In our study we compared the impact of five different coffee preparation methods on the extraction of bioactive compounds, which give the beverage its characteristic color, aroma and flavor. We prepared coffee extracts from ground coffee beans using the following methods: espresso, drip coffee maker, Turkish coffee, moka pot and french press. We milled the coffe beans to appropriate grind size for each method and followed the typical preparation procedure for each type of coffee extraction. Using HPLC analysis we analyzed numerous phenolic compounds and alkaloids in coffee extracts. The duration of extraction and the water temperature varied depending on the selected preparation method which influenced the concentration of compounds in the extract.The results showed that the highest content of compounds extracted from the ground coffee was obtained with the Turkish preparation method while the lowest content was obtained with the filter coffee machine. The second part of the experiment was to determine the effect of water temperature and extraction time on the extraction of the substances. We used the french press method, heated the water to 80 °C, 90 °C, and 100 °C and extracted the ground coffee for 4, 8, 12, and 16 min. The results showed no significant differences in metabolite content between the different water temperatures and extraction times. Hydroxycinnamic acids represented the largest share of all extracted compounds in the coffee extract, while caffeine was the most abundant among the alkaloids.
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