Malt is the main raw material for beer production, which determines not only its taste and aroma profile, but to a large extent its biological value, as well. The aim of the present research was to determine the antioxidant profile of different malt types as a basis for the development of new types of beer with increased antioxidant activity. In the present study the main brewing characteristics, the phenolic profile and the antioxidant potential of 20 malt types used in craft breweries in Bulgaria have been examined. The main brewing characteristics have been determined by the standardized methods of the European Brewing Convention. Malt phenolic content was determined by two methods, and antioxidant potential by five different methods. Based on a statistical factor analysis performed by the principal component analysis, it was confirmed that there was a relationship between malt color and phenolic compounds content. The principal component analysis confirmed that there was a link between the content of the Maillard reaction products and malt biological activity. Malts with the highest degree of heat treatment were characterized by the highest antioxidant activity, which was due to the content of Maillard reaction products with antioxidant capacity.
Keywords: 2,2′-azinobis-(3-ethylbenzothiazoline-6-sulfonate (ABTS); 2,2′-diphenyl-1-picrylhydrazyl (DPPH); Oxygen Radical Absorbance Capacity (ORAC); antioxidant capacity; cupric reducing antioxidant capacity (CUPRAC); ferric reducing ability of plasma (FRAP); malt; phenolic compounds; principal component analysis.