Antioxidative capacity of birch saps

Abstract

In our subsequent studies of birch tree saps we focused on assessing their antioxidant capacity. For research we chose four groups of silver birch trees (Betula pendula Roth.), consisting of five individuals. Antioxidant capacity was examined using spectrophotometric technique. The highest antioxidant capacity, tested by the Folin-Ciocalteau method and expressed as a total phenolics content was 6.59 mg GAE/100 ml of tree sap, and in turn the lowest one 0.88 mg GAE/100 ml. The highest antioxidant capacity determined ABTS method and expressed as radical scavenging activity (RSA) was 30.9% and lowest 5.38% The average values of antioxidant capacity both expressed as a phenolic compounds content and as radical scavenging activity for tree saps collected from four particular locations did not differ significantly. Based on the obtained results of tree sap analyses, it can be claimed that compared to other food products, e.g. fruit and vegetable juices, birch saps are not a rich source of phenolic compounds and when compared e.g. to tee infusions, they have low antioxidant capacity. Although it can be increased by the introduction of functional additives, such as herbal extracts or concentrated fruit juices.