Biological activity, antioxidant capacity and volatile profile of enriched Slovak chocolates

Abstract

Different kinds and types of chocolates produced in Slovakia with various fruit and nut enrichments were analysed regarding total polyphenols, flavonoids and phenolic acids contents using spectrophotometric methods and their volatile profile was analysed using gas chromatography–mass spectrometry. The method with 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2’-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) and ferric reducing power method (FRAP) were used to measure antioxidant activity. Plain dark chocolate without any enrichment made by a traditional process contained the highest number of total polyphenols and phenolic acids and also had the highest antioxidant activity. Positive correlation was observed between antioxidant activity and total contents of phenolic compounds, flavonoids and phenolic acids. The enrichment with different kinds of fruits did not increase the number of bioactive compounds or antioxidant capacity of chocolates but created more attractive sensory profiles due to the presence of new volatile compounds.