Antioksidacijska i senzorska svojstva čokolada sa zamjenskim sladilima

undergraduate thesis

• Title (english): Antioxidant and sensory properties of chocolate with substitute sweeteners
• Author: Petra Poldan
• 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: 2020-09-01, Croatia
• Scientific / art field, discipline and subdiscipline: BIOTECHNICAL SCIENCES; Food Technology

Abstract

Zdravstveni problemi uzrokovani nepravilnom prehranom, uključujući prekomjernu konzumaciju šećera, rezultirali su povećanom potražnjom proizvoda u kojima je saharoza zamijenjena „zdravijim“ sladilima. Cilj ovog rada je određivanje udjela ukupnih polifenola i pojedinih polifenolnih skupina, antioksidacijskog kapaciteta i senzorskih svojstava 10 čokolada od kojih 5 ima 69,69% kakaovih dijelova, a preostalih 5 ima 79,69% kakaovih dijelova, proizvedenih s različitim sladilima. Navedene čokolade proizvedene su uz: saharozu, kokosov šećer, agavin sirup, rižin slad i ječmeni slad. Udio ukupnih polifenola i neflavonoida određivan je kolorimetrijskom reakcijom s Folin-Ciocaltea-u reagensom, udio flavan-3-ola određen je metodama s vanilinom i p-DAC reagensom, dok je udio proantocijanidina određen metodom po Bate-Smith-u. Antioksidacijski kapacitet određen je ABTS i DPPH metodama, a senzorska svojstva određena su primjenom kvantitativne deskriptivne analize. Čokolade s višim udjelom kakaovih dijelova bogatije su bioaktivnim sastojcima pa tako čokoladu sa 79,69% kakaovih dijelova uz dodatak kokosovog šećera karakterizira najveći udio ukupnih polifenola (17,244 mg EGK/g uzorka), dok čokolada sa 79,69% kakaovih dijelova uz dodatak saharoze ima najveći antioksidacijski kapacitet (0,102 mmol Trolox/g uzorka). Čokolada sa 69,69% kakaovih dijelova uz dodatak ječmenog slada bila je senzorski općenito najbolje prihvaćena.

Abstract (english)

Health issues caused by improper diet, including over consumption of sugar, resulted in increased demand of products in which saccharose is replaced with “healthier” sweeteners. Goal of this research is to determine total amount of polyphenols, flavonoids and non-flavonoids, proanthocyanins, flavan-3-ol, antioxidant capacity and sensor analysis of 10 kinds of chocolate of which 5 have 69,69% cacao content, other 5 samples have 79,69 cacao content, produced with different sweeteners. Samples contained these sweeteners: saccharose, coconut sugar, agave syrup, rice malt and barley malt. Total amount of polyphenols and non-flavonoids was determined by colorimetric reaction with Folin-Cicolateu regent, flavan-3-ols were determined with vanillin method and p-DAC method and proanthocyanidins were determined with Bate-Smith method. Antioxidant capacity was determined by ABTS and DPPH method, sensory properties were determined by applying quantitative descriptive analysis. Chocolates with greater cacao content are richer in bioactive compound, so chocolate with 79.69% cacao content with addition of coconut sugar is characterized by greatest amount of polyphenols(17,244 mg EGK/g), while chocolate with 79.69% coco content with addition of saccharose has greatest antioxidation capacity (0,102 mmol Trolox/g of 1 sample) chocolate with 69.69% of cacao content with addition of barley malt was sensory rated as generally best accepted.

• Keywords: antioksidacijska aktivnost; čokolada; polifenoli; senzorska analiza; sladila
• Keywords (english): antioxidant activity; chocolate; polyphenols; sensory analysis; sweeteners
• Language: croatian
• URN:NBN: urn:nbn:hr:159:488442
• 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: Open access
• Created on: 2020-11-03 14:13:56