), dok su najniži udjeli istih određeni u mliječnoj čokoladi (30% suhe tvari kakovih dijelova). Antioksidacijski kapacitet povećavao se proporcionalno porastu suhe tvari kakaovih dijelova. Utjecaj dodatka probiotičkog soja nije značajno utjecao na antioksidacijska svojstva čokolada.

Abstract (english)

During last few years, natural antioxidants and their role in human health are matters of great interest among scientists. According scientific studies, chocolate is a rich source of natural antioxidants, mainly polyphenols [(-)epicatechin, (+)- catechin and procyanidin]. Besides that, market demand for chocolates enriched with condiments, herbs, essential oils, probiotics and other ingredients, which give benefit to the better nutrient status and antioxidant capacity, is increasing. The aim of this study was to examine the content of total phenols and flavonoids and to determine antioxidative capacity of three different kinds of chocolate cocoa solids (30%, 40%, 70%) and were enriched with probiotic cultures Lactobacillus sp. The concentration of total phenols and flavonoids was determined by using a reaction with Folin-Ciocalteu reagent while the antioxidative capacity was determined by using reactions with iron(III)-tripyridyilitrazine (FRAP) and radicals 2,2'-azinobis (3–ethylbenzothiazoline-6-sulfonic acid) (ABTS). The highest content of total phenols was determined in dark chocolate (70% of dry matter cocoa products) while the lowest content was detected in milk chocolate (30% of dry matter cocoa products). Antioxidant capacity is increased proportionately with the increase of dry matter cocoa products. Effect of probiotic strains did not significantly affect the antioxidant properties of chocolate.

• Keywords: čokolada; probiotici; antioksidacijska aktivnost; polifenoli
• Keywords (english): Chocolate; probiotics; antioxidant activity; polyphenols
• Language: croatian
• URN:NBN: urn:nbn:hr:159:205452
• Study programme: Title: Nutrition; Study programme type: university; Study level: undergraduate; Academic / professional title: sveučilišni/a prvostupnik/prvostupnica (baccalaureus/baccalaurea) nutricionizma (sveučilišni/a prvostupnik/prvostupnica (baccalaureus/baccalaurea) nutricionizma)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Access restricted to students and staff of home institution
• Created on: 2017-05-18 11:19:53