Elderberry (Sambucus nigra L.) Beer with Antioxidant Properties

Fruits and berries increase the antioxidant activity of beer. Elderberries (Sambucus nigra L.) contain biologically active compounds with high antioxidant capacity. The research objective was to develop a new kind of beer with elderberries introduced at different stages of the technological process, as well as to study the antioxidant activity of this functional drink. The pH was determined with a pH meter, the carbohydrate content and color – with a spectrophotometer, the optical density – with a spectrophotometer, the total polyphenol content – by the Folin-Ciocalteu colorimetric method, the antioxidant activity – by the DPPH radical scavenging method, and the absorption – with a UV-visible spectrophotometer at λ = 517 nm. Elderberries added in the amount of 62.5 and 125 g/dm3 increased the degree of fermentation. According to the European Brewing Convention, the optimal beer color is 22.29 units. To achieve this standard, elderberries had to be added 15 min after the start of boiling the wort. When elderberries were added to the cooled wort, its color decreased by 6.97 units. The concentration of elderberries appeared to have a positive correlation with the antioxidant activity of the finished product: more elderberries meant more polyphenols. The pH did not change during the brewing process and remained within the standard limit of 4.25–4.81. When the concentration of elderberries was 1.25 g/dm3, the antioxidant activity increased by 13.4 times, at 125 g/dm3 – by 22 times. The beer reached its maximal antioxidant activity when elderberries were added to uncooled wort after boiling; it decreased by 16.1% when elderberries were added after cooling the wort. The content of polyphenols in elderberry beer depended on the concentration of elderberries, while the color and antioxidant capacity – on the amount of elderberries and the stage of the technological process. Unfiltered and unpasteurized elderberries maximized the antioxidant activity and nutritional value of the finished product. The new beer sort will allow microbreweries to expand their product range and attract new consumers.