Within the diploma thesis we compared the content of total phenolic compounds (SFS) and antioxidant activity (AOU) in coffee from South America (Guatemala, Brazil, Rio Verde - Brazil) and Barcaffe coffee, which is widely consumed in Slovenia. Coffee was prepared as espresso and as filter. We also prepared them with two volumes of water and with addition of milk. The content of SFS was determined by the Folin-Ciocalte method and expressed as chlorogenic acid equivalent. The AOU was detected by the free DPPH • radical and expressed as trolox equivalent. The results show that the preparation method, the amount of water and the addition of milk affect the content of SFS and AOU in coffee. The average SFS content in espresso coffee is 20,5 mM and in filter coffee 7,4 mM, the average AOU in espresso coffee is 20,0 mM and 16,1 mM in filter coffee. The differences are obvious because the filter coffee contains less SFS and has a lower AOU than espresso coffee. By using a larger amount of water, the total content of SFS and AOU increases with both methods of coffee preparation. Milk affects by slightly increased SFS content and reduced AOU. Our results also show that the origin of coffee has no significant influence on the content of SFS and AOU, more important is the process of its preparation.
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