Effect of Cocoa Shell Addition on Content and Composition of Chocolate Bioactive Components

Čokolada je jedna od najpoznatijih svjetskih slastica stoga je često predmet istraživanja. U novije vrijeme fokus istraživanja jest poboljšanje nutritivnih svojstva čokolade. Kakaova ljuska sadrži fenolne tvari, metilksantine, prehrambena vlakna i vitamin D te je pogodan dodatak u proizvodnji funkcionalnih čokolada. Zadatak ovog rada je ispitati utjecaj dodatka različitih udjela kakaove ljuske na sastav i udio polifenola i metilksantina u različitim vrstama čokolade. Sastav i udio polifenola (galne kiseline, kava kiseline, p-kumarinske kiseline, (+)-katehina, (-)-epikatehina, (-)-epikatehin galata) i metilksantina (teobromina i kofeina) određen je HPLC metodom, a udio ukupnih fenola Folin-Ciocalteu metodom. U čokoladama gdje je dodana kakaova ljuska bio je manji udio bioaktivnih komponenti, uz izuzetak udjela (-)-epikatehin galata. Uzorci s netretiranom kakaovom ljuskom u usporedbi s uzorcima koji sadrže tretiranu kakaovu ljusku imali su veće koncentracije pojedinačnih fenola i metilksantina određenih HPLC metodom te ukupnih fenola određenih spektrofotometrijskom metodom. Zamjena dijela kakaove mase kakaovom ljuskom nije značajno smanjila udio bioaktivnih komponeneti što otvara mogućnost proizvodnje funkcionalnih čokolada sa dodatkom kakaove ljuske.Chocolate is one of the world's most famous desserts so it is often the subject of research. More recently, the focus of research has been on improving the nutritional properties of chocolate. Cocoa shell contains phenolic substances, methylxanthines, dietary fiber and vitamin D and is a suitable additive in the production of functional chocolates. The aim of this study is to examine the effect of the addition of different share of cocoa shell on the composition and content of polyphenols and methylxanthines in different types of chocolate. The composition and content of polyphenols (gallic acid, caffeic acid, p-coumaric acid, (+)-catechin, (-)-epicatechin, (-)-epicatechin gallate) and methylxanthines (theobromine and caffeine) were determined by HPLC method, and the total phenolic content by Folin-Ciocalteu method. In chocolates where cocoa shell was added, there was a lower content of bioactive components, with the exception of (-)-epicatechin gallate. Samples with untreated cocoa shell had higher concentrations of individual phenols and methylxanthines determined by HPLC method and total phenols determined by spectrophotometric method compared to samples containing treated cocoa shell. Replacing part of the cocoa mass with cocoa shell did not significantly reduce the share of bioactive components, which opens the possibility of producing functional chocolates with the addition of cocoa shell